Dissertations / Theses: 'Biopesticides'

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Paoli, Pier Paolo. "Novel sources of biopesticides." Thesis, University of Newcastle Upon Tyne, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.555978.

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In recent years changing agricultural conditions are leading to insect pests becoming a more serious threat to UK crop production for a variety of local and global factors. Two important factors in these changes are: (i) increasing public intolerance of the use of exogenously applied chemical insecticides which can have negative effects both in terms of public health (through exposure to residues on food crops) and the environment; and (ii) changes in the distribution and abundance of insect pests as a result of increased mean temperatures resulting from global climate change, which will alter the pest breeding habits and periods of damage. In terms of environmental effects, are the effects on non-target organisms including beneficial insects that play a role in the suppression of insect pest populations. To control pests, the development of novel pesticides should focus on non-chemical alternatives derived from natural sources. In the present study venom proteins were isolated and purified from the parasitoid wasp Eulophus pennicornis (Hymenoptera: Eulophidae) and the sea anemone Actinia equina (Actiniaria: Actiniidae) by gel filtration on a 16/60 HR Sephacryl and anion exchange FPLC chromatography (Pharmacia-LKB Mono Q HR 5/5) in order to evaluate their potential toxicity towards lepidopteran (Lacanobia oleracea) and dipteran (Musca domestica) larvae. Characterisation of the parasitoid venom by DNA sequencing of a venom gland cDNA library demonstrated the presence of trypsin-like serine proteases (NM_001170877), insulin-like growth factors (NP _001082137), late trypsin (XP _001604401), and metalloproteases (XP _001599927.1). Venom proteins from the sea anemone were identified by mass spectrometry (MALDI TOF/TOF) as actinoporins (Q9Y1U9) and Na+ and K+ channel inhibitors which are known to act as neurotoxins (P61541, Q9NDA5, P81791). Genes encoding purified parasitoid proteins were subsequently expressed in Pichia pastoris as a microbial expression system and the late trypsin recombinant protein was tested for insecticidal activity. Sea anemone toxins, on the other hand, were purified from source for subsequent bioassay. The recombinant proteins and protein fractions were then tested for their insecticidal activity by injection into L. oleracea and M domestica larvae. Anti-moulting factor and juvenile hormone esterase inhibition factor purified from the parasitoid venom were shown to cause between 70-100% and 50-90% mortality respectively in L. oleracea after a period of 14 days, with observable physiological changes beginning on day 7; the recombinant late trypsin protein (XP _ 001604401) was shown to cause 70% mortality in L. oleracea larvae after 8 days. Out of 30 fractions isolated from sea anemone acrorhagi using gel.

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Thiec, Marie Alliot Anne. "La lutte biologique et les biopesticides." [S.l.] : [s.n.], 2007. http://castore.univ-nantes.fr/castore/GetOAIRef?idDoc=22986.

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Rodríguez, Serrano Paula. "Valorización de digestato como sustrato para la producción de biopesticidas con Bacillus thuringiensis mediante fermentación en estado sólido." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/669776.

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Aquesta tesi és part del projecte DECISIVE, finançat pel programa europeu H2020 (acord de subvenció N° 689.229), que té com a objectiu proposar i provar un esquema de gestió descentralitzada per a la valorització dels residus sòlids orgànics municipals. L'objectiu general d'aquesta investigació és la producció de bioproductes de valor afegit a partir del digestat de fracció orgànica de residus sòlids municipals com a substrat mitjançant l'ús de la fermentació en estat sòlid (FES). El principal bioproducte a explorar és un biopesticida inoculant el digestat amb Bacillus thuringiensis (Bt), conegut per les seves propietats biopesticides. En primer lloc, es van realitzar proves a escala laboratori per comprovar la idoneïtat del digestat per a l'obtenció de diferents bioproductes (cel·lulases, soforolípids, proteases i biopesticides), aconseguint els millors resultats de producció per al biopesticida produït per Bt. Aquests experiments es van realitzar amb digestat estèril i digestat higienitzat, observant que aquest microorganisme era capaç de créixer i esporular utilitzant digestat higienitzat. Posteriorment, es van estudiar un seguit d'estratègies d’operació en reactors aïllats tèrmicament de 10-L amb digestat higienitzat. El procés es va escalar a un reactor de 100-L de llit empacat sense aïllament i amb agitació, observant una esporulació del 89% amb un creixement d'espores 3 vegades més gran que l'inicial, mostrant produccions de biopesticida a partir de Bt. Posteriorment, es va realitzar una comparació entre dues soques de Bt, Bacillus thuringiensis subespècie kurstaki (Btk) i Bacillus thuringiensis subespècie israelensis (Bti). Es va avaluar la diferència de les dues soques a escala laboratori 0.5-L observant els efectes d'esterilització, la higienització i la congelació del digestat en la producció de cèl·lules viables i espores per Btk i Bti. Paral·lelament, es van realitzar proves de conservació, anàlisi microbiològic i bioassaigs del digestat. Amb tots els resultats anteriors, els últims anàlisis realitzats en aquesta tesi van ser l'optimització de l'extracció i caracterització de la toxina produïda per Bt a partir del cristall proteic, concentrat i conservat a través de tècniques com: la disrupció, on es van disminuir les cèl·lules viables i es va incrementar la producció d'espores, desprenent el cristall proteic i la liofilització per conservar el material, on es va observar un 86 i 89% de recuperació de les espores per Btk i Bti. Es va realitzar una purificació del substrat, determinant les proteïnes característiques de Bt amb efecte biopesticida a partir d'una electroforesi. Aquesta tesi és un pas endavant per comprovar les característiques del cristall proteic de Bt amb efecte biopesticida a partir de FES i poder utilitzar el producte final valoritzant així el residu del tractament de la fracció orgànica de residus municipals.
Esta tesis es parte del proyecto DECISIVE, financiado por el programa europeo H2020 (acuerdo de subvención N ° 689229), que tiene como objetivo proponer y probar un esquema de gestión descentralizada para la valorización de los residuos sólidos orgánicos urbanos. El objetivo general de esta investigación es la producción de bioproductos de valor añadido a partir del digestato de fracción orgánica de residuos sólidos municipales como sustrato mediante el uso de la Fermentación en Estado Sólido (FES). El principal producto a explorar es un biopesticida a obtener inoculando el residuo con Bacillus thuringiensis (Bt), que produce un cristal proteico con propiedades biopesticidas. En primer lugar, se realizaron pruebas a escala laboratorio para comprobar la idoneidad del digestato para la obtención de diferentes bioproductos (celulasas, soforolípidos, proteasas y biopesticidas), alcanzando los mejores resultados de producción para el biopesticida producido por Bt. Posteriormente, se probaron una serie de estrategias de producción en reactores aislados térmicamente de 10-L con digestato higienizado pasando a escalar el proceso a un reactor de 100-L de lecho empacado sin aislamiento y con agitación observando una esporulación del 89% con un crecimiento de esporas 3 veces mayor que el inicial. Posteriormente, se realizó una comparación entre dos cepas de Bt, Bacillus thuringiensis subespecie kurstaki (Btk) y Bacillus thuringiensis subespecie israelensis (Bti). Se evaluó la diferencia en el crecimiento y esporulación de ambas cepas a escala laboratorio (0.5-L) observando los efectos de la esterilización, la higienización y la congelación del digestato en la producción de células viables y esporas por Btk y Bti. Después de evaluar los efectos a escala laboratorio y en relación con los experimentos realizados con reactores aislados de 10-L, se estudia el crecimiento de ambas cepas en estos reactores con 1.5 kg de residuo para evitar los incrementos de temperatura, comparándolos con dos tipos de sustrato: digestato y digestato con fracción orgánica de residuos municipales (FORM) (50:50). Paralelamente, se realizaron pruebas de conservación, análisis microbiológico y bioensayos del bioproducto. Con todos los resultados anteriores, las últimas pruebas realizadas en esta tesis fueron la optimización de la extracción y caracterización de la toxina producida por Bt a partir del cristal proteico, concentrado y conservado a partir de técnicas como: la disrupción, y la liofilización, para conservar el material, donde se observó un 86 y 89% de recuperación de las esporas para Btk y Bti. Se realizó también una purificación del sustrato, para la determinación de las proteínas con efecto biopesticida caracteristicas de Bt a partir de una electroforesis. Esta tesis es un paso adelante para comprobar las posibilidades de obtención del cristal proteico de Bt con efecto biopesticida a partir de FES y poder utilizarlo valorizando los residuos del tratamiento de la fracción orgánica de residuos municipales.
This thesis is part of the DECISIVE project, funded by the European program H2020 (grant agreement No. 689229), which aims to propose and test a decentralized management scheme for the recovery of municipal organic waste. The general objective of this research is the production of value-added bioproducts using digestate of the organic fraction of municipal solid waste as a substrate through solid-state fermentation (SSF). The main bioproduct to explore is a biopesticide inoculating the digestate with Bacillus thuringiensis (Bt), which is known to produce a protein with biopesticidal properties. Firstly, laboratory scale tests were performed to verify the suitability of the digestate to obtain different bioproducts (cellulases, sophorolipids, proteases and biopesticides), achieving the best production results for the biopesticide produced by Bt. These experiments were performed with sterile digestate and hygienized digestate, observing that Bt was able to grow and sporulate using hygienized digestate. Subsequently, a series of operational strategies were studied in thermally insulated 10-L reactors using hygienized digestate. The same process was scaled to a 100-L stirred packed bed reactor without thermal insulation observing a sporulation of 89% with a spore growth 3 times greater than the initial value. Subsequently, a comparison was made between two strains of Bt, Bacillus thuringiensis subspecies kurstaki (Btk) and Bacillus thuringiensis subspecies israelensis (Bti). The difference among both strains at laboratory scale 0.5-L was evaluated observing the effects of sterilization, sanitation and freezing of digestate in the production of viable cells and spores by Btk and Bti. At the same time, conservation tests, microbiological analysis and digestate bioassays were performed. With all the previous results, the last analysis carried out in this thesis was the optimization of the extraction and characterization of the toxin produced by Bt from the protein crystal. Different techniques were applied to concentrate and preserve the protein crystal. The first one was a disruption where viable cells were decreased and spore production increased, releasing the protein crystal. The second one was a lyophilization to conserve the material, where 86 and 89% recovery of spores was observed for Btk and Bti. This thesis is a step forward to verify the characteristics of the Bt protein crystal with biopesticidal effect obtained through SSF and to be able to use the final product valorising the residues of the treatment of the organic fraction of municipal solid waste.

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Deravel, Jovana. "Caractérisation des lipopeptides d’origine non ribosomique comme biopesticides." Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10126.

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Le premier objectif de ce travail a été d’étudier l’implication des lipopeptides de Bacillus spp. dans la colonisation de la rhizosphère de tomates. Alors que seules les souches produisant de la surfactine sont capables de coloniser un milieu synthétique, toutes les souches testées, colonisent la rhizosphère de tomates avec une plus ou moins bonne efficacité quelque soit leur propriété de production de lipopeptide(s). L’efficacité de la colonisation des racines de tomates est principalement espèce-dépendante. Ce n’est que quand une souche est déjà une bonne colonisatrice que la surfactine semble améliorer cette propriété. Le deuxième objectif a été de tester l’effet des lipopeptides surfactine et mycosubtiline contre le phytopathogène obligatoire de la laitue : Bremia lactucae. À l’échelle du laboratoire, la mycosubtiline à 100 mg/L réduit le pourcentage de plantes infestées de 70 %. La surfactine ne montre aucun effet contre le champignon. Un mélange de mycosubtiline et de surfactine à 50 mg/L chacun diminue le pourcentage de plantes infestées de 65 %. Il semble diminuer le nombre de spores par plante infestée alors que cette propriété n’est pas remarquée avec les autres traitements. L’utilisation de la mycosubtiline dans une serre de culture limite la maladie aux symptômes les moins sévères et protège les plantes saines d’une contamination croisée. L’action des lipopeptides dans la colonisation des racines par Bacillus spp. n’avait jamais été validée in situ. De même, c’est la première fois que l’activité des lipopeptides est testée contre un phytopathogène obligatoire
The first aim of this work was to study the role played by the lipopeptides of Bacillus spp. in the colonization of the tomato rhizosphere. While only the strains producing surfactin are able to colonize a synthetic agar medium, all the strains are able to colonize the rhizosphere of tomatoes with a more or less good efficiency, whatever the lipopeptide(s) they have the capability to produce. The efficiency of the colonization of the tomato rhizosphere is species-dependant. However, surfactine seems to improve the efficiency of only the good colonizing strains. The second aim of this thesis was to test the effect of surfactin and mycosubtilin against a biotrophic parasite of lettuce: Bremia lactucae. Used at 100 mg/L, mycosubtilin reduces the percentage of infested plants of 70 %. Surfactin does not have effect against the fungy. A mixture of mycosubtilin and surfactin at both 50 mg/L decreases the percentage of infested plants of 65 %. This mixture seems to reduce the number of spore per infested plant while this property was not found for the other treatments. The use of mycosubtilin in a greenhouse confines the disease to the lowest classes of severity and protects the healthy plants from a cross contamination.The efficiency of lipopeptides of Bacillus spp. in root colonization by these bacteria was never tested in situ before. Furthermore, this is the first time that the activity of lipopeptides is validated against an obligate phytopathogen

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Lintz, Julie. "Caractérisation fonctionnelle et valorisation de peptides de défense multifonctionnels chez les arbres de la famille des Salicacées." Electronic Thesis or Diss., Université de Lorraine, 2023. http://www.theses.fr/2023LORR0151.

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Les plantes possèdent un système immunitaire capable de stopper la progression des agents pathogènes et de prévenir l'apparition des maladies. Ce système immunitaire utilise des peptides de défense pouvant avoir deux fonctions distinctes: antimicrobiennes ou élicitrices. Rust Induced Secreted Peptide from Populus trichocarpa (PtRISP1) est un peptide du peuplier qui présente à la fois une activité antimicrobienne envers les champignons de l'ordre des Pucciniales et une activité élicitrice des réponses immunitaires chez le peuplier. Les objectifs de la thèse étaient de caractériser le mode d'action antifongique et éliciteur de PtRISP1 et de ses homologues et d'entreprendre des démarches de valorisation de ces peptides comme composés anti-pucciniales. Cette thèse comporte cinq chapitres : un chapitre d'introduction, trois chapitres de résultats, et un chapitre de discussion. Le Chapitre I présente une synthèse bibliographique portant sur l'immunité des plantes, les peptides de défense, les Salicacées, les Pucciniales, et le peptide PtRISP1. Le Chapitre II présente des résultats concernant l'activité élicitrice des peptides RISP. Il montre notamment qu'au sein des génomes des peupliers et des saules, les gènes RISP sont systématiquement regroupés avec des gènes codant pour des récepteurs membranaires de type Leucine Rich Repeat Receptor Proteins (LRR-RP), que nous avons appelés RISP-Associated LRR-RPs (RALR), et que les RALR reconnaissent les peptides RISP pour induire la signalisation immunitaire. Le Chapitre III présente des résultats concernant l'activité antimicrobienne de PtRISP1. Il montre notamment que PtRISP1 cible les extrémités apicales des urédospores de Melampsora larici-populina via des régions protéiques chargées, a une activité spécifique envers les Pucciniales, et s'attache à la surface des feuilles. Le Chapitre IV présente une analyse préliminaire de la famille RISP, qui montre que des membres divergents de la famille présentent des activités anti-Pucciniales et des propriétés biophysiques similaires à PtRISP1. Enfin, le Chapitre V discute les résultats de la thèse en les replaçant dans un contexte plus large et met en perspective la valorisation des peptides végétaux en agriculture. Pour conclure, ces travaux de thèse ont mis en évidence que les peptides RISP sont des phytocytokines reconnues par des récepteurs immunitaires spécifiques, possèdent une activité antimicrobienne spécifique envers les Pucciniales, et ont évolué conjointement avec leurs récepteurs chez les arbres de la famille des Salicacées
Plants have an immune system able to stop the progress of pathogens and prevent the development of disease. This immune system uses defense peptides that can have two distinct functions: antimicrobial or elicitor. Rust Induced Secreted Peptide from Populus trichocarpa (PtRISP1) is a peptide from poplar that exhibits both antimicrobial activity against fungi of the order Pucciniales and elicitor activity in poplar. The objectives of the thesis were to characterize the antifungal and elicitor mode of action of PtRISP1 and its homologues, and to initiate steps to valorize these peptides as anti-pucciniales compounds. This thesis comprises five chapters: an introduction, three results chapters and a discussion chapter. The Chapter I presents a synthesis of the literature on plant immunity, defense peptides, Salicaceae, Pucciniales and the PtRISP1 peptide. Chapter II presents results concerning the elicitor activity of RISP peptides. In particular, it shows that within the poplar and willow genomes, RISP genes are systematically clustered with genes encoding Leucine Rich Repeat Receptor Proteins (LRR-RP), which we have called RISP-Associated LRR-RPs (RALRs), and that RALRs recognize RISP peptides to induce immune signaling. The Chapter III presents the results concerning the antimicrobial activity of PtRISP1. In particular, it shows that PtRISP1 targets the apical tips of Melampsora larici-populina urediniospores via charged protein regions, has specific activity towards Pucciniales, and attaches to leaf surfaces. The Chapter IV presents a preliminary analysis of the RISP family, showing that divergent family members exhibit anti-Pucciniales activities and biophysical properties similar to PtRISP1. Finally, the Chapter V discusses the results of the thesis, placing them in a more wider context and putting the valorization of plant peptides in agriculture into perspective. In conclusion, this thesis work has demonstrated that RISP peptides are phytocytokines recognized by specific immune receptors, have a specific antimicrobial activity towards Pucciniales, and have co-evolved with their receptors in trees of the Salicaceae family

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Ozcan, Orhan. "Medium Development For Production Of Bacillus Thuringiensis Based Biopesticides." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609285/index.pdf.

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The insect pathogen Bacillus thuringiensis (Bt) holds great promise as an effective and friendly way for management of the pests with safety for nontarget animals and humans. However, high capital investment due to high production and formulation cost of commercial Bt preparations has caused prohibitive effect on companies. The present study mainly aimed at developing a low cost medium that supports the growth of different Bt strains and their specific bioinsecticidal &
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-endotoxins (crystal proteins). A comparison was made between the representative members of three different subspecies of Bt to observe toxin yields in response to certain nutritional conditions. Three different Bt subspecies were Bt kurstaki (strain 81), Bt israelensis (strain HD500) and Bt tenebrionis (strain 3203), producing lepidoptera- and diptera-specific Cry1 and Cry2, diptera-specific Cry4Ba and Cry11Aa and coleoptera-specific Cry3Aa toxins, respectively. Studies were conducted to optimize glucose and inorganic phosphate concentrations in standard DSM medium for the production of these Bt-based biopesticides. General suppression of toxin yields in high glucose medium (10 g/L) thought the generality of carbon catabolite regulation for biosynthesis of different types of toxins. Inorganic phosphate (Pi) level was important for Cry4Ba, Cry11Aa and Cry3Aa biosynthesis while Cry1 and Cry2 production was not responsive to high Pi. Wastewater sludge, fruit residues and broiler litter were next tested as cheap raw materials for Bt-based biopesticide production in batch cultures. Broiler litter seemed to be a much better substrate among all since some degree of production of each toxin was observed at almost every stage of fermentation. The processing of broiler litter was found to significantly improve toxin yields. The medium prepared from processed broiler litter was successfully used to cultivate all Bt stains and obtain bioinsecticidal proteins in high yields which were comparable or higher than those that can be obtained on standard semi-synthetic media.

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Wilson, Jonathan Alexander. "Novel downstream processing for recovery of nematodes for biopesticides." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404895.

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Besset-Manzoni, Yoann. "Améliorer les principes de sélection de nouveaux agents bactériens de biocontrôle contre la fusariose du blé." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1124/document.

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Pour lutter contre les nuisibles des cultures (herbivores et pathogènes), de nouvelles voies ont été explorées et en particulier la lutte biologique. Utilisé la nature et ses organismes pour réguler les populations de pathogènes, tel est le but de la lutte biologique aussi appelé biocontrôle. Parmi les organismes couramment retrouvés dans le biocontrôle se trouve les micro-organismes, que cela soit des champignons ou des bactéries. Ces micro-organismes possèdent des capacités très intéressante pour des agriculteurs et agronomes. En effet, des études ont montré qu’ils étaient capables d’interagir avec les plantes pour permettre une meilleure croissance et santé de celle-ci. Alors, dans cette thèse, nous nous sommes intéressés aux bactéries pour trouver des méthodes de luttes alternatives à Fusarium graminearum, un pathogène des céréales responsables de fortes pertes de rendements, en particulier grâce à la production de mycotoxines qui va rendre les grains impropres à la consommation humaine et animales. Par l’intermédiaire d’une approche original consistant à garder des souches non-inhibitrice in vitro pour des tests in planta, nous avons pu montrer les limites de la sélection in vitro. Grâce à l’exploration métaboliques d’une souche particulièrement efficace, nous avons aussi pu mettre en évidence de potentiels nouvelles molécules antifongiques. Par l’intermédiaire d’une souche modèle, nous avons explorer les mécanismes de la mise en place d’une résistance systémique chez le blé induite par les bactéries. Et enfin, nous avons exploré le potentiel des combinaisons de bactéries dans la protection du blé qui semble représenter un vrai futur dans le monde du biocontrôle. Les travaux effectués s’inscrivent dans les besoins de nouvelles ressources pour limiter l’utilisation des pesticides, mais aussi dans un besoin de mieux comprendre les interactions tripartite entre blé, pathogène et bactéries bénéfiques
To combat pests of crops (herbivores and pathogens) new pathways have been explored, in particular biological control. Used the nature and its organisms to regulate the populations of pathogens, that is the goal of the biological fight also called biocontrol. Among the organisms commonly found in biocontrol are micro-organisms, be they fungi or bacteria. These microorganisms have very interesting capabilities for farmers and agronomists. Indeed, studies have shown that they are able to interact with plants to allow a better growth and health of it.Then, in this thesis, we were interested in bacteria to find alternative methods of struggle with Fusarium graminearum, a pathogen of cereals responsible for high yield losses, especially thanks to the production of mycotoxins that will make the seeds unfit for human and animal consumption.Through an original approach of keeping noninhibitory strains in vitro for in planta tests, we have been able to show the limitations of in vitro selection. Thanks to the metabolic exploration of a particularly efficient strain, we have also been able to highlight potential new antifungal molecules. Through a model strain, we explored the mechanisms of the establishment of systemic resistance in wheat induced by bacteria. And finally, we have explored the potential of bacterial combinations in wheat protection that seems to represent a real future in the world of biocontrol.The work done is in line with the needs of new resources to limit the use of pesticides, but also in a need to better understand the tripartite interactions between wheat, pathogen and beneficial bacteria

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Mejias, Torrent Laura. "A step towards biowaste digestate valorization: process development for bt-derived biopesticides production through ssf and performace at demonstration scale." Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/671265.

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Dins el marc del projecte europeu DECISIVE (grant agreement No 689229) aquesta tesi es centra en la valorització del digestat obtingut de la gestió descentralitzada de la fracció orgànica dels residus municipals (FORM) mitjançant la tecnologia de fermentació en estat sòlid (FES). Treballs anteriors enfocats a la prova de concepte van destacar la viabilitat de produir biopesticides derivats de Bacillus thuringiensis (Bt) utilitzant digestat com a principal substrat. Partint d’;aquests resultats, es van realitzar una sèrie de dissenys d’;experiments a escala laboratori (0.5-L) per determinar els paràmetres amb més rellevància en la fermentació. La temperatura i l’;addició de FORM com a co-substrat es van identificar com a paràmetres clau del procés. Aquest efecte es va estudiar a una escala superior (1.6-L), confirmant la necessitat d’;afegir co-substrat per tal de millorar els rendiments de producció. En aquest punt, també es va identificar i destacar la importància dels nivells d’;oxigen durant les primeres hores de procés. Com a resultant, es va desenvolupar una estratègia d’;aeració per tal de maximitzar la producció d’;espores. Aquesta estratègia va ser validada a un reactor prototip (22-L), utilitzant dos soques diferents: Bt var. kurstaki i Bt var. israelensis. Els resultats van ser molt prometedors quan el procediment es realitzava en batch, però la producció final es veia reduïda significativament quan es treballava en fed-batch o batchs seqüencials. Finalment, aquesta estratègia de producció es va implementar al reactor pilot de 290-L, intentant aconseguir l’;ambient favorable per incrementar el creixement i esporulació de Bt. La qualitat del material fermentat va ser analitzada en termes de concentració d’;espores, maduresa del sòlid, i identificació i quantificació de microplàstics. Aquest projecte ha rebut finançament del programa de recerca i innovació Horizon 2020 de la Unió Europea segons el Grant Agreement No 689229.
Dentro del marco del proyecto europeo DECISIVE (grant agreement No 689229) esta tesis se centra en la valorización del digestato obtenido de la gestión descentralizada de la fracción orgánica de los residuos municipales (FORM) mediante la tecnología de fermentación en estado sólido (FES). Trabajos anteriores enfocados a la prueba de concepto destacaron la viabilidad de producir biopesticidas derivados de Bacillus thuringiensis (Bt) utilizando digestato como principal sustrato. A partir de estos resultados, se realizaron una serie de diseños de experimentos a escala laboratorio (0.5-L) con el objetivo de determinar los parámetros con más relevancia en la fermentación. La temperatura y la adición de FORM como co-sustrato se identificarion como parámetros clave del proceso. Su efecto se estudió a escala superior (1.6-L), confirmando la necesidad de añadir co-sustrato para mejorar los rendimientos de producción. En este punto, también se identificó y destacó la importancia de los niveles de oxígeno durante las primeras horas de proceso. Como resultado, se desarrolló una estrategia de aeración para maximizar la producción de esporas. Esta estrategia se validó en un reactor prototipo (22-L), utilizando dos cepas diferentes: Bt var. kurstaki y Bt var. israelensis. Los resultados fueron muy prometedores cuando el proceso operaba en bach, pero la producción final disminuía significativamente cuando se operaba en fed-batch o batch secuencial. Finalmente, esta estrategia de producción se implementó en el reactor piloto de 290-L, intentado lograr en ambiente favorable para incrementar el crecimiento y esporulación de Bt. Se estudió la calidad del sólido fermentado en referencia a la concentración de esporas, madurez del sólido, e identificación y cuantificación de microplásticos. Este proyecto ha recibido fondos del programa de investigación e innovación Horizon 2020 de la Unión Europea según el Grant Agreement No 689229.
In the framework of the European project DECISIVE (grant agreement No 689229) the present thesis is focused on the valorization of digestate from the decentralized management of the organic fraction of the municipal solid waste through the solid-state fermentation (SSF) technology. Previous work focused on the proof of concept of the idea highlighted the viability of producing Bacillus thuringiensis-derived biopesticides using digestate as a principal substrate. From these results, a first assessment at a laboratory scale (0.5-L) using the design of experiments’ methodology was performed for determining the more relevant parameters in the fermentation. Temperature and the use of biowaste as co-substrate were identified as key parameters for the process. This effect was studied at 1.6-L, confirming the need of adding co-substrate for increasing the production yields. At that point, the relevance of oxygen levels in the firsts hours of fermentation was identified and highlighted. As a result, an aeration strategy was developed with the aim of maximizing the spore production. This strategy was validated at a prototype reactor (22-L) using two different strains: Bt var. kurstaki and Bt var. israelensis. Promising results were observed when the process was performed on batch mode. However, the final production was significantly reduced when working on fed-batch or sequential batch mode. Lastly, the developed operation strategy was implemented at the 290-L pilot reactor, trying to achieve an adequate environment for boosting Bt growth and sporulation. The quality of the fermented material was assessed in terms of spore concentration, solid maturity, and microplastics identification and quantification. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 689229.

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Selim, Sameh. "Purification et caractérisation de la paenimyxine, un bio-pesticide produit par la bactérie tellurique, Paenibacillus sp. Souche B2 : étude de son impact sur des microorganismes du sol et les réactions de défense de la plante." Dijon, 2005. http://www.theses.fr/2005DIJOMU09.

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Dans ce travail, un facteur antagoniste produit par Paenibacillus sp. Souche B2 a été purifié. Ce facteur montre un large spectre d'action vis-à-vis de bactéries Gram- et Gram+, ainsi que des champignons pathogènes. Ce facteur est constitué de trois peptides antagonistes, nous avons proposé de les grouper sous le nom du "paenimyxine". Après un traitement du sol avec la paenimyxine, une réduction transitoire du nombre de bactéries cultivables, ainsi de leur structure génétique, a été observée entre 2 et 4 jours après le traitement. Après une incubation des racines de plantules de Medicago Truncatula avec 1,23uM de paenimyxine pendant 24 h, avant l'inoculation avec Fusarium acuminatum, 95% des symptômes nécrotiques sont supprimés. L'expression de 64 gènes connus pour être liés aux mécanismes de défense a été étudié par Northern inverse, et l'activation de l'expression des gènes a été confirmée par RT-PCR semi quantitative. La démonstration a été ainsi apportée pour la première fois que des molécules produites par une bactérie antagoniste, sont capables d'induire chez la plante une résistance vis-à-vis d'un champignon pathogène des racines.

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11

Li, Xiubin. "Synthesis of new dicinnamoyl quinic acid derivatives and analogs and the evaluation of their potential as biopesticides." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI032/document.

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L'utilisation de pesticides conventionnels, en particulier les pesticides chimiques de synthèse, a considérablement réduit les pertes de récoltes et a connu un succès commercial. Cependant, l'utilisation excessive de pesticides chimiques qui manquent de toxicité spécifique a provoqué une série de problèmes environnementaux et de santé publique. L'intérêt de la recherche vers de nouveaux biopesticides naturels avec de nouveaux modes d'actions vise à un meilleur équilibre entre l'efficacité des pesticides et la réduction des méfaits possibles pour l'environnement et les humains. Les plantes sont une source importante de biopesticides. Les acides chlorogéniques (CQA), isolés à partir de diverses plantes et présentent in vivo et in vitro un large spectre d'activités biologiques, ont attiré l'attention avec un potentiel comme biopesticides basé sur la toxicité brevetée de l'acide 3,5-di-O-caféoylquinique contre les larves de Myzus persicae. L'étude des propriété insecticides notamment la mode d'action et l'étude de certaines relations structure-activité pourrait bénéficier de la synthèse de différents dérivés et analogues de CQA. Des analogues des acides 4-désoxy-3,5-dicinnamoy quiniques et 3,4- et 4,5-dicinnamoylquiniques naturels ont été synthétisés. Sept analogues dans la série 4-désoxy ont été soumis à des essais insecticides et deux composés présentent une activité insecticide plus élevée que l'acide 3,5-dicaféoylquinique naturel. Comme perspectives à ce travail, confirmer l'activité des composés synthétisés sur d'autres espèces de pucerons d'importance agronomique pourrait être réalisé. De plus, d’autres collaborations avec des biologistes pourraient être établies afin d’évaluer d'autres activités des composés synthétisés ou les utiliser comme outils pour étudier des mécanismes de biosynthése
The use of conventional pesticides, especially the synthetic chemical pesticides, has greatly reduced the crop losses and gained a commercial success. However, the excessive use of pesticides lacking toxic specificity has caused a series of environmental and public health problems. The research interest toward new naturally-occurring biopesticides with novel modes of actions aims at a better balance between the efficiency of pesticide and reducing possible harms to environment and humans. Botanicals are an important source of biopesticides. Cinnamoyl quinic acids (CQA), isolated from various plants and shown to exhibit in vivo and in vitro a wide spectrum of biological activities, have attracted the attention with potential as biopesticides based on the patented toxicity of 3,5-di-O-caffeoylquinic acid against the larvae of Myzus persicae. The investigation of the insecticidal activity of CQA including their mode of action and the study of some structure-activity relationships could benefit from the synthesis of different CQA derivatives and analogs. A series of natural CQA derivatives natural 3,4- and 4,5-dicinnmamoylquinic acid derivatives but also analogs like 4-deoxy-3,5-dicinnamoylquinic acids were so synthesized. Seven targeted 4-deoxy CQA analogs were subjected to insecticidal assays, and two compounds were found to exhibit higher insecticidal activities than natural 3,5-dicaffeoylquinic acid. As perspectives to this work, confirming the activity of the synthesized compounds on other aphid species of agronomic importance could be performed. Furthermore, other collaborations could be established with biologists dedicated to measure other bioactivities of the synthesized compounds or use them as tools to investigate various biological pathways

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Hinchliffe, Gareth. "Novel biopesticides based on recombinant avidin for protection of crops against insect pests." Thesis, Durham University, 2012. http://etheses.dur.ac.uk/6907/.

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Farmers are required to increase their food productivity to meet the demand from a continually enlarging population. A major constraint on meeting this requirement is the damage created by insect pests. Agricultural pests and associated diseases destroy 30%-40% of the world’s crop produce. The withdrawal of broad-spectrum chemical insecticides, the threat of the development of resistance in insect pests to remaining compounds and the possibility of new pest species spreading into the UK as a result of environmental change have prompted research into alternative pesticides. Protein-based insecticides offer the possibility of producing compounds that are specific to pest species and environmentally benign. The production of orally active insecticidal fusion proteins, containing toxins from Segestria florentina (tube-web spider) or Mesobuthus tamulus (Indian red scorpion) fused to a ‘carrier’ protein (snowdrop lectin; Galanthus nivalis agglutinin; GNA) which transports them across the insect gut epithelium, has shown that recombinant protein expression systems and protein engineering techniques can be used to produce novel insecticidal proteins. The main aim of the work described in this thesis is to extend this technology. Avidin, a biotin-binding protein known to be insecticidal, was evaluated as a possible ‘carrier’ protein. Recombinant avidin was produced in high yields using Pichia pastoris and was compared to the native egg white protein. Recombinant avidin has insecticidal activity towards hemipteran plant pests. It was highly toxic to Acyrthosiphon pisum (pea aphid) when fed in liquid artificial diet, causing 100% mortality after four days when present at concentrations ≥0.25mg/ml (250ppm). The toxicity towards A. pisum was prevented by biotin supplementation of the diet. In contrast, recombinant avidin had no significant effects on the survival of Sitobion avenae (cereal aphid) at concentrations up to 2mg/ml (2000ppm) in liquid diet. Analysis of genomic DNA showed that symbionts from both aphid species lack the ability to synthesise biotin de novo. Cereal aphids appear to be less sensitive to sub-optimal levels of biotin and possess a more effective system for scavenging biotin from recombinant avidin in the diet. Avidin is readily transported to the haemolymph of lepidopteran larvae after feeding, which suggested that it might replace GNA in synthetic insecticidal fusion proteins. Numerous attempts were made to produce a fully functional insecticidal avidin-based fusion protein containing scorpion or spider toxins by expression as recombinant proteins in P. pastoris but, following tests against Mamestra brassicae (cabbage moth) larvae, the fusion proteins were found to be non-toxic. The lack of toxicity was most likely due to incorrect folding of the toxin component of the fusion, since the avidin component was functional. Avidin fed to A. pisum was found to bind to the stomach region of the gut after ingestion and was retained for at least 72 hours. Feeding conjugates of avidin with fluorescently labelled biotin, or a fluorescently labelled, biotinylated peptide, showed that the conjugated compound was also retained in the aphid gut after feeding. A conjugate between avidin and biotinylated leucomyosuppressin (LMS), a myoinhibitory peptide hormone that affects gut contractions in insects, was prepared and fed to aphids. The avidin : biotin-LMS conjugate had insecticidal activity towards A. pisum when fed in diet at levels which neither of the components (avidin or biotin-LMS) caused significant mortality. It was hypothesised that binding to the gut, through the avidin moiety, was responsible for the observed oral toxicity of the avidin : biotin-LMS conjugate. The same principle was applied to lepidopteran larvae. A conjugate between avidin and biotinylated allatostatin was prepared and fed to M. brassicae larvae. The avidin : biotin-allatostatin was non-toxic, most likely due to cleavage between the biotin molecule and allatostatin as a result of the high levels of gut proteolysis in lepidoptera. Avidin conjugates of peptides that have little or no oral toxicity to insects, as a result of restricted access to sites of action, could have the potential to form a novel class of insecticidal compounds.

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Alatawi, Aishah Mohammed M. "Novel biopesticides targeting the neuromuscular system of the peach potato aphid Myzus persicae." Thesis, University of Newcastle upon Tyne, 2016. http://hdl.handle.net/10443/3518.

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The amount of biopesticides currently used in pest control is still below 1% of the global pesticide market, with environmentally damaging products constituting the majority of all commercial insecticides. There is thus an increased need for biopesticides, including those from invertebrate venoms, which are often highly specific. One example of this is to use a fusion protein approach where a peptide-toxin is fused to a carrier protein, in this instance GNA, which has the capability of crossing the insect gut epithelium allowing inhibitory molecules of the neuromuscular system to be delivered to these remote sites of action via oral ingestion. In this study, five variants of spider Segestria florentina toxin (SFI) fused to snowdrop lectin (Galanthus nivalis agglutinin; GNA) were successfully expressed in Pichia pastoris X33 and subsequently purified. To improve the level of expression of the intact recombinant protein SFI1/GNA, an expression vector construct containing two gene copies was assembled. Insecticidal activities of all these novel fusion proteins were demonstrated by oral feeding to Myzus persicae. SFI1, SFI3, SFI5, SFI6, and SFI8 GNA-based fusion proteins (0.1 mg/ml), which target voltage-gated ion channels in the insect CNS, caused significant mortality to M. persicae compared to GNA alone. LC50 values for the variants 2XSFI1/GNA, SFI5/GNA and SFI8/GNA were 0.006 mg/ml, 0.038 mg/ml, and 0.08 mg/ml respectively. The GNA-based fusion proteins expressing -conotoxin E1 from cone snails, which target nicotinic acetylcholine receptors, was also successfully expressed in P. pastoris; in these, GNA was at the N-terminus and the toxin at the C-terminus. The LC 50 values for the GNA/-conotoxin E1 was 8 μg/μl. The results demonstrate that these candidate molecules show promise for future development as bio-pesticides.

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Porto, Rafael Silveira 1989. "Conyza canadensis : determinação de compostos bioativos e avaliação da atividade antifúngica." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249439.

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Orientadores: Susanne Rath, Sonia Claudia do Nascimento de Queiroz
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: O Brasil é um dos maiores produtores de frutas do mundo, no entanto, estima-se que doenças pós-colheita possam gerar perdas de até 50% em sua produção. A forma mais comum de tratamento para essas doenças envolve a aplicação de fungicidas sintéticos. Contudo, nos últimos anos, a demanda por tratamentos alternativos tem crescido, com destaque para o uso de biopesticidas, produtos desenvolvidos a partir de plantas, microrganismos e insetos. Este trabalho teve como objetivo investigar a presença dos compostos bioativos (4Z)-lachnophyllum lactona, (4Z,8Z)-matricaria lactona e (2Z,8Z)-matricaria ester nos espécimes brasileiros da planta Conyza canadensis, bem como avaliar a atividade antifúngica dessas substâncias isoladas contra diversos fungos associados a doenças pós-colheita de frutas. Por cromatografia flash preparativa foi possível isolar a (4Z)-lachnophyllum lactona e a (4Z,8Z)-matricaria lactona a partir de extratos da planta obtidos com diclorometano. Os compostos foram caracterizados por GC-MS/MS, NMR 1H e 13C, 1H-1H COSY e 1H-13C HSQC. Foram realizados ensaios de difusão em disco com 10 fungos filamentosos causadores de doenças pós-colheita em frutas. Os fungos Aspergillus niger, Cladosporium spp. e Penicillium digitatum se mostraram susceptíveis ao tratamento e, para eles, a concentração mínima inibitória dos compostos variou de 32 a 64 µg mL-1. Também foi desenvolvido um método de extração empregando água quente pressurizada, no qual foram otimizados os parâmetros de temperatura (100 °C), tempo de ciclo (1 min) e número de ciclos (quatro). Com essa técnica foi possível obter um rendimento de 1,46 mg g-1 e 0,24 mg g-1 para a (4Z)-lachnophyllum lactona e a (4Z,8Z)-matricaria lactona, respectivamente. O extrato aquoso da Conyza canadensis pode ser aplicado diretamente nos frutos com a vantagem de não conter resíduos de solventes orgânicos tóxicos
Abstract: razil is one of the largest fruit producers in the world. Nevertheless, it is estimated that postharvest diseases can lead to losses of up to 50% in its production. The most common treatment for these diseases involves the application of synthetic fungicides. Nonetheless, in recent years, the demand for alternative treatments has increased, especially for the use of biopesticides, products developed from plants, microorganisms and insects. This study aimed to investigate the presence of the bioactive compounds (4Z)-lachnophyllum lactone, (4Z,8Z)-matricaria lactone and (2Z,8Z)-matricaria ester in Brazilian specimens of the weed Conyza canadensis, as well as to evaluate the antifungal activity of these isolated substances against several fungi associated with postharvest diseases of fruits. With the use of preparative flash chromatography it was possible to isolate (4Z)-lachnophyllum lactone and (4Z,8Z)-matricaria lactone from plant extracts obtained with dichloromethane. The compounds were characterized by GC-MS/MS, NMR 1H e 13C, 1H-1H COSY and 1H-13C HSQC. Disk diffusion assays were performed in order to investigate the activity of the isolated compounds against 10 filamentous fungi regarded as common postharvest pathogens of fruits. Aspergillus niger, Cladosporium spp. and Penicillium digitatum proved susceptible to the treatment and, for them, the minimum inhibitory concentration of the compounds varied from 32 to 64 µg mL-1. An extraction method using pressurized hot water was also developed, in which the parameters of temperature (100 ° C), cycle time (1 min) and number of cycles (four) were optimized. By using this technique, it was possible to obtain a yield of 1.46 mg g-1 and 0.24 mg g-1 for the (4Z)-lachnophyllum lactone and (4Z,8Z)-matricaria lactone, respectively. The aqueous extract of Conyza canadensis can be applied directly on fruits with the advantage of not containing residues of toxic organic solvents
Mestrado
Quimica Analitica
Mestre em Química

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Júnior, Giovani Marcio Coura. "Análise integrada das variáveis virulência e produção de conídios na seleção de fungos entomopatogênicos para o desenvolvimento de biopesticidas." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-16082017-135321/.

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Os fungos entomopatogênicos do gênero Metarhizium e Beauveria compreendem um importante grupo de patógenos de artrópodes-praga. A seleção de isolados de fungos promissores é a primeira e uma das mais importantes etapas no desenvolvimento de um biopesticida, pois alguns isolados podem apresentar alta virulência e não necessariamente boa produção em substrato e vice-versa, sendo interessante a combinação desses dois parâmetros para a viabilidade comercial de um produto. A dificuldade de criação ou manutenção de algumas espécies de pragas em laboratório é um limitante para a condução de testes de virulência, tornando-se interessante a utilização de espécies modelo, de fácil criação, nas etapas preliminares de seleção. Nesse sentido, este estudo objetivou selecionar isolados com alta produção de conídios e virulência, comparando a eficiência de controle de M. anisopliae e B. bassiana às pragas alvo Mahanarva fimbriolata e Bemisia tabaci Biótipo B, respectivamente, com a mortalidade em Tenebrio molitor. Inicialmente, foram selecionados 50 isolados a partir de 100 isolados de cada gênero, baseado em avaliações visuais do crescimento e esporulação em meio de cultivo em placas de Petri. Estes isolados selecionados foram cultivados em arroz parboilizado para quantificação do rendimento produtivo de conídios. Os 25 isolados mais produtivos de cada espécie de fungo foram utilizados nos bioensaios com T. molitor. Posteriormente, os cinco isolados que causaram maior e menor mortalidade de cada gênero, foram utilizados nos bioensaios com as respectivas pragas-alvo. A variação no rendimento de conídios de Beauveria spp., foi de 0,3 a 7,7 x 109 conídios.grama de arroz-1 e de Metarhizium spp. foi de 0,1 a 2,5 x 109 conídios.grama de arroz-1. A mortalidade confirmada de larvas de T. molitor por Beauveria spp., variou de 5,5 a 96,4% e por M. anisopliae variou de 29,1 a 89,1%. Alguns isolados causaram mortalidade elevada tanto no inseto modelo quanto na praga-alvo, porém, não foi verificada uma relação entre a virulência para as duas espécies. Da mesma forma, não foi observada associação entre os parâmetros produção de conídios e virulência. O isolado ESALQ 4958 de B. bassiana se destacou nos dois bioensaios apresentando mortalidades elevadas de ninfas de B. tabaci Biótipo B. Nos bioensaios utilizando ninfas de M. fimbriolata, ESALQ 1641 foi o isolado que apresentou os maiores percentuais de mortalidade nos dois bioensaios. Analisando conjuntamente as variáveis produção de conídios e virulência a T. molitor e a espécie alvo, os isolados ESALQ 540 (B. bassiana) e ESALQ 1116 (M. anisopliae) se destacaram por apresentarem valores elevados para todas as variáveis de interesse. Os resultados reforçam a necessidade de uma análise conjunta destas variáveis com um peso diferenciado para cada variável na seleção de isolados para utilização em produtos microbianos para o controle de pragas.
The genus Metarhizium spp. and Beauveria spp. are important entomopathogenic fungi used to control arthropod pests. The selection of promising fungal isolates is the first and one of the most important steps on the development of a biopesticide, since some isolates may present high virulence and not necessarily good production in substrate and vice-versa, being the combination of these two parameters important for the commercial viability. Difficulties of rearing or maintaining some species of pests in laboratory are limitations for the conduction of virulence tests, justifying the use of easy to breed model species on the preliminary steps of selection. Therefore, this study aimed to select isolates with high conidia production and virulence, comparing the control efficiency of M. anisopliae and B. bassiana to the target pests, Mahanarva fimbriolata and Bemisia tabaci biotype B, respectively, with mortality in Tenebrio molitor. At first, 50 isolates were selected from 100 isolates of each genus, based on growth and sporulation in culture medium on Petri dishes. These isolates were grown in parboiled rice to quantify the yield of conidia. The 25 most productive isolates of each fungus species were used in the bioassays with T. molitor. After, the five isolates that caused higher and lower mortality of each genus were used in the bioassays with the respective target pests. Beauveria spp. conidia yield ranged from 0.3 to 7.7 x 109 conidia.grams of rice-1 and Metarhizium spp. from 0.1 to 2.5 x 109 conidia.gram of rice-1. The confirmed mortality of T. molitor larvae by Beauveria spp. varied from 5.5 to 96.4% and M. anisopliae varied from 29.1 to 89.1%. Some isolates caused high mortality in both, model insect and the target pest; however, no relationship between the virulence of both species was observed. Similarly, there was no association between the parameters conidia production and virulence. The B. bassiana isolate ESALQ 4958 in both bioassays presented high mortalities of B. tabaci Biotype B. In bioassays using M. fimbriolata nymphs, ESALQ 1641 was the isolate that presented the highest mortalities in both bioassays. Analyzing the variables, conidia production and virulence to T. molitor and the target species, the isolates ESALQ 540 (B. bassiana) and ESALQ 1116 (M. anisopliae) showed high values for all variables of interest. The results reinforce the necessity of a joint analysis of these variables with different weight for each one in the selection of isolates, aiming to use them in microbial products for pest control.

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Tranier, Marie-Stéphane. "Production de biopesticides pour lutter contre les nématodes à galles des cultures intensives sous abris de tomates au Maroc." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4361.

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Ce projet industriel porte sur la production de biopesticides actifs sur les nématodes à galles des cultures intensives de tomates sous abris au Maroc. Les travaux portent sur (i) l’isolement de souches de champignons filamenteux nématophages provenant des sols des cultures infectées par les nématodes, (ii) la réalisation de cultures de ces souches sur un milieu adapté à la Fermentation en Milieu Solide, technique optimale à la biologie des champignons filamenteux et présentant des avantages technologiques et économiques exploitables à une échelle industrielle, (iii) la production de biomasse et de molécules actives extrapolable à une échelle semi-industrielle, (iv) la mise en œuvre d’essais agronomiques pour valider l’efficacité d’un biopesticide produit par FMS dans des dispositifs innovants.24 souches de champignons filamenteux nématophages ont été isolées à partir des sols des cultures intensives de tomate sous serre au Maroc, mais également à partir de produits commerciaux. Le milieu FMS composé de sous-produits agro-industriels permettant une production de l’ordre de 1010 spores par gramme de substrat PS a été validé, et les conditions de cultures des souches établies. 4 dispositifs de Fermentation en Milieu Solide dont un à usage unique, de 300 à 5 000 g ont été mis au point, et ont été protégés par 3 brevets. Enfin, des essais agronomiques de différentes tailles (quelques billons à plusieurs hectares de tomates) ont été mis en place au Maroc de manière à valider l’utilisation de champignons filamenteux actifs contre les nématodes à galles comme étant une alternative écologique à l’utilisation de produits chimiques
This industrial project involves the production of biopesticides active against root knot nematodes of intensive greenhouse tomato cultures in Morocco. This work focuses on (i) the isolement of nematophagous filamentous fungi from agricultural soils infected with nematodes, (ii) the cultures of these strains on a suitable medium for Solid State Fermentation (SSF), which is the optimal cultural technique for filamentous fungi, presenting technological and economical benefits at an industrial scale, (iii) the production of biomass and active molecules at a semi-industrial scale, (iv) the installation of agronomic assays to validate the effectiveness of a biopesticide production by SSF in innovative devices.24 nematophagous filamentous fungi strains were isolated from intensive greenhouse tomato culture soils, but also from commercial products. The SSF medium composed of agro-industrial by-products allowing a production of about 1010 spores per gram of DW substrate was validated, and the culture conditions of these strains were established. 4 SSF devices including one at single use, from 300 to 5 000 g DW substrate were developed, and were protected by 3 patents. Finally, agronomic assays of different sizes (from few lines to several hectares of tomatoes) were carried out in Morocco in order to validate the use of active filamentous fungi against root-knot nematodes as an ecological alternative to the use of chemical products

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Al-Alam, Joséphine. "Polluants organiques : analyse, application au « biomonitoring » environnemental et introduction des biopesticides (algues marines) comme alternative." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAF019.

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Dans un contexte où les inquiétudes environnementales dues à la pollution sont grandissantes à l’échelle globale, la surveillance de la pollution environnementale constitue un enjeu majeur de recherche afin de préserver au mieux un environnement sain et durable. En effet, la surveillance responsable et continue de l’environnement accompagnée par le développement d’alternatives de lutte « verte » contre les nuisibles, pourrait certainement ralentir voir inhiber la propagation de polluants néfastes pour l’ensemble de la biosphère. Dans ce contexte, les objectifs principaux de cette thèse visent d’une part à caractériser la qualité de l’air par une approche basée sur le biomonitoring, et d’autre part à développer un biopesticide d’origine algale permettant la protection des agrumes en post-récolte comme un exemple d’alternative à l’usage des traitements chimiques classiques. Pour répondre au premier objectif, des méthodes d’extraction multi résidus ont dû être développées. Ces méthodes ont été soit spécifiques d’une famille de pesticides tel que les dithiocarbamates, soit plus large et plus générale en considérant de nombreux polluants comme des pesticides, des HAPs et des PCBs. Ces dernières ont été basées soit sur l’ASE-SPE-SPME, soit sur le QuEChERS-SPME, et ont formé le socle des études de biosurveillance environnementale entreprises. Ces études de surveillance ont permis l’évaluation des modifications spatio-temporelles de la qualité de l’air grâce à des espèces naturelles ayant un rôle de capteurs biologique de la pollution environnementale et permettant par la suite l’estimation de la pollution dans des zones bien définies. Pour répondre au second objectif, des extraits aqueux d’algues vertes, Ulva linza et Ulva lactuca, ont été préparés et testés comme antifongiques in vivo et in vitro afin d’étudier leur aptitude à inhiber le développement de Penicillium digitatum sur des agrumes en post récolte. Un potentiel de protection des agrumes en poste-récolte contre ce champignon a été mis en évidence, donnant effectivement l’espoir à la fiabilité de cette approche comme alternative biologique pour le remplacement des pesticides chimiques potentiellement toxiques
In a context where environmental concerns due to pollution are growing on a global scale, monitoring of environmental pollution is a major research challenge in order to preserve as much as possible a healthy and sustainable environment. Indeed, the responsible and continuous monitoring of the environment escorted by the development of "green" pest control alternatives could certainly decelerate or even inhibit the spread of harmful pollutants into the entire biosphere. In this context, the main objectives of this thesis are intended firstly to characterize air quality by a biomonitoring-based approach and, secondly, to develop a biopesticide of algal origin, that allows the protection of post-harvested citrus fruit, as an alternative to the use of conventional chemical treatments. In order to answer the first objective, multi-residues extraction methods were developed. These methods were either specific to a family of pesticides such as dithiocarbamates or wider and more general regarding numerous pollutants such as pesticides, PAHs and PCBs. The latter were based either on the ASE-SPE-SPME, or on the QuEChERS-SPME, and formed the base of environmental biomonitoring studies undertaken. These monitoring studies allowed the assessment of spatial and temporal changes in air quality through natural species acting as biological sensors of environmental pollution and subsequently allowing the estimation of pollution in well-defined areas. To answer the second objective aqueous extracts of green algae, Ulva linza and Ulva lactuca, were prepared and tested as in vivo and in vitro antifungal agents, in order to study their ability to inhibit the development of Penicillium digitatum on post-harvested citrus fruits. A potential of post-harvested citrus fruits’ protection against this fungus was proved, giving hope to the reliability of this approach as a biological alternative for the replacement of potentially toxic chemical pesticides

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Van, Munster Manuela. "Caractérisation biologique et moléculaire de virus infectant les pucerons et évaluation de leur potentiel comme biopesticides." Montpellier 2, 2002. http://www.theses.fr/2002MON20160.

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Boulogne, Isabelle. "Evaluation du potentiel insecticide et antifongique sur Acromyrmex octospinosus (Reich) d'une sélection de plantes à usages etnopharmacologiques TRAMIL." Thesis, Antilles-Guyane, 2011. http://www.theses.fr/2011AGUY0469/document.

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Les attines sont des fourmis champignonnistes dans la zone allant des Etats-Unis à l'Argentine en passant par la Caraïbe. Les dégâts causés par ces ravageurs sont considérables et estimés à plusieurs millions de dollars par an. Elles sont de ce fait considérées comme l'un des premiers fléaux de l'agriculture de la zone (Cameron & Riggs, 1985 ; Fowler et al., 1986). En Guadeloupe, la "fourmi manioc" (Acromyrmexoctospinosus Reich) cause de nombreux dommages, aussi bien pour l'agriculture que dans les milieux naturels. Les dégâts occasionnés par ces fourmis ont nécessité l'utilisation de pesticides de synthèse. pour tenter de les combattre. La dangerosité de ces substances pour les milieux naturels et anthropisés ainsi que pour la santé publique est un contexte favorable à l'exploration de nouvelles pistes telles que l'utilisation de plantes à usages phytosanitaires. L'objet principal de cette thèse consiste à savoir si on peut déceler à partir de l'ethnopharmacologieTRAMIL des usages permettant de combattre cette fourmi et son symbiote fongique, Leucocoprinuss 'gongylophorus (Heim) MoeIler. Les protocoles retenus et présentés dans ce travail permettent d'observer les effets des usages de plantes choisis sur la survie et le comportement des insects et sur la croissance du symbiote. Ils ont été sélectionnés pour leur potentialité à mettre en évidence les différents types d'effets des extraits végétaux (insecticide par contact, insectifuge, toxique par ingestion, fongistatique ou fongicide). Six usages traditionnels issus de cinq plantes sont testés sur la fourmi: Mammea americana L., Nerium oleander L., Nicotiana tabacum L., Rollinia mucosa (Jacq.) Baill. et Trichilia pallida Sw. Cinq autres usages traditionnels sont testés sur le champignon : Allium cepa L., Allium sativum L., Lycopersicom esculentum Mill., Manihot esculenta Crantz et Senna alata (L.) Roxb. Les resultants obtenus permettent de dégager quelques pistes de lutte intéressantes contre ce ravageur
Leaf-cutting ants are fungus-growing ants.Their geographie distribution ranges from southern United States to northern Argentina, incIuding the West Indies, Economic losses due to these ants were estimated at several million dollars per year. The latter statement makes they are considered as one of the most important pest species of the agricultural productions (Cameron & Riggs, 1985 ; Fowler et al., 1986). In (Guadeloupe, the most important invasive pest species which caused important losses in forests, gardens and field crops is 'cassava ant' (Acromyrmex octospinosus Reich). These huge losses required to use, synthetic chemical pesticides to control these leaf-cutting ants, the consequence of which is, irreversible' injuries on environment and on human health. As a matter of fact, this situation has prompted an increasing interest in alternative methods for pest control like plants with pesticide used. The main objective of this thesis is to know if traditional ethnopharmacological TRAMIL uses could help to fight against this ant and against the symbiotic fungus, Leucocoprinus gongylophorus (Heim) . Moeller. Methods used and presented in this work aIIowed to observe effects of selected plant uses on mortality and insect's behavior. The protocols performed were selected for their potentiality to detect the different types of insecticidal effects (contact toxicity, repellent effect, toxicity by ingestion, fungicidal or fungistatic). Six traditional plant uses of five plants were tested on the ant : Mammea americana L., Nerium oleander L., Nicotiana tabacum L.,Rollinia mucosa (Jacq) Baill. and Trichilia pallida Sw.Five other plants uses were tested on the fungus:Allium cepa L.,Lycopersicon esculentum Mill.,Manihot esculenta Crantz and Senna alata (L.) Roxb.The obtained résults provide us with some interesting trails to fight against this pest

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Zanardi, Odimar Zanuzo. "Mecanismos associados à ocorrência de surtos populacionais e manejo de Panonychus citri (McGregor) (Acari: Tetranychidae) em pomares cítricos." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-04052015-152001/.

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O ácaro purpúreo, Panonychus citri (McGregor) (Acari: Tetranychidae), ainda é considerado uma praga de importância secundária nos pomares cítricos brasileiros. No entanto, nos últimos anos, sua população vem aumentando consideravelvente devido a ocorrência de surtos populacionais do ácaro que, na maioria das vezes, causam danos consideráveis nas plantas e exige que medidas de controle sejam adotadas. Neste sentido, objetivou-se com esse estudo, avaliar os níveis de suscetibilidade de diferentes espécies e variedades de plantas cítricas no desenvolvimento e reprodução de P. citri; elucidar as causas biológicas, comportamentais e demográficas responsáveis pelo aumento populacional do ácaro após a aplicação de inseticidas piretroides; demonstrar os impactos desses inseticidas sobre o predador Iphiseiodes zuluagai Denmark & Muma (Acari: Phytoseiidae) e verificar a atividade de biopesticidas à base de azadirachtin, annonin e matrine como tática adicional de controle de P. citri. Os resultados demonstraram que as espécies e variedades de plantas cítricas apresentaram diferentes níveis de suscetibilidade ao ácaro P. citri. A maior taxa de crescimento populacional do ácaro ocorreu em laranjeira Valência e limoeiro Siciliano quando comparados as laranjeiras Pera, Natal e Hamlin e tangerineira Ponkan, demonstrando que esses hospedeiros podem contribuir para o aumento populacional do ácaro. Entre os hospedeiros avaliados, laranjeira Hamlin proporcionou menor taxa de crescimento de P. citri, demonstrando que essa variedade é menos favorável ao desenvolvimento e reprodução do ácaro quando comparado aos demais hospedeiros testados. Além das diferentes taxas de crescimento do ácaro proporcionado pelas plantas hospedeiras, o uso de inseticidas piretroides e neonicotinoides também contribuem para o aumento populacional do ácaro P. citri. Com base nos resultados, o aumento na dispersão e na deterrência de alimentação e oviposição dos ácaros proporcionados pelos inseticidas piretroides, a insensibilidade dos diferentes estádios de desenvolvimento do ácaros aos inseticidas neonicotinoides e ao efeito hormese, caracterizado pelo aumento na fecundidade das fêmeas expostas principalmente aos inseticidas piretroides deltamethrin e lambda-cyhalothrin e o neonicotinoide imidacloprid foram as principais causas biológicas e comportamentais associadas ao aumento populacional de P. citri. Por outro lado, os inseticidas esfenvalerate e thiamethoxam não ocasionaram aumento significativo nos parâmetros demográficos do ácaro quando comparado aos demais tratamentos avaliados. Além das alterações na abundância populacional de P. citri, os inseticidas piretroides ocasionaram redução na sobrevivência e/ou reprodução do predador I. zuluagai, demonstrando que esses produtos podem afetar a densidade e a efetividade do predador no controle biológico de artrópodes-praga nos pomares cítricos. Diante do aumento na abundância e na frequência de surtos populacionais do ácaro P. citri após a aplicação de inseticidas piretroides e neonicotinoides e dos impactos ocasionados sobre o predador I. zuluagai novas alternativas de controle de P. citri foram investigadas no presente estudo. Os resultados demonstraram que o uso de biopesticidas à base de azadirachtin, annonin e matrine apresentaram alta atividade contra P. citri e pode ser uma importante alternativa para uso no manejo do ácaro em substituição ou rotação com acaricidas sintéticos. As informações obtidas no presente estudo contribuirão para subsidiar os programas de manejo integrado de pragas nos pomares cítricos.
The citrus red mite, Panonychus citri (McGregor) (Acari: Tetranychidae), is still considered a pest of secondary importance in Brazilian citrus groves. However, in recent years, its population has been increasing considerably due to occurrence of mite outbreaks that, in most cases, cause considerable damage to the plants and requires the adoption of control measures. Thus, the purpose of this study was to evaluate the susceptibility levels of different species and varieties of citrus plants to the development and reproduction of P. citri; to elucidate the biological, behavioral and demographic causes responsible for mite population growth after application of pyrethroids and neonicotinoids insecticides; to demonstrate the impact of these pesticides on Iphiseiodes zuluagai Denmark & Muma (Acari: Phytoseiidae) predator and to verify the activity of azadirachtin-, annonin-, and matrine-based biopesticides as additional tactic of P. citri control. The results showed that the species and varieties of citrus plants showed different susceptibility levels to P. citri mite. The highest growth rates of mite population occurred in Valencia orange and Sicilian lemon compared to Pera, Natal and Hamlin oranges and Ponkan mandarin, demonstrating that these hosts can contribute to mite population growth. Among the hosts evaluated, Hamlin sweet orange showed lower growth rate of P. citri, showing that this variety is less favorable to the development and reproduction of the mite when compared to other hosts tested. In addition to the different growth rates of the mite provided by host plants, the use of pyrethroid and neonicotinoids insecticides also contributed to the P. citri population growth. Based on the results, the increase in dispersion and feeding and oviposition deterrence of the mites provided by the pyrethroids insecticides, the insensibility of the different development stages of mites to neonicotinoids insecticides and hormesis effect, characterized by increasing the fecundity of female exposed mainly to insecticides deltamethrin and lambda-cyhalothrin pyrethroids and imidacloprid neonicotinoid were the main biological and behavioral causes associated to population growth of P. citri. On the other hand, esfenvalerate and thiamethoxam insecticides did not cause a significant increase in the demographic parameters of the mite when compared to other treatments. Besides the changes in population abundance of P. citri, the pyrethroid insecticides caused reduction in survival and/or reproduction of I. zuluagai predator, demonstrating that these products can affect density and effectiveness of the predator in the biological control of arthropod pests in citrus groves. Given the increase in abundance and frequency of outbreaks of P. citri after application of pyrethroid and neonicotinoids insecticides and of impacts caused to I. zuluagai predator new management alternatives to P. citri control were investigated in this study. The results showed that the use of azadirachtin-, annonin-, and matrine-based biopesticides had high activity against P. citri and may be an important alternative in the management of the mite in replacement or rotation with synthetic acaricides. The information obtained in this study will contribute to support the integrated pest management programs of citrus groves.

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Soltani, Dashtbozorg Soroosh. "Microbial Rhamnolipids as Environmentally Friendly Biopesticides: Congener Composition Produced, Adsorption in Soil, and Effects on Phytophthora sojae." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1438175115.

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Palumbo, John C. "Knockdown and Residual Efficacy of Biopesticides and Reduced-Risk Insecticides against Western Flower Thrips in Romaine Lettuce." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/214928.

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Three separate field trials over two years were conducted to evaluate the comparative knockdown and residual efficacy of several conventional, Reduced risk and biopesticide compounds against western flower thrips in romaine lettuce. These trials consistently demonstrated that both Lannate-pyrethroid combinations and Success provided significant knockdown and residual control of thrips adults and larvae when compared to the other spray biopesticide treatments. Unfortunately, the biopesticide alternatives at best provided poor to marginal efficacy against western flower thrips. The implication of these results on desert lettuce production and resistance management programs is discussed.

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Couleru, Silvia. "Phéromones des insectes : rôles dans la communication chimique et applications pratiques contre les insectes nuisibles en agriculture." Bordeaux 2, 2000. http://www.theses.fr/2000BOR2P057.

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Ng, Kenneth K. "Investigation of Bacillus subtilis as a Biopesticide Against Botrytis cinerea." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/717.

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The objective of this thesis was to investigate BiOWiSHTM-Aqua, a commercial dry solid formulation containing a consortium of bacteria and yeast, as a biopesticide for treatment of Botrytis cinerea, a gray mold that affects strawberries. BiOWiSHTM-Aqua was compared with another commercial product specifically used as a fungicide and bacteriocide, Serenade® Garden Disease Control Spray (concentrated Bacillus subtilis strain QST 713). Both laboratory tests as well as in vivo lab tests were conducted. BiOWiSHTM-Aqua results varied widely from plate to plate, regardless of experimental conditions. In some of these plates, inhibition zones were observed around colonies from BiOWiSHTM-Aqua, indicating efficacy. The organism responsible for the inhibition zones of B. cinerea growth was isolated from BiOWiSHTM-Aqua, and 16s rRNA analysis identified this culture as a strain of B. subtilis. This strain was designated as B. subtilis ssp. KLB. The B. subtilis KLB concentration required to completely inhibit B. cinerea was 9.1x104 CFU/mL when B. subtilis KLB was inoculated 48 hours before B. cinerea, 1.3x105 CFU/mL at 24 hours, and 3.2x106 CFU/mL when both were inoculated at the same time. Various preliminary experiments using B. subtilis KLB were also conducted to investigate its economic feasibility, to characterize the organism, and to test its post-harvest in vivo viability. B. subtilis KLB cell concentration was 1.6x109 CFU/mL in a bioreactor with LB at the end of the log growth phase. B. subtilis KLB achieved cell concentrations as high as 5x109 CFU/mL in shake flasks with food-grade tapioca as a carbon source. Inoculation of B. subtilis KLB on post-harvest strawberries did not have an effect on Botrytis infection rates compared to the negative control. These various experiments were the first step in research to potentially produce B. subtilis KLB on a commercial scale.

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Diakité, Abdoulaye. "Extraction et caractérisation des extraits cireux de graines de Jatropha curcas pour application biopesticide." Master's thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/32865.

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Jatropha curcas L. est une espèce trouvée dans presque toutes les régions tropicales. Ces graines contiennent de l’huile qui convient à la production de biodiesel et par conséquent, elle a reçu un intérêt mondial en tant que source de biocarburant. Cependant, à ce jour Jatropha curcas n’a pas atteint son plein potentiel. Outre son utilisation pour la production de biodiesel, le développement d’autres sous-produits de graines de Jatropha comme la cire s’ajoute à la valeur économique de cette plante. Cependant, aucune étude détaillée n’a été apportée sur le rendement en cire de graines de Jatropha et ses utilisations dans la production de biopesticide. La présente étude a révélé que le rendement en cire de graines de Jatropha par les méthodes d’extraction utilisant le n-hexane, l’eau bouillante et l’azote liquide, était de 0,11%, 0,03% et 0,02%, respectivement. L’analyse des thermo grammes DSC par calorimétrie différentielle à balayage montre que la cire extraite par l’hexane est plus complexe indiquant la présence de plusieurs composés différents, comparée aux cires obtenues par les deux autres méthodes. Ceci est en accord avec les résultats obtenus au microscope électronique par balayage qui montrent moins de cire sur la surface et l’intérieur de graines de Jatropha traitées à l’hexane par rapport aux deux autres solvants. Le test biologique exploratoire effectué a révélé que les extraits cireux devraient posséder une certaine propriété biocide. Ils induisaient 100 % de mortalité des larves de stade 4 de Choristoneura fumiferana à une concentration de 20%.
Jatropha curcas L. is a species found in almost all tropical regions. The seeds of Jatropha curcas contain oil that is suitable for biodiesel production and therefore has received global interest as a source of biofuel. However, so far Jatropha curcas has not reached its full potential. In addition to its use for biodiesel production, the development of other Jatropha seed by-products such as wax will add to the economic value of this plant. No detailed studies have been conducted on Jatropha seed wax performance and its uses in biopesticide production. The present study revealed that the wax yield of Jatropha seeds was 0.11%; 0.03% and 0.02% respectively for extraction methods using n-hexane, boiling water and liquid nitrogen. Differential scanning calorimetry analysis of the DSC thermograms shows that wax extracted with the hexane is more complex indicating the presence of several different compounds, compared to the waxes obtained by the other two methods. This is in agreement with the scanning electron microscope results which show less wax on the surface of hexane-treated Jatropha seeds compared to the other two solvents. The exploratory biological test carried out revealed that the waxy extracts should have some biocidal property. They induced 100% mortality of stage 4 Choristoneura fumiferana larvae at a concentration of 20%.

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Vaccalluzzo, Valerio. "Exposure of honeybees (Apis mellifera L.) and other hymenoptera pollinators to different Bacillus thuringiensis based biopesticides in laboratory controlled trials." Doctoral thesis, Università di Catania, 2016. http://hdl.handle.net/10761/4081.

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Apoidea play a fundamental and strategic role in the regulation of reproductive processes of many plants, including those of agricultural interest, due to their pollination activities. In Italy, Apoidea important for agriculture include: Apis mellifera Linnaeus 1758, known eusocial species with organization into castes Osmia cornuta, Latreille 1805 and O. rufa Linnaeus 1758, two species of solitary bees that nest in gregarious form, profitable and easy to use on different crops in semi-field and open field. However, populations of many species of Apoidea are in decline, and this phenomenon seems to be also related to the increase of the use of chemicals in agricultural practices. Biopesticides are a class of natural products used in agriculture to limit the damage caused by harmful organisms and include commercial formulations. They should be less harmful for the environment compared to traditional chemical pesticides, because they are effective at very low concentrations and have a rapid inactivation; furthermore, these products have a lower risk of non-specificity, acting mainly on the larval stages of some species of pests. Bacillus thuringiensis-based biopesticides are often used in IPM and they are dispersed in the environment. Bacillus thuringiensis (Bt) B. is one of the most common microorganisms which toxicity is due to the production of parasporal crystals exhibiting a highly specific insecticidal activity during sporulation of the bacterium. These toxic crystals (Cry), consist of different protein families (insecticidal crystal proteins or ICPs) not closely related, that are released into the environment and, once arrived in the gut of the organism by via trophic, act specifically on the epithelium of the midgut. Since insects epithelial cells of midgut are involved in multiple processes such as digestion, absorption, formation of peritrophic membrane, the alteration caused by the toxins of Bt would involve a functional impairment that could end with the death of the insect, according to the mechanisms of action. However, the natural compounds are not necessarily safer than synthetic ones because their biological properties and activity are in function of the structure rather than the origin, the applied dose in certain situations, and in relation to the safety of the product utilization. Bt-based products are considered harmless for species of Apoidea so far investigated, but it is believed that they could lead to sublethal effects, thus reducing pollinator populations in the field. Despite the importance of information on this issue, investigations, are still limited. Given the crucial role played by both honeybees and solitary bees, not only for an ecological standpoint, but also for an agro-economic aspect, I thought it was interesting to undertake investigations leading to evaluation the toxic effects associated with the administration of various concentrations of three Bt-based formulations. For this purpose, I have focused my research on the effects of products at different levels: assessing the mortality of O. cornuta, O. rufa and A. mellifera, and, for the latter species, it was observed a possible behavior modification related to histological and ultrastructural impairment of the midgut epithelium of workers. Moreover, any biochemical alteration and gene expression was assessed in midgut of workers after ingestion of one of biopesticides tested. Overall, results confirm such low toxicity of the tested Bt-based biopesticides on workers of A. mellifera and O. cornuta and O.rufa, at the concentrations presumably found in field-environment conditions, confirming that the biopesticides represent a category of commercial products certainly more convenient for the environment and the human health than the other agrochemicals, although any possible long-term and chronic effects should be taking into account.

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ELOH, KODJO. "Exploration of New Oxidative Stress Nematicidal Compounds and Valorization of Satureja montana L. Essential Oils and Hydrolates as Plant Biopesticides." Doctoral thesis, Università degli Studi di Cagliari, 2019. http://hdl.handle.net/11584/260403.

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Plant diseases cause economic challenges because they are responsible for estimated pre- and postharvest losses of 16–28% of crops yearly. Control is aimed at the use of chemical protectants, which reduce or retard the growth of the pathogen population. Another option is the use of resistant varieties, which reduce the pest population or increase recovery from injury caused by the enemies. However, resistant varieties become susceptible after few years of cultivation due to pathogen adaptation and evolution to cultivated varieties. Research of new environmentally benign products active against pests and diseases are required that control target organisms without harming the environment. In this thesis, I evaluated for the first time the nematicidal activity of new synthesized maleimide derivatives by structure-activity relationship (SAR), some selected haloacetophenones and transition metal ions. I also developed a new method to assess the metabolome alteration induced by these products on nematodes. Finally, I valorized a carvacrol chemotype domesticated plant of S. montana by evaluating its activity on insects, Spodoptera littoralis, Myzus persicae and Rhopalosiphum padi; and on the root-knot nematode Meloidogyne javanica. The maleimide derivatives were easily synthesized in a one pot reaction; haloacetophenones were commercially available and metal ions present as sulphate or nitrate salts. The tested compounds showed strong nematicidal activity against Meloidogyne incognita, X. index and G. pallida with EC50 values lower than 5 mg/L. I also found a synergism action between maleimide and copper ion on one hand and between copper ions and tannins on the other hand. A GC-MS metabolomics analysis showed that these compounds might induce oxidative stress in nematodes by modifying the levels of fatty acids and acylglycerols. After a field experiment and phytotoxicity assays, these first reported nematicidal compounds could be used in crop protection against nematodes. S. montana essential oil (EO) chemical composition was influenced by the fertilizers applied and the EO extraction method. Hence, the conventional agriculture plants showed a lower level of p-cymene with a higher level of carvacrol while more than 20 compounds showed significantly difference levels according to the method of extraction, laboratory or semiindustrial. The EOs and the organic phase of hydrolates with LC50 values of 20-65 µg/cm2 modified the feeding behavior of Spodoptera. littoralis. S. montana EOs repel Rhopalosiphon. padi and Myzus. persicae with settlement inhibition LC50 values estimated at 25-60 µg/cm2. The plant also inhibited the germination and growth of Lolium perenne at 10 mg/mL. Furthermore, ethanol extracts of S. montana did not show any activity on the pests. However, we successfully valorized the EO by product hydrolates on the insects and nematode.

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Hernowa, Kukuh. "Integrating inundative egg parasitoid release with the application of biopesticides: behavioural and developmental responses of trichogramma pretiosum (Hymenoptera : Trichogrammatidae) to neen." St. Lucia, Qld, 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17949.pdf.

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PONCET, SANDRINE. "Etude et amelioration des proprietes biopesticides de bacteries entomopathogenes, utilisees comme moyen de lutte contre les dipteres vecteurs de maladies tropicales." Paris 7, 1994. http://www.theses.fr/1994PA077284.

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Le nombre croissant d'insectes resistants aux insecticides chimiques a contribue a l'emergence de la lutte microbiologique. Bacillus thuringiensis israelensis (bti) et bacillus sphaericus (bsp), qui synthetisent pendant la sporulation des inclusions proteiques toxiques pour les larves de dipteres vecteurs de maladies tropicales, sont deja utilisees. Le travail presente dans ce memoire comporte trois themes: l'etude de l'activite des toxines de bti sur les larves de moustiques, la regulation des genes codant pour ces toxines et l'amelioration des potentialites insecticides de bti et de bsp. L'etude de la toxicite des produits des genescryiva, cryivb et cryivd, codant pour trois des polypeptides majeurs du cristal de bti montre que: a) chaque toxine forme des inclusions chez bti ; b) chacune de ces toxines possede une specificite et un niveau d'activite differents ; c) l'activite elevee du cristal est due a des interactions synergiques ou additives entre les differentes toxines. Afin d'ameliorer les potentialites insecticides de ces souches, les toxines de bti ont ete exprimees chez bsp. L'introduction chez bsp de genes de toxines de bti permet d'elargir son spectre d'activite. Une approche basee sur la recombinaison homologue a permis d'integrer le gene cryivd dans le chromosome de bsp, et l'expression conjointe des toxines de bsp et de bti semble aboutir a un phenomene de synergie. Enfin, la regulation de l'operon cryivd a ete etudiee et un gene codant pour une proteine qui pourrait agir comme chaperon a ete mise en evidence chez bti. Ces resultats suggerent qu'il est possible de definir des combinaisons de toxines presentant une toxicite optimale vis-a-vis d'un insecte cible particulier. En outre, l'utilisation de chaperons pourrait permettre d'augmenter la stabilite et/ou le taux de synthese des toxines de bti dans des hotes homologues ou heterologues

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Mechan, Llontop Marco Enrique. "Identification, Characterization, and Use of Precipitation-borne and Plant-associated Bacteria." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/96402.

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Bacteria are ubiquitously present in every ecosystem on earth. While bacterial communities that reside in specific habitats, called the microbiota, have characteristic compositions, their constituents are exchanged between habitats. To understand the assembly processes and function of a microbial community in an ecosystem, it is thus important to identify its putative sources and sinks. The sources and sinks of the plant leaf microbiome, also called the phyllosphere microbiome, are still under debate. Here, I hypothesized that precipitation is a so far neglected source of the phyllosphere microbiome. Using 16S rRNA amplicon and metagenomic sequencing, I identified the genera Massilia, Sphingomonas, Methylobacterium, Pseudomonas, Acidiphilium, and Pantoea as members of the core rain microbiome in Blacksburg, VA. Further, I used rainwater as a bacterial inoculum to treat tomato plants. I showed that rain-borne bacteria of the genera Chryseobacterium, Enterobacter, Pantoea, Paenibacillus, Duganella, Streptomyces, Massilia, Shinella, Janthinobacterium, Erwinia, and Hyphomicrobium were significantly more abundant in the tomato phyllosphere 7 days post-inoculation, suggesting that these rain-borne bacteria successfully colonized the tomato phyllosphere and had a direct impact on the composition of its microbiome. These results were confirmed by comparing the phyllosphere microbiota of tomato plants grown under greenhouse conditions, and thus never exposed to rain, compared to plants grown outside under environmental conditions, including precipitation. Since a large diversity of bacteria is associated with rain, I also hypothesized that rain-borne bacteria are well adapted to environmental stresses, similar to the stressors microbial biopesticides are exposed to in the field. I thus explored rain as a source of resilient biopesticides to control fire blight, caused by the bacterial pathogen Erwinia amylovora, on apple. In an in-vitro dual culture assay, I identified rain-borne isolates displaying broad-range inhibition against E. amylovora and several other plant pathogens. Two rain-borne isolates, identified as Pantoea agglomerans and P. ananatis, showed the strongest inhibition of E. amylovora. Further experiments showed that these two Pantoea isolates survive under environmental conditions and have a strong protective effect against E. amylovora. However, protection from disease in an orchard was inconsistent, suggesting that the timing of application and formulations must be improved for field applications. Using a UV-mutagenesis screen and whole-genome sequencing, I found that a phenazine antibiotic produced by the P. agglomerans isolate was the likely active molecule that inhibited E. amylovora. Bacterial communities are constantly released as aerosols into the atmosphere from plant, soil, and aquatic sources. When in the atmosphere, bacteria may play crucial roles in geochemical processes, including the formation of precipitation. To understand the potential role of decaying vegetation as a source of atmospheric Ice Nucleation Particles (INPs), I analyzed a historic leaf litter sample collected in 1970 that had maintained Ice Nucleation Activity (INA) for 48 years. A culture-dependent analysis identified the bacterial species Pantoea ananatis and the fungal species Mortierella alpina to have INA and to be present in the leaf litter sample. Further, I determined that both P. ananatis and M. alpina produced heat-sensitive sub-micron INPs that may contribute to atmospheric INPs. The development of new sequencing technologies has facilitated our understanding of microbial community composition, assembly, and function. Most research in bacterial community composition is based on the sequencing of a single region of the 16S rRNA gene. Here, I tested the potential of culture-independent 16S rRNA sequencing of the phyllosphere microbiome for disease diagnosis. I compared the community composition of the microbiome of the aerial parts of cheddar pinks (Dianthus gratianopolitanus) that showed disease symptoms with the microbiome of healthy plants to identify the causative agent. However, I found that the pathogen is probably ubiquitous on cheddar pinks since it was present at similar abundance levels in symptomatic as well as healthy plants. Moreover, the low-resolution of 16S rRNA sequencing did not allow to identify the pathogen at the species or strain level. In summary, in this thesis, I found support for the hypothesis that rain is one of the sources of the phyllosphere microbiome, that rain is a promising source of biopesticides to control plant diseases in the field, that leaf litter is a source of atmospheric INPs, and that 16S rRNA sequencing is not well suited for pathogen identification in support of plant disease diagnosis. Finally, in additional research to which I contributed but that is not included in this thesis, I found that metagenomic sequencing can identify pathogens at the species and strain level and can overcome the limitations of 16S rRNA sequencing.
Doctor of Philosophy
Bacteria are present in nearly every ecosystem on earth. Bacterial communities that reside in a specific habitat are known as microbiota and have characteristic compositions and functions that directly impact the health of ecosystems. Microbiota associated with plants, the so-called plant microbiota, play a crucial role in plant fitness. Thus, it is important to study the assembly and diversity of plant microbiota and their impact on the ecosystem. The sources of leaf microbiota remain to be elucidated. Here, I have studied the contribution of rainfall to the bacteria that live on and in plant leaves. First, using DNA sequencing, I identified the bacteria present in rainfall in Blacksburg, VA. Then, using rain as bacterial inoculum, I found that some rain-borne bacteria, including members of the genera Pantoea, Massilia, Janthinobacterium, and Enterobacter, are efficient colonizers of tomato leaves. Either absence or low abundance of rain-borne bacteria from tomato leaves never exposed to rainfall confirmed further that bacteria in rain contribute to the assembly of plant leaf microbiota. The identification of all putative sources and sinks of leaf microbiota is important when trying to manipulate them to improve plant health and crop yield. Since I found that rainfall contains many different bacteria, I also studied the potential application of rain-borne bacteria in agriculture. The main limitations of commercial bio-pesticides are their poor survival and limited efficacy in the field. Here, I speculated that rain-borne bacteria are well adapted to environmental stressors and could represent efficient bio-pesticides under field conditions. In fact, I isolated two rain-borne bacteria from the genus Pantoea that strongly inhibited Erwinia amylovora, the causal agent of the fire blight disease of apple, in the laboratory under controlled conditions. However, I observed inconsistent results in a 2-year field trial in an orchard. Using mutagenesis and DNA sequencing, I found the active molecule that likely inhibited E. amylovora, in one of the rain-borne isolates. Finally, the access to newer and cheaper sequencing technologies has recently facilitated the study of bacteria at large scale. Most research of microbiota is based on the sequencing of a single region of one gene, the 16S rRNA gene. Here, I tested the potential of 16S rRNA sequencing of leaf microbiota for disease diagnosis. However, I identified the pathogen in healthy and diseased plants, suggesting its ubiquitous presence. Further, due to the low-resolution of 16S rRNA sequencing, it was impossible to identify the pathogen at the species level. In summary, I found that rain is a source that contributes to leaf microbiota, that rain is a promising source of bio-pesticides to control plant diseases, and that 16S rRNA sequencing is not recommended as a tool to diagnose plant diseases.

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Lakhdar, Fatima. "Contribution à l'étude des potentialités antiproliférative et antibactérienne des algues brunes et rouges de la côte d'El Jadida pour une valorisation médicale et environnementale." Thesis, Nantes, 2018. http://www.theses.fr/2018NANT4037/document.

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L’objet de ce travail se focalise sur la recherche et la caractérisation de composés bioactifs issus d’algues de la côte marocaine. Ceci peuvent être utilisés soit en pharmacologie ou bien en phytopathologie. Le premier volet est consacré à l’étude des potentialités nutritionnelle et pharmacologiques de 6 espèces d’algues marines, parmi 24, les plus riches en lipides. La recherche des fractions actives en utilisant différentes méthodes de purification et d’essais bioguidés, ont montré une importante activité antiproliférative contre les cellules humaines du cancer du poumon (NSCLC-N6 et A549) avec une CI50<13 g/mL. Ces fractions, contenant des monogalactosyldiacylglycerol font l’objet d’élucidation du point vue structural (RMN et Masse haute résolution) plus poussées. Le deuxième volet est consacré à la valorisation des algues marines en phytopathologie. L’étude de l’activité antibactérienne a permis de déterminer in vitro et in vivo l’effet bio-pesticide des extraits d’algues rouges et brunes récoltées contre la pourriture molle de la pomme de terre causée par Dickeya dadantii. Leur utilisation directe sur des plantes de pomme de terre infectées par Dickeya dadantii comme biostimulant montre une élimination nette des symptômes de la pourriture molle et une amélioration de la croissance chez les plantes traitées. Ces derniers semblent ainsi intervenir en accélérant et en intensifiant l’enrichissement des plantes en enzymes impliquées dans la cascade de signalisation afin de stimuler les mécanismes de défenses. L’élicitation par les extraits d’algues semble donc intervenir en renforçant les mécanismes de défense des plantes de la pomme de terre contre Dickeya dadantii
Either in pharmacology or in phytopathology. The first f 6 species of pharmacological potentialities o part is devoted to the study of the nutritional and coast. This can be used The purpose of this work focuses on the research and characterization of bioactive compounds from algae of the Moroccan seaweed, among 24 , the richest in lipids. The search for active fractions usi ng different purification methods and bioguide tests, showed a significant anticancer activity against human lung cancer cells (NSCLC - N6 and A549) with an IC 50 <13 g/ mL. These monogalactosyl diacylglycerol containing fractions are further elucidated structurally (NMR and high mass resolution ). The second part is dedicated to the valorisation of seaweed in phytopathology. The study of the antibacterial activity made it possible to determine in vitro and in vivo the bio - pesticidal effect of extracts of red and brown algae harvested against the soft rot of the potato caused by Dickeya dadantii . Their direct use on potato plants infected with Dickeya dadantii as a biostimulant shows clear elimination of sympto ms of soft rot and improved growth in treated plants. The latter seem to intervene by accelerating and intensifying the enrichment of plants in enzymes involved in the signaling cascade in order to stimulate the defense mechanisms. Elicitation by algae ext racts seems to intervene by strengthening the defense mechanisms of potato plants against Dickeya dadantii

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Macedo, Leonardo Lima Pepino de. "Atividade bioinseticida e mecanismo de a??o de vicilinas de sementes Erythrina velutina sobre moscas-das frutas Ceratitis capitata." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12536.

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The fruit fly Ceratitis capitata is considered the most destructive pest of the world fruitculture. Many pest management practices, mainly based on agrochemicals, have been developed to allow the world-wide commerce of fruit. Solutions to decrease the use of synthetic insecticides in agriculture are based on the development of new target-specific compounds which cause less damage to the environment, especially vegetal proteins with insecticidal effects. The aim of this work was to evaluate the deleterious effect of a purified vicilin of E. velutina (EvV) seeds to C. capitata larvae and adult insects and to investigate the mechanisms involved in these effects. EvV was purified, characterized and its deleterious effect was tested in bioassay systems. EvV mechanism of action was determined by immunodetection techniques and fluorescence localization in chitin structures that are present in C. capitata digestory system. EvV is a glycoprotein with affinity to chitin. Its molecular weight, of 216,57 kDa, was determined by gel filtration chromatography in FPLC system. Using SDS-PAGE, it was possible to observe EvV dissociation in two main subunits of 54,8 and 50,8 kDa. When it was submitted to eletrophoresis in native conditions, EvV presented only one band of acid characteristic. The WD50 and LD50 values found in the bioassays were 0,13% and 0,14% (w/w), respectively for the larvae. EvV deleterious effects were related to the binding to chitin structures presented in peritrophic membrane and gut epithelial cells, associated with its low digestibility in C. capitata digestive tract. The results described herein are the first demonstration of the larvicidal effects of plant protein on C. capitata larvae. EvV may be part of the pest management programs, in the toxic bait composition, or an alternative in plant improvement program
A mosca-da-fruta Ceratitis capitata ? considerada a praga mais destrutiva da fruticultura mundial, para o seu controle v?rios programas de erradica??o baseados em agroqu?micos foram criados para permitir o com?rcio mundial de frutas. Solu??es para a diminui??o do uso de inseticidas sint?ticos na agricultura est?o baseadas no desenvolvimento de novos compostos alvos-espec?ficos com menos persist?ncia no meio ambiente, em especial prote?nas vegetais com efeitos inseticidas. Neste trabalho o principal objetivo foi avaliar o efeito delet?rio de uma vicilina purificada de sementes de E. velutina (EvV) para larvas de C. capitata e propor o mecanismo de a??o da prote?na. EvV foi purificada, caracterizada e o seu efeito delet?rio foi testado em sistemas de bioensaios. O mecanismo de a??o de EvV foi determinado por t?cnicas de imunodetec??o e localiza??o por fluoresc?ncia em estruturas quitinosas, presentes no sistema digest?rio de C. capitata. EvV ? uma glicoprote?na com afinidade a quitina cuja massa molecular foi de 216,57 kDa, determinado por cromatografia de gel filtra??o em sistema de FPLC. Por SDS-PAGE, EvV dissociouse em duas subunidades principais de 54,8 e 50,8 kDa, e quando foi submetida a eletroforese em condi??es nativas apresentou uma banda ?nica de caracter?stica eletrofor?tica ?cida. Nos bioensaios a WD50 e a LD50 para as larvas foram de 0,13% e 0,14% (p/p). Os efeitos delet?rios de EvV foram relacionados a sua liga??o a estruturas quitinosas presentes na membrana peritr?fica e no epit?lio intestinal, associado com a baixa capacidade de C. capitata em digeri-la. Com esses resultados ? poss?vel propor a EvV como candidata a fazer parte de programas de manejo integrado de pragas, na composi??o de iscas t?xicas, como um potencial bioinseticida de natureza prot?ica.

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Cepeda, Maria Veronica. "Effects of Microbial Inoculants on Biocontrol and Plant Growth Promotion." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1345239027.

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Rahbani, Jihane. "Optimisation, étude de la cinétique et dimensionnement de la production des biopesticides à base de souches de Bacillus thuringiensis isolées du sol Libanais." Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/13815/1/Rahbani.pdf.

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Parmi les méthodes alternatives respectueuses de l'environnement pour la lutte contre les ravageurs et la protection des cultures agricoles, les bioinsecticides à base de Bacillus thuringiensis sont les plus largement utilisés. L’activité insecticide de B.thuringiensis réside dans la production d’inclusions cristallines protéiques appelées δ-endotoxines qui sont formées au cours de la sporulation. En préalable à ces travaux, de nouvelles souches de B.thuringiensis ont été isolées du sol libanais et ont montré un potentiel insecticide élevé, supérieur à des souches classiquement utilisées. Dans le cadre du développement d'une production industrielle, au Liban, de biopesticides à base de ces souches de B.thuringiensis, ce travail a visé à optimiser la production des δ-endotoxines afin d'augmenter les rendements et de réduire les coûts de production. A l'échelle industrielle, le milieu de culture des bactéries représente une part importante du coût de production. Ainsi, l'effet, sur la concentration des δ-endotoxines, de substitution des sources synthétiques coûteuses d'azote, de carbone et de minéraux, par un sous-produit de la minoterie de blé (le son de blé) a été étudié. L’efficacité de ce sous-produit agro-industriel comme source complète de nutriments, disponible localement à faible prix, a été prouvée pour des fermentations submergées de deux souches différentes toxiques contre des diptères ou des lépidoptères. La comparaison du milieu son de blé à d’autres milieux (synthétiques ou non), classiquement utilisés en bibliographie, a montré que ce milieu présente de nombreux avantages en termes de productivité, de rendement relatif des δ-endotoxines et de coût. Parallèlement à ce travail, une méthode simple et rapide de purification des cristaux a été développée de façon à obtenir des cristaux protéiques purs à 99 % nécessaires comme standards pour le dosage des cristaux dans le milieu de fermentation. Un autre objectif du travail a été d’analyser l'effet de l'aération sur la cinétique de croissance et de sporulation d'une nouvelle souche de B.thuringiensis var kurstaki. Les différentes conditions d’aération testées en fermenteurs de 2 L, caractérisées par le coefficient volumétrique de transfert de dioxygène (KLa), ont permis de montrer l’importance de ce paramètre et de l’optimiser pour obtenir la meilleure productivité en biopesticides. Le meilleur rendement en protéines de toxines a été obtenu dans un milieu son de blé 6 % (masse/volume) dans des conditions d’aération correspondant à un KLa de 65,5 h-1 alors que la meilleure productivité des protéines de toxines a été atteinte dans le milieu 9 % pour un KLa de 102 h-1. Sur la base de cette étude, le dimensionnement de la production de B.thuringiensis à l’échelle 1000 L a été réalisé. L’unité de production a été construite et les premiers essais réalisés ont permis de produire de façon satisfaisante des lots de biopesticides. L’ajustement des protocoles industriels reste à faire.

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Scudeler, Elton Luiz. "Avaliação da capacidade de renovação do epitélio do mesêntero e seus efeitos no potencial reprodutivo de fêmeas adultas de Ceraeochrysa claveri (Neuroptera Chrysopidae) alimentadas durante a fase larval com óleo de nim (azadirachta indica A. JUSS) /." Botucatu, 2016. http://hdl.handle.net/11449/137933.

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Orientador: Daniela Carvalho dos Santos
Resumo: Devido ao uso indiscriminado de inseticidas de largo espectro na produção agrícola e a vulnerabilidade dos inimigos naturais a este tipo de exposição, efeitos colaterais podem afetar a função biológica destes inimigos, tornando sua utilização no controle biológico impraticáveis. A busca por pesticidas mais seletivos sobre esses organismos benéficos é necessária, e entre as alternativas, enfatizamos o aumento do uso dos biopesticidas. Um dos biopesticidas amplamente utilizados é o óleo de nim (Azadirachta indica), e sua segurança e compatibilidade com os inimigos naturais têm sido mais esclarecidos através de estudos ecotoxicológicos que verificam os efeitos da exposição indireta através da ingestão de presas contaminadas. Assim, este estudo analisou a resposta das células epiteliais do mesêntero de adultos do crisopídeo Ceraeochrysa claveri quando expostos por ingestão de presa contaminada com óleo de nim durante a fase larval e a ocorrência de efeitos letais e subletais em seu desenvolvimento. Larvas de C. claveri foram alimentadas com ovos de Diatraea saccharalis tratados com óleo de nim nas concentrações de 0,5%, 1% e 2% durante todo período larval. Fêmeas adultas obtidas a partir destes tratamentos foram utilizadas em análises morfológicas e ultraestruturais da resposta celular do mesêntero. Além disso, parâmetros biológicos também foram avaliados durante o desenvolvimento pós-embrionário. O óleo de nim provoca efeitos citotóxicos no mesêntero através de pronunciadas alte... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Due to the indiscriminate use of broad-spectrum insecticides in agricultural production and the vulnerability of natural enemies to this type of pesticide exposure, side effects can affect the biological function of these enemies, making their use for biological control unfeasible. A search for more selective pesticides on these beneficial organisms is necessary, and among the alternatives, we emphasize the increased use of biopesticides. One of the biopesticides widely used is the neem oil (Azadirachta indica), and its safety and compatibility with natural enemies have been more clarified through ecotoxicological studies which check the effects of indirect exposure by intake of poisoned preys. Thus, this study analyzed the response of midgut epithelial cells of adult of lacewing Ceraeochrysa claveri when exposed by intake of contaminated prey with neem oil during the larval stage and the occurrence of lethal and sublethal effects on its development. Larvae of C. claveri were fed on eggs of Diatraea saccharalis treated with neem oil at a concentration of 0.5%, 1% and 2% throughout the larval stage. Adults female obtained from these treatments were used in the morphological and ultrastructural analyses of cellular response of midgut. Moreover, biological parameters were also measured during the post embryonic development. Neem oil causes cytotoxic effects on the midgut through pronounced alterations as cell swollen, loss of integrity of cell cortex, dilated cisternae of the ro... (Complete abstract click electronic access below)
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Thaler, Jacques-Olivier. "Bases biologiques et biochimiques des barrières microbiennes impliquées dans la monoxénie et la spécificité des symbioses bactério-helminthiques." Montpellier 2, 1995. http://www.theses.fr/1995MON20055.

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Le travail de these porte sur les relations ecologiques entre l'helminthe entomophage, steinernema carpocapsae, et sa bacterie associee, xenorhabdus nematophilus. Cette etude est un prealable indispensable a une utilisation raisonnee des nematodes entomopathogenes comme biopesticides. Les resultats obtenus posent les bases biologiques et biochimiques qui permettent d'expliquer d'une part, les phenomenes de competition inter-organismes multiples qui se produisent dans l'insecte parasite et, d'autre part, le maintien de l'association entre le nematode et son symbionte. Trois antibiotiques ont ete mis en evidence. Le premier a ete identifie comme correspondant aux xenocoumacines. Le second est probablement un peptide apparente au groupe des microcines. Le troisieme est une bacteriocine de type queue de phage dont la purification et la caracterisation ont permis de l'identifier comme un nouveau compose: la xenorhabdicine. Cette these a permis d'apporter les bases necessaires a l'identification des genes de synthese des bacteriocines et de mieux comprendre leur role ecologique

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Avila, Renata Couto. "Resist?ncia clonal ? Thaumastocoris peregrinus e caracteriza??o qu?mica por CG/EM de ?leo essencial de eucalipto." UFVJM, 2016. http://acervo.ufvjm.edu.br/jspui/handle/1/1344.

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Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)
Por causa da introdu??o de pragas ex?ticas, as planta??es de Eucalipto est?o sofrendo com consider?veis perdas na produ??o por todo o territ?rio brasileiro. Uma dessas pragas foi detectada em 2008 e ? conhecida como percevejo bronzeado (Thaumastocoris peregrinus). Essa praga de origem Australiana se espalhou rapidamente pelas planta??es de eucalipto no pa?s por causa da falta de seu inimigo natural. Ainda n?o foi encontrado um controle eficaz para o percevejo bronzeado. Para se conseguir a certifica??o florestal, n?o ? recomendado o uso de inseticidas qu?micos ou sint?ticos. Uma das alternativas para o controle desse inseto ? a detec??o e utiliza??o de gen?tipos resistentes nas planta??es e a utiliza??o de bioinseticidas a partir de ?leos essenciais. Para essa constata??o se faz necess?rio testes de resist?ncia nos gen?tipos a fim de encontrar as ideais para os plantios. No laborat?rio de Biotecnologia Florestal da UFVJM foi realizado teste de sobreviv?ncia e de n?o-preferencia alimentar em 27 clones comerciais da empresa Gerdau LTDA e de indiv?duos de Eucalyptus camaldulensis e Corymbia. citriodora, a fim de identificar o n?vel de resist?ncia e suscetibilidade entre os mesmos. Para as duas vari?veis foram considerados os gen?tipos C. citriodora e os clones C4, C11, C24, C25, C27 e C17 como sendo altamente suscept?veis em rela??o aos demais, e os clones C1, C15, C20, C21 e C13 como sendo os mais resistentes em rela??o aos demais. Ap?s a caracteriza??o dos clones foram extra?dos os ?leos essenciais de 3 clones resistentes, 3 suscept?veis e de indiv?duos de E. camaldulensis. Nos ?leos extra?dos foram encontrados compostos que s?o descritos para o controle de diversos insetos, como 1,8 cineol e linalool. Esses compostos comprovam o potencial inseticida dos ?leos essenciais de eucalipto.
Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016.
Because of the introduction of exotic pests, these plantations are suffering considerable losses in production throughout the Brazilian territory. One such pest was detected in 2008 and is known as Bronze bug. This Australian origin worm spread rapidly through the Eucalyptus plantations in the country because of the lack of their natural enemy. We have not yet found an effective control for Bronze bug. To achieve forest certification is not recommended the use of chemical insecticides. One of the alternatives to control this insect is the detection and use of resistant genotypes in plantations and the use of biopesticides from essential oils. For this finding is necessary stress tests in genotypes in order to find the ideal for plantations. In laboratory UFVJM Forest Biotechnology was held survival test and non-food preference in 27 commercial clones of Gerdau LTDA and E. camaldulensis individuals and C. citriodora in order to identify the level of resistance and susceptibility among thereof. For the two variables were considered the genotypes E. Citriodora, C4, C11, C24, C25, C27 and C17 as the most susceptible in relation to others and the clones C1, C15, C20, C21 e C13 as the toughest in relation to others After the characterization of the clones, have been derived the essential oils of three resistant clones, three susceptible clones and E. camaldulensis. In extracted oils, it have been found many compounds that are described to control various insects, as 1,8 cineol and linalool. These compounds show potential insecticide essential oils of Eucalyptus.

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NTALLI, NIKOLETTA. "Phytochemistry in the development of pesticides and biocides." Doctoral thesis, Università degli Studi di Cagliari, 2016. http://hdl.handle.net/11584/266867.

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To date biopesticides and biocides are studied as substitutes for their toxic synthetic ancestors. The botanical pesticides are evaluated as tools intended for integrated crop protection schemes, while the natural biocides for their potential use in residential areas. In this study we evaluate various botanical matrixes for the nematicidal properties against the root knot nematode Meloidogyne spp., in the form of pastes and extracts for soil amendment as well as plant secondary metabolites isolated from the afore mentioned matrixes and used individually or in binary mixtures to create synergism. The effects of the treatment compound/s are evaluated in various growth stages of the parasite, considering physiology and behavior. Additionally we investigate the use of botanical extracts as natural biocides for the control of toxic cyanobacteria Aphanizomenon gracile in fresh waters. A first attempt is made to formulate a natural algicidal compound into a slow release product that could permit a long lasting biological activity and thus higher efficacy under open air conditions

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Parmentier, Cajaiba Aura. "La construction de compétences fondamentales : une application à l'homologation dans l'industrie du biocontrôle." Grenoble, 2010. http://www.theses.fr/2010GRENG016.

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Ce travail de thèse repose sur une étude de cas de l'homologation de produits dans deux entreprises du secteur phytosanitaire et sur la littérature académique relative aux approches par les ressources et par les compétences (Barney l99l, Freiling Gersh Goeke 2008, Ljungquist 2008. Prahalad et Hamel, l990). La problématique de construction d'une compétence fondamentale éloignée du cœur de métier pour des PME en situation de ressources limitées est divisée en deux thématiques : le contenu de la compétence et le processus associé. Cette recherche constructiviste (Avenier 2010) est un exemple du travail de légitimation possible dans ces paradigmes épistémologiques. L'interprétation du matériau empirique répond à deux questions relatives au contenu et au processus de construction d'une compétence. Ce matériau a été synthétisé par la mise en œuvre d'un outil méthodologique central : la cartographie du journal de recherche. Il est inspiré des travaux de Langley (I999). Les étapes de codages successives permettent de donner une réponse en terme de contenu. L'interprétation des codes mène a une compréhension originale des processus. Les apports théoriques s'expriment par la proposition de la notion de compétence fondamentale réglementaire, celle de valeur réglementaire et d'une compréhension fine des mécanismes entre ressources, capacités et compétences. Les apports méthodologiques sont la proposition d'un outil méthodologique réflectif et de voies d'opérationalisation des critères de légitimation des savoirs en épistémologies constructivistes. Enfin les apports managériaux consistent en une base pour l'action dédiée à des entreprises contraintes par des milieux règlementés
This doctoral work deals with competence creation. A two-firm case study about product registration shows an organizational-competence creation in context. It is an operationalization of the competence-based perspective model (Freiling Gersch Gocke, 2008) associated to typologies of resources and competencies stemming from both RBV (Barney l99l, Peteraf, I993) and the Competence literature (Prahalad et Hamel, l990; Ljungquist 2007, 2008). The two research questions aim at understanding what a competence is made of and how its elements are organized. Data used was synthesized through an organizational flowchart. This tool based on the work of Langley (l999) helps stepping back from the field and helps researchers to be more reflective. Successive data coding lead to understanding the content of a competence through a thematic flowchart. Following this tirst step, l implemented interpretive studies of these codes to propose a consistent articulation of the competence elements previously proposed. Theoretical contribution appears through the content / process perspective adopted. L also proposed a detail understanding of how resources, capabilities and competencies are intertwined. I eventually propose two theoretical notions: the regulatory core competence and the regulatory value. The methodological contribution of this research shows how knowledge in constructivist epistemology (Avenier 2010) can be legitimized in a concrete manner. L also develop a methodological tool that helps researchers carrying out research in natural setting. L finally proposed a base for practitioner to implement a competence in highly regulated environment

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Santos, Daiane Rodrigues dos. "Atividade inseticida de extratos e ?leos essenciais de esp?cies do G?nero Lippia contra Callosobruchus maculatus (Fabricius, 1775) e Nasutitermes corniger (Motschulsky, 1855)." Universidade Estadual de Feira de Santana, 2017. http://localhost:8080/tede/handle/tede/503.

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The exploitation potential of new biopesticides sources is very broad in Brazil and worldwide. In the past few years, the search for these products has been intensified due to serious health and environmental issues caused by the use of synthetic insecticides. In this context, essential oils and extracts of vegetal species have been considered as an alternative to agriculture. Thus, the aim of this work was to test the insecticidal potential of species belonging to the genus Lippia Lippia insignis Mondenk 1976, Lippia lasiocalycina Schauer, 1832 e Lippia thymoides Martius & Schauer, 1832 no controle de insetos-praga que provocam danos econ?micos (Callosobruchus maculatus Fabricius, 1775 e Nasutitermes corniger Motschulsky, 1855) in the control of insect-pest responsible for economic damage (Callosobruchus. maculatus and Nasutitermes corniger). The samples were collected in the experimental area in the Horto Florestal (UEFS) and after the material was dried, the essential oils were extracted and the extracts were prepared. In vitro trials were performed in order to verify the effects of essential oils and extracts against C. maculatus and N. corniger. The methodology of exposition to contaminated surface, testing an initial concentration of aqueous and methanolic extract and essential oils was adopted to determine the insecticidal activity of extracts and oils. The mortality was verified 24 and 48 hours after treatment application, and the product with major potential on the insect mortality was diluted in different concentrations to determine the medium lethal concentration (LC50). The repellent activity against C. maculatus and N. corniger was evaluated. Moreover, specific tests with C. maculatus investigated the product efficiency in two methods of application, as well as the quantification and identification of chemical constituents present in the studied species oils using GC/FID and GC/MS techniques. The results obtained revealed, occurrence highlighted of ?-mirceno and E -ocimenona in the sample of L. lasiocalycina, in L. insignis were prominent ?-mirceno e o limoneno. For L. thymoides the main constituents were: E-cariofileno e o ?xido de cariofileno.for C. maculatus, the essential oil of L. insignis stood out as insecticidal activity with CL50 of 3,11 ?l/ml. Although both methods of application showed efficiency in the control of this insect-pest, there was no repellent activity verified in the oil of L. insignis (5?l/ml). For N. corniger, the essential oils of all tested species, as well as the methanolic extract of L. insignis exhibited promising results in the control of this insect-pest. It was also verified that L. lasiocalycina possessed lower LC50 (0,47 ?l/ml) compared to L. insignis (0,88 ?l/ml) and L. thymoides (3,64 ?l/ml), while the LC50 of L. insignis methanolic extract was 27,84 mg/ml. Furthermore, essential oils and methanolic extracts of Lippia studied species revealed repellent activity in the N. corniger in vitro trials.
O potencial de explora??o de novas fontes de biopesticidas ? bastante amplo no Brasil e no mundo. Nos ?ltimos anos, a busca por esses produtos tem se intensificado em virtude dos graves problemas de sa?de e ambientais advindos do uso de inseticidas sint?ticos. Neste contexto, os ?leos essenciais e extratos de esp?cies vegetais tem se mostrado uma boa alternativa para a agricultura. Deste modo, o objetivo deste trabalho foi testar o potencial inseticida de esp?cies pertencentes ao g?nero Lippia (Lippia insignis Mondenk 1976, Lippia lasiocalycina Schauer, 1832 e Lippia thymoides Martius & Schauer, 1832 no controle de insetos-praga que provocam danos econ?micos (Callosobruchus maculatus Fabricius,1775 e Nasutitermes corniger Motschulsky, 1855). A coleta das plantas foi realizada na ?rea experimental do Horto Florestal da UEFS e o material coletado, ap?s a secagem, foi destinado a extra??o de ?leos essenciais e preparo dos extratos. Foram realizados ensaios in vitro para verifica??o dos efeitos dos ?leos essenciais e extratos contra C. maculatus e N. corniger. Para a determina??o inicial da atividade inseticida dos extratos e ?leos foi utilizada a metodologia de exposi??o ? superf?cie contaminada, testando-se uma concentra??o inicial do extrato aquoso, extrato metan?lico e ?leos essenciais. A mortalidade foi verificada 24 e 48 hs ap?s a aplica??o dos tratamentos. O produto com maior potencial sobre a mortalidade dos insetos testados foi dilu?do em diferentes concentra??es para determina??o da concentra??o letal mediana (CL50). A atividade repelente contra C. maculatus e N. corniger foi avaliada. Al?m disso, testes espec?ficos com C. maculatus investigaram a efici?ncia do produto em dois m?todos de aplica??o, bem como a quantifica??o e identifica??o de constituintes qu?micos presentes nos ?leos de esp?cies estudados utilizando t?cnicas GC/ FID e GC / MS. Os resultados demonstraram, a ocorr?ncia destacada do ?-mirceno e E-ocimenona nas amostras de L. lasiocalycina, em L. insignis destacaram-se, ?-mirceno e limoneno. Para L. thymoides os constituintes principais foram: E-cariofileno e o ?xido de cariofileno. Para C. maculatus, que o ?leo essencial da esp?cie L. insignis destacou-se quanto ? atividade inseticida com CL50 de 3,11 ?l/ml. Embora ambos os m?todos de aplica??o tenham se mostrado eficientes no controle deste inseto-praga, n?o foi verificada atividade repelente do ?leo de L. insignis (5?l/ml). Para N. corniger, os ?leos essenciais de todas as esp?cies testadas, al?m do extrato metan?lico da esp?cie L. insignis mostraram-se promissores no controle a este inseto-praga. Foi verificado que a esp?cie L. lasiocalycina apresentou menor CL50 (0,47 ?l/ml) comparada a L. insignis (0,88 ?l/ml) e L. thymoides (3,64 ?l/ml), j? o extrato metan?lico de L. insignis obteve CL50 de (27,84 mg/ml). Os ?leos essenciais e extrato metan?lico das esp?cies de Lippia estudadas demonstram atividade repelente a N. corniger nos ensaios in vitro.

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Powell, Michelle Emma. "Development of next-generation biopesticides as a control method for the small hive beetle Aethina tumida Murray (Coleoptera: Nitidulidae), a serious pest of the European honey bee Apis mellifera." Thesis, Durham University, 2019. http://etheses.dur.ac.uk/12952/.

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The small hive beetle (Aethina tumida) is a serious pest of the European honey bee (Apis mellifera), responsible for causing significant economic damage to the apiculture industry in North America and Australia. In 2014 A. tumida was detected in Italy, highlighting the potential for an outbreak within the UK. Current control measures rely on the use of organophosphate and permethrin, both are highly toxic to honeybees and continued use can give rise to resistance. Given these issues alternative control strategies are urgently required. The aims of this thesis were to explore potential for the development of next generation biopesticides, including RNA interference (RNAi) and fusion protein technology, as an alternative control method for A. tumida The sequence specificity of RNAi makes it an ideal strategy to combat this parasite of honey bees. Here we report that microinjection of low (2-10 ng) doses of V-ATPase subunit A and Laccase 2 dsRNAs resulted in 100 % mortality of A. tumida larvae. Quantitative PCR analysis confirmed that injections induced significant decreases in mRNA levels of the target genes with an enhancement of gene suppression over time providing evidence for systemic RNAi effects. Whilst oral delivery of V-ATPase subunit A dsRNA via "soaking" in dsRNA solutions resulted in 50 % mortality and malformed survivors, gene suppression could not be verified by qPCR analysis. Our results showed that dsRNAs are prone to degradation by extracellular nucleases following ingestion by feeding, but not wandering stage, larvae. We suggest that the lack of consistent RNAi effects in feeding experiments was a consequence of dsRNA degradation within the gut of A. tumida. Target specificity was confirmed by a lack of effect on survival or gene expression in honey bees injected with A. tumida dsRNAs. A. tumida show a robust response to injected dsRNA but further research is required to develop methods to induce RNAi effects via ingestion. The spider-venom peptide ω-hexatoxin-Hv1a (Hv1a) is highly potent by injection to a range of insects, but not vertebrates making it an ideal candidate for the development of bioinsecticides. Oral delivery of the toxin is largely ineffective due to failure to access its site of action in the central nervous system (CNS). Fusion protein technology allows oral delivery of Hv1a to the CNS via fusion to a "carrier" protein, snowdrop lectin Galanthus nivalis agglutinin (GNA), directing transport of the toxin across the insect gut to the circulatory system. Constructs encoding Hv1a or modified Hv1a (K > Q modification to remove potential KEX2 cleavage site) linked to the N- or C-terminus of snowdrop lectin (GNA) were used to produce recombinant GNA/Hv1a, Hv1a/GNA fusion proteins and K > Q. All four fusion proteins were toxic by injection to A. tumida. The LD50's for GNA/Hv1a and GNA/Hv1a(K > Q) were a similar 0.44 and 0.47 µg/µl, whilst Hv1a/GNA and Hv1a(K > Q)/GNA LD50's were slightly lower, at a respective 0.33 and 0.25 µg/µl. In contrast no effects on honeybee survival were observed when 20 fold higher doses were injected. When fed to A. tumida larvae, GNA/Hv1a was 2x more effective than Hv1a/GNA, GNA/Hv1a(K > Q) and Hv1a(K > Q)/GNA (LC50s of 0.52, 1.14, 1.18 and 0.89 mg/ml, respectively). When fed to A. tumida adults no mortality was recorded for GNA/Hv1a(K > Q) or Hv1a(K > Q)/GNA treatments. However, both Hv1a/GNA and GNA/Hv1a were toxic to adults, with similar LC50s of 2.52 and 2.02 mg/ml, respectively. Reduced efficacy of Hv1a/GNA and K > Q variants against larvae was shown to be attributable to differences in the stability of the fusion proteins in the presence of extracellular gut proteases. In laboratory assays A. tumida larval survival was significantly reduced when brood, inoculated with eggs, was treated with GNA/Hv1a. The dominant digestive protease in A. tumida larvae was identified as trypsin. Consequently, a trypsin inhibitor (Soybean Kunitz trypsin inhibitor: SKTI) was incubated together with A. tumida gut extracts and GNA/Hv1a and Hv1/GNA, with both fusion protein remaining fully intact after 24 hr. This contrasted with previous analysis that showed no intact GNA/Hv1a or Hv1a/GNA after incubation with gut extracts in the absence of the trypsin inhibitor under comparable conditions. Consequently, SKTI was evaluated as an alternative carrier protein to GNA for the delivery of Hv1a to the circulatory system of A tumida. Preliminary studies indicated transport of SKTI into the haemolymph, suggesting SKTI could be used as an alternative carrier protein. An initial construct was designed based on GNA/Hv1a, however no biological activity was observed after injection into A. tumida larvae. It was speculated that the lack of insecticidal activity was attributed to the misfolding of the toxin during expression in the yeast cells. As such two additional fusion proteins were designed incorporating either a flexible (Gly-Gly-Gly-Gly-Ser motif) or rigid linker (Proline rich motif region) to improve protein folding and function. Only inclusion of a rigid linker showed limited biological activity after injection into A. tumida larvae, again suggesting misfolding of the toxin. Both RNAi and fusion protein technology hold enormous potential for the control of A. tumida in apiculture and to our knowledge this is the first study to demonstrate the use of a protein based biopesticide and RNAi as a possible control method for A. tumida.

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Oliveira, Daian Guilherme Pinto de. "Proposta de um protocolo para avaliação da viabilidade de conídios de fungos entomopatogênicos e determinação da proteção ao calor conferida a Beauveria bassiana e Metarhizium anisopliae pela formulação em óleo emulsionável." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-23022010-082337/.

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Este trabalho teve o objetivo de avaliar, em condições de laboratório, a influência da temperatura e do tempo de exposição na viabilidade e virulência dos fungos Beauveria bassiana e Metarhizium anisopliae em suspensões preparadas com produtos à base de Conídios puros, Arroz+fungo e nas formulações Pó molhável e Suspensão concentrada em óleo emulsionável. Inicialmente foi necessário o desenvolvimento de um método eficiente e econômico para avaliação da viabilidade, especialmente para produtos formulados em óleo emulsionável misturados em água (suspensão de aplicação). Durante o desenvolvimento do método de avaliação foram definidos parâmetros e condições adequadas para cada formulação, como o meio de cultura, e também a influência de antibióticos e fungistáticos. O protocolo estabelecido baseiase resumidamente no plaqueamento de 150 µL de uma suspensão contendo entre 0,7 e 1×106 conídios/mL em placas tipo Rodac® com 5 mL de meio de cultura Batata-Dextrose-Ágar + 5 mg/L de Pentabiótico® e 10 µL/L de Derosal® (Carbendazim), efetuando-se posteriormente a contagem dos conídios germinados. Este método foi comparado com outra técnica de viabilidade direta (VD) e com as técnicas de Unidade Formadoras de Colônia (UFC) e viabilidade por fluorescência, confrontando-se a precisão obtida pelo coeficiente de variação (CV) das análises de cada método. Os resultados demonstraram que além da facilidade de execução, o método desenvolvido apresentou maior precisão que as demais técnicas (com CV até 7 vezes menor em relação à VD, e até 32 vezes menor que UFC). Foi constatado que a técnica de UFC não é adequada para avaliações de produtos formulados, visto que em relação à quantificação inicial subestimou a concentração viável na maioria das formas dos fungos testadas, sendo que nos produtos em óleo emulsionável estes valores foram 54% menores para B. bassiana, e 73% menores para M. anisopliae. A técnica para avaliação da viabilidade da suspensão preparada com produtos formulados em óleo se mostrou eficaz, após a retirada do óleo da suspensão e outras adaptações. Suspensões de produtos e formulações a base de B. bassiana e M. anisopliae foram mantidas a 26°C, 36°C e 46°C por 1h, 4h e 6h e os efeito destes tratamentos foram medidos na viabilidade e virulência dos fungos contra lagartas de Diatraea saccharalis. Verificou-se que quanto maior o tempo de exposição e maior a temperatura, maior é a influência negativa nos parâmetros dos fungos. Entretanto, a formulação em óleo emulsionável foi a que apresentou melhor proteção aos efeitos detrimentais da temperatura. Mesmo após 6h de exposição a temperatura de 36°C a viabilidade se manteve acima dos 85% para ambos os fungos avaliados. Esta formulação também apresentou os melhores resultados de mortalidade dos insetos, e mesmo após 4h de exposição a 46°C atingiu 39% e 50% de eficiência para B. bassiana e M. anisopliae, respectivamente, sendo recomendável para o controle de D. saccharalis. O protocolo para avaliação da viabilidade de conídios de fungos entomopatogênicos proposto constitui-se como uma ferramenta importante para estudos da influência de fatores bióticos e abióticos durante o período de pré-aplicação na eficiência de micoinseticidas.
This study aimed to evaluate, under laboratory conditions, the influence of temperature and exposure time on the viability and virulence of Beauveria bassiana and Metarhizium anisopliae in suspensions prepared with pure conidia, rice plus fungus and in formulations of wettable powder and concentrated suspension in emulsifiable oil. Initially, an efficient and economical methodology was developed to evaluate conidia viability for each formulation, especially for products formulated in emulsifiable oil mixed in water (suspension of application). During the development of the methodology, the influence of culture media, antibiotics and fungistatics and appropriate conditions were defined for each formulation. Briefly, the established protocol was based on plating 150 L of suspensions containing between 0.7 and 1×106 conidia/mL on a plate type Rodac® with 5 ml of Potato Dextrose Agar culture medium plus 5 mg/L pentabiotic® and 10mg/L and 10 µL/L Derosal® (Carbendazim) and the subsequent counting of germinated conidia. This method was compared to a direct counting (DC) technique, the technique of colony-forming unit (CFU) and viability through fluorescence. The precision of each methodology was measured by their coefficient of variability (CV). Besides its easiness of execution, the new developed methodology was the most precise of all methods (with CV up to 7 times lower compared to the DC, and up to 32 times lower than the UFC). Our results showed that the technique of UFC is not appropriate for evaluation of formulated products, as compared to the conidial quantification by hemacytometer, this technique underestimated the viable concentration in most forms of fungi tested, and for the products in emulsifiable oil these values were 54% lower for B. bassiana, and up to 73% lower for M. anisopliae. The technique for assessing the viability of the suspension prepared with products formulated in emulsifiable oil was effective, after the removal of oil from the suspension and others adaptations. The effect of temperature and period of time on conidia viability of B. bassiana and M. anisopliae-based products and formulations and their virulence against larvae of Diatraea saccharalis was measured at 26°C, 36°C and 46°C for 1h, 4h and 6h. The longer the time of heat exposure and the higher the temperature, the greater the negative influence on vital parameters of the fungi. However, the emulsifiable oil formulation was the least affected by the detrimental effects of heat for both fungi. Even after 6 hours of exposure to temperature of 36°C, the viability remained above 85% for both species evaluated. This formulation also showed the best results of insect mortality, and even after 4h of exposure to 46°C the efficiency was 39% (for B. bassiana) and 50% (for M. anisopliae), and therefore can be useful for control of D. saccharalis. The proposed protocol of evaluation of entomopathogenic fungi viability is a valuable tool for studies of biotic and abiotic factors effect on efficiency of micoinsecticides during the pre-application period.

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Antoun, Mandy C. "Etude de la diversité des bactéries du sol et caractérisation de nouvelles souches de Bacillus thuringiensis actives sur les diptères." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS288.

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Les études de la diversité et de la richesse bactérienne des sols constituent un enjeu primordial pour développer des bio pesticides efficaces en lutte biologique contre les diptères phytoravageurs et vecteurs de maladie (malaria, dengue…). Dans ce manuscrit, la caractérisation de la diversité bactérienne des sols de chênes et de pins Libanais a été étudiée par comparaison aux mêmes sols d’Autriche, une zone géographique différente et de climat différent. La composition en classes et genres du phylum des Firmicutes et son abondance dans les différents sols étudiés ont été particulièrement caractérisées par des indices de diversité (alpha, bêta, OTUs…) et des méthodes moléculaires (SSCP et qRT-PCR). A partir des sols de pins et de chênes Libanais et précisément à partir de ce phylum, des souches de Bacillusthuringiensis ont été criblées pour leur activité insecticides contre les diptères,Culex pipiens, Aedes albopictus et Anopheles gambiae. Deux souches de Bt ont été sélectionnées. La souche A23 possède toxicité in vivo plus élevée que la souche de référence Bacillus thuringiensis isarelensis (Bti). Cette souche n’a cependant pas révélé de différences génétiques et moléculaires par rapport àBti. La souche H3, quant à elle, a été étudiée étant non cytolytique et présentant une activité insecticide in vivo contre les diptères mais à fortes concentrations par rapport à Bti. Cette souche a révélé un contenu génique et protéique différent de Bti. H3 a probablement un nouveau variant du gène cry4B et du gène cry40connu pour avoir une activité diptéricide. Des investigations supplémentaires sont nécessaires afin de confirmer ces résultats et de comprendre les mécanismes de toxicité de ces deux souches
Studies of bacterial diversity and richness of the soil are keys for developing effective bio pesticides for the bio control against plant pests and Diptera vectors of diseases (malaria, dengue ...). In this manuscript, the characterization of the bacterial diversity of broadleaf and needle Lebanese soils was studied compared to the same soils in Austria, a different geographical area and under different climate. Classes and genera compositions of the Firmicutes phylum and its abundance in the different soils studied were particularly characterized using diversity indices (alpha, beta, OTUs…) and molecular methods (SSCP and qRT-PCR). From the broadleaf and needle Lebanese soils and precisely from this phylum, strains of Bacillus thuringiensis were screened for their insecticidal activity against dipteran larvae, Culex pipiens, Aedes albopictus and Anopheles gambiae. Two Bt strains were selected. A23 strain has toxicity in vivo higher than the reference strain Bacillus thuringiensis isarelensis (Bti). However, this strain didn’t reveal any genetic and molecular differences from Bti. The H3 strain, meanwhile, was being investigated for being non-cytolytic and having an insecticidal activity in vivo against Diptera but at high concentrations compared to Bti. This strain showed a different gene and protein content compared to Bti. H3 probably has a new variant of cry4B gene and a new variant of cry40 gene known to have an insecticidal activity. Additional investigations are needed to confirm these results and to understand the mechanisms of toxicity of these two strains

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Hamrouni, Rayhane. "Criblage, identification, physiologie de croissance et métabolisme de Trichoderma asperellum cultivé sur des substrats solides." Electronic Thesis or Diss., Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0288.

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Suite aux désordres écologiques engendrés par l’utilisation des pesticides chimiques, le marché des biopesticides est en plein essor, même s’il ne représente encore que 2 % du marché des produits phytosanitaires. Le contrôle biologique des ravageurs des cultures représente une solution alternative fiable pour lutter contre les nuisances. Parmi les champignons filamenteux (Beauveria bassiana, Trichoderma harzianum) il existe des souches homologuées pour leurs utilisations dans la lutte biologique. Parmi celles-ci, on trouve les souches de Trichoderma peuvent produire la 6 Pentyl-alpha-Pyrone (6-PP), métabolite secondaire antifongique volatile à forte odeur de noix de coco. Ces molécules bioactives, ainsi que les enzymes et les conidies de Trichoderma présentent un potentiel antifongique intéressant susceptible d’être utilisées pour lutter contre des ravageurs et donc de limiter l'apport de pesticides chimiques. Pour l'ensemble de ces propriétés nous avons étudié la croissance et le métabolisme de 23 souches de Trichoderma utilisées comme agents de contrôle biologique contre d'autres champignons phytopathogènes (Botrytis cinerea). Pour la culture de ces souches nous avons utilisé la Fermentation en Milieu Solide (FMS) sur différents mélanges de coproduits agro-industriels (bagasse de canne à sucre ou sarments de vigne, son de blé ou purée de pommes de terre, moringa ou jatropha, chitine ou huile d’olive grignons d'olive ou grignon d’argan). L’objectif recherché est l'obtention d'un produit fermenté contenant un cocktail d'enzymes lytiques, une concentration élevée en 6-PP et une concentration très élevée de conidies viables et virulentes
Biopesticides are placed as a viable alternative to control pests and as a possible substitute for the traditional chemical that causing severe damages to human health, to ecology by non-target organisms eliminated and the creation of pests resistant to pesticides. Trichoderma is a filamentous fungus considered as biocontrol agent (BCA). During their development, Trichoderma produce biomass, lytic enzymes, conidia and secondary metabolites like 6-pentyl-alpha-pyrone (6-PP), a fungicidal compound. The aim of this thesis is the production of these 6-PP, lytic enzymes (cellulases, lipases, amylases) and conidia through the cultivation of the fungus on solid medium. The choice of solid state fermentation (SSF) as cultivation method is not only driven by quantitative and qualitative considerations, but also by economical aspect. In fact, SSF allows the valorization of agroindustrial wastes having an impact on the worldwide ecology. First, this work deals the screening and identification based on internal transcribed spacer (ITS) sequence analysis of Trichoderma strains derived from different natural sources on solid media for 6-PP and conidia production. The second part of this work focuses on the optimization of culture condition using experimental methodology in order to increase enzymes (cellulases, lipases, amylases) conidia and 6-PP production. For this purpose, an original optimization strategy is proposed to overcome specific valorization of wastes generated by agroindustrial. Finally, a scale transfer of the production is advanced by means of an innovative prototype single used bioreactor producing fermented material

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Lima, Andreísa Fabri. "Potencial bioativo e investigações químicas de Solanaceae em relação a Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-10082017-084443/.

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Visando explorar o potencial bioativo de plantas da família Solanaceae como fonte alternativa para o manejo de Spodoptera frugiperda (Lepidoptera: Noctuidae), a lagarta-do-cartucho-do-milho, realizou-se, primeiramente, uma triagem de extratos etanólicos preparados de diferentes partes de 25 espécies vegetais. Após sete dias de exposição das lagartas em dietas tratadas, constatou-se que os extratos etanólicos de folhas de Acnistus arborscens e de Datura stramonium, na concentração de 4.000 mg kg -1, foram os mais promissores causando inibição do ganho de peso de 97,85 e 95,72%, respectivamente. A seguir, foi realizado um fracionamento biomonitorado, a partir do qual, a fração diclorometânica foi selecionada como a mais ativa para essas duas espécies, causando efeito subletal (inibição do ganho do peso) e letal (mortalidade), porém este inferior ao causado pela formulação comercial Azamax® 1,2 EC (controle positivo). Em sequencia, foi possível estimar as concentrações letais para as frações diclorometânicas durante o período de 168 horas. Em relação ao efeito sobre o desenvolvimento do inseto, os extratos etanólicos foram testados na concentração de 4.000 mg kg -1 e as frações diclorometânicas na concentração letal mediana (4.088 e 3.694 mg kg -1 para D. stramonium e A. arborescens, respectivamente). Na fase larval, os extratos etanólicos de D. stramonium e A. arborescens ocasionaram 77,50 e 62,50% de mortalidade, respectivamente, e, além disso, ambos os tratamentos causaram alongamento dessa fase, e mortalidade, deformidade e redução do peso pupal. A fração diclorometânica de A. arborescens proporcionou 100% de mortalidade das lagartas expostas, enquanto a mortalidade em D. stramonium foi 83,19% e, as lagartas necessitaram de 41,75 dias para atingir a fase pupa, que apresentou baixo peso (158,60 mg) e altas deformidades (40%) em comparação ao controle (255,90 mg e 8,26%, respectivamente). Além disso, as frações diclorometânicas ocasionaram atividade fagodeterrente nas CL25, CL50 e CL90. Novamente, utilizando-se a fração diclorometânica, foi realizado novo fracionamento, e após sete dias de exposição das lagartas neonatas, todas as subfrações ocasionaram efeitos subletais. Com isso, tornaram-se necessárias novas investigações químicas a fim de se compreender o (s) composto (os) responsável (is) pela bioatividade, porém a complexidade de algumas subfrações não permitiu uma caracterização química. Ainda assim, foi constatada nas subfrações acetato de etila e metanólica de D. stramonium a presença de compostos pertencentes à classe dos vitanolidos. Dessa forma, os derivados de Solanaceae apresentam potencial bioativo passíveis de serem estudados mais profundamente visando ao emprego dos mesmos no manejo de S. frugiperda.
Aiming to explore the bioactive potential of Solanaceae plants as alternative resources for the management of Spodoptera frugiperda (Lepitoptera: Noctuidae), the fall armyworm, it was performed, firstly, a screening of ethanolic extracts prepared from different parts of 25 plant species. After seven days of exposure of caterpillars to treated diets, it was verified that ethanolic extracts of Acnistus arborscens and Datura stramonium leaves in the concentration of 4,000 mg kg-1 were the most promising, causing an inhibition of 97.85% and 95.72%, respectively, in weight gain. After this, a bioguided fractionation was performed, from which the dichloromethane fraction was selected as the most active in both species, causing sublethal (inhibition of weight gain) and lethal (mortality) effects, although both were less effective than the Azamax® 1,2 EC commercial formulation (positive control). Following the previous step, it was possible to estimate the lethal concentrations for dichloromethane fraction during the period of 168 hours. In relation to the effect on the insect development, the ethanolic extracts were tested in the concentration of 4,000 mg kg-1 and the dichloromethane fractions in their median lethal concentrations (4,088 and 3,694 mg kg-1 for D. stramonium and A. arborescens, respectively). In the larval phase, ethanolic extracts of D. stramonium and A. arborescens lead to 77.50% and 62.50% of mortality, respectively, and both treatments lead to the elongation of this phase, mortality, deformity and pupal weight reduction. The dichloromethane fraction of A. arborescens lead to 100% of mortality of the exposed caterpillars, while mortality of D. stramonium was 83.19%, and the caterpillars needed 41.75 days to reach the pupal stage, which presented low weight (158.60 mg) and were highly deformed (40%) in comparison with the negative control (255.90 mg and 8.26%, respectively). Furthermore, the dichloromethane lead to antifeedant activity in CL25, CL50 and CL90. Once again, using the dichloromethane fraction, another fractionation was performed, and after seven days of exposure of neonates caterpillars, all subfractions lead to sublethal effects. Therefore, new chemical evaluations are necessary to understand the compounds responsible for bioactivity, however, the complexity of some subfractions did not permit chemical characterization. Nevertheless, it was verified in the ethyl acetate and methanolic subfractions of D. stramonium the presence of withanolides compounds. Therefore, derivatives of Solanaceae present bioactive potential that may be liable for further evaluation aiming their employment in the management of S. frugiperda.

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Billet, Kévin. "Plasticité génotypique et environnementale du métabolisme des polyphénols dans des coproduits viticoles à visée antifongique." Thesis, Tours, 2019. http://www.theses.fr/2019TOUR4012.

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La viticulture est fortement dépendante de l’utilisation de produits phytosanitaires et très peu de solutions alternatives sont aujourd’hui disponibles. Les sarments de vigne sont des coproduits très largement disponibles et peu valorisés qui accumulent des polyphénols possédant des activités contre le mildiou de la vigne. Ce travail contribue au développement d’extraits de sarments de vigne à visé anti-mildiou en s’appuyant sur des expérimentations au vignoble et des approches métabolomiques pour l’analyse des polyphénols. Les essais au champ sur trois ans et trois cépages sensibles au mildiou apportent des résultats encourageants pour le biocontrôle de Plasmopara viticola sur feuilles comme sur grappes. Des analyses métabolomiques ciblées par UPLC-DAD-MS d’extraits de sarments ont permis de discriminer huit cépages principaux du Val de Loire montrant ainsi le déterminisme génétique de la signature en polyphénols. Le criblage métabolomique d’une large collection génétique de cépages européens a permis d’identifier des cépages élites pour la production de polyphénols. Enfin, une étude métabolomique spatialisée à l’intérieur d’une parcelle a montré que les profils métaboliques des sarments de vigne sont également dépendants des facteurs environnementaux et notamment de la texture du sol
Viticulture strongly relies on agrochemical products and only few alternative solutions are available. Grape stems are abundant byproducts rich in polyphenols with antifungal activities. This work aims to develop grape stem extracts with antifungal activities based on field-experiments and metabolomics approaches for the analysis of polyphenols. A large-scale study in vineyards showed encouraging results for the biocontrol of Plasmopara viticola on both leaves and clusters. UPLC-DAD-MS-based targeted metabolomics of grape stems discriminates eight representative varieties of Loire Valley, thus showing the genetic determinism of polyphenol signature. Metabolomic screening of a large germplasm collection of European grape varieties allowed to selection of polyphenol-rich varieties. Finally, spatialized metabolomics within a vineyard parcel showed that polyphenol composition in grape stems also depends on environmental cues particularly soil texture

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El, Arbi Amel. "Isolement, identification et caractérisation des Bacillus spp. de sol d’oasis tunisien et leurs potentialités d’utilisation en lutte biologique." Thesis, Lille 1, 2016. http://www.theses.fr/2016LIL10157.

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Ce travail de thèse a pour objectif la recherche et le criblage de bactéries capables de jouer un rôle important dans la lutte biologique contre les champignons phytopathogènes. L'isolement des bactéries a été réalisé à partir de sols rhizosphériques de palmier dattier. 5 souches parmi les 28 isolées présentent un pouvoir antagoniste et ont été identifiées comme membres du genre Bacillus. La présence des gènes de biosynthèse de lipopeptides a été détectée par PCR, la production des lipopeptides a été confirmée par spectrométrie de masse Maldi-TOF. Ces isolats se caractérisent aussi par leur tolérance aux stress abiotiques (salinité, température élevée et stress hydrique). La souche Bacillus sp III1 qui a montré la production de trois familles de lipopeptides (surfactine, fengycine et iturine) et qui possède le plus fort pouvoir antifongique a fait l’objet d’une évaluation de son potentiel de biocontrôle de la septoriose, principale maladie du blé. L’effet inhibiteur du filtrat de culture de la souche III1 sur la croissance et la germination de Zymoseptoria tritici, agent causal de la maladie du blé, a été démontré in vitro et in planta. Le filtrat de culture pur et dilué à 25 et 50 % réduit jusqu’à 95% les symptômes de la maladie. Ensuite, l’iturine produite par Bacillus spp. III1 a été identifiée comme étant de la mojavensine. Les conditions environnementales optimales de production de la mojavensine (pH, température et aération) ont été déterminées en utilisant la méthode des plans d’expériences. Finalement, une optimisation des conditions environnementales de la pumilacidine, lipopeptide produit par Bacillus pumilus I2 a été réalisée
The aim of this thesis was to screen bacteria isolated from the rhizosphere of the date palm tree for their ability to inhibit phytopathogenic fungi. Screening for antifungal activity was performed on twenty-eight isolates. Five antagonistic isolates were selected and identified as members of Bacillus genera. The five antagonistic Bacillus isolated showed tolerance to abiotic stresses (high temperature, salinity, drought). The presence of biosynthetic genes encoding lipopeptides was investigated by PCR and lipopeptide production was confirmed by MALDI-ToF mass spectrometry. The antagonistic Bacillus spp. III1 strain that produced a high diversity of lipopeptides belonging to surfactin, fengycin and iturin families and that showed the strongest antifungal activity was evaluated for biocontrol of Septoria tritici blotch, one of the most important foliar pathogens of wheat. The inhibitory effect of the culture filtrate of the strain III1 on growth and germination of Zymoseptoria tritici, the causal agent of wheat disease, was demonstrated in vitro and in planta. The pure culture filtrate and diluted to 50% and 25 % reduced up to 95% the symptoms of the disease. Then iturin produced by Bacillus spp. III1 was identified as mojavensine. The optimum environmental conditions for producing mojavensin (pH, temperature and ventilation) were determined using the method of design of experiments. Finally, optimization of the environmental conditions of the pumilacidin, lipopeptide produced by Bacillus pumilus I2 was performed

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48

Vidal, Quist José Cristian. "Estrategias para la utilización de la bacteria entomopatógena Bacillus thuringiensis (Berliner) en el control de Ceratitis capitata (Wiedemann)." Doctoral thesis, Universitat Politècnica de València, 2010. http://hdl.handle.net/10251/8336.

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La mosca mediterránea de la fruta, Ceratitis capitata, es la principal plaga de la fruticultura en el mundo. El desarrollo de métodos ambientalmente seguros de control de plagas, como Bacillus thuringiensis (Bt), adquiere cada vez mayor importancia. Esta tesis doctoral evalúa la validez de Bt y sus delta-endotoxinas como agentes de control de C. capitata. El análisis de la biodiversidad de Bt ha reflejado la gran riqueza presente en el agroecosistema de los cítricos. Sin embargo, ninguna de las cepas ensayadas (905) muestra alta toxicidad sobre C. capitata cuando esporas/cristales o sobrenadantes de su cultivo son ensayados. En cambio, la solubilización de los cristales de una selección de 42 cepas de Bacillus sp. ha demostrado que, para las cepas de la subespecie israelensis (Bti), este tratamiento produce una ganancia de función biológica. Adicionalmente, la predigestión de dichas protoxinas con proteasas de otro díptero, Culex pipiens, aumenta su actividad larvicida (CL50 31.26 µg/cm2). Por otro lado, se ha demostrado que, entre las delta-endotoxinas producidas por Bti, la protoxina Cyt1Aa es el factor determinante, con una CL50 sobre larvas de 4.93 µg/cm2. Sobre adultos, Cyt1Aa produce efectos subletales. Complementariamente, esta tesis propone un nuevo método de control basado en el desarrollo de toxinas recombinantes de fusión Cry-anticuerpo. Se ha puesto en práctica un sistema modelo para evaluar esta estrategia: se han desarrollado 4 variantes proteicas por la fusión entre partes de la protoxina Cry1Ab y un anticuerpo específico contra GFP (VHH anti-GFP) y éstas se han ensayado sobre larvas transgénicas de Drosophila melanogaster que expresan GFP en su intestino. Deficiencias en la unión de las toxinas de fusión a GFP, han impedido demostrar, por el momento, la estrategia propuesta. Por último, se han detectado al menos 160 proteínas distintas en las membranas intestinales de C. capitata y se han identificado las siguientes: V-ATPasa subunidades A y B, y alfa-tubulina.
Vidal Quist, JC. (2010). Estrategias para la utilización de la bacteria entomopatógena Bacillus thuringiensis (Berliner) en el control de Ceratitis capitata (Wiedemann) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8336
Palancia

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Ballardo, Matos Cindy Vanessa. "Valorización de residuos sólidos orgánicos como sustrato para el crecimiento de Bacillus Thuringiensis mediante fermentación en estado sólido: aplicación a la fracción orgánica de residuos municipales para la producción de compost con efecto biopesticida." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/399721.

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Ante la creciente producción de residuos a todos los niveles se ha investigado la posible utilización de estos como materia prima. Esta investigación persigue la valorización de residuos sólidos orgánicos como sustrato para el crecimiento de Bacillus thuringiensis utilizando la Fermentación en Estado Sólido (FES). El Bacillus thuringiensis es una bacteria empleada como agente de control biológico para el control selectivo de insectos plaga. El objetivo principal del trabajo ha sido determinar la factibilidad de utilizar residuos orgánicos sin pre-tratamiento previo a una escala piloto. Se trabajó en 4 fases principales: en la primera fase se utilizó el residuo de soja a escala laboratorio y en reactores de 10 L mediante la FES; en la segunda fase se utilizó la Fracción Orgánica de Residuos Municipales de la recogida selectiva (FORM) esterilizado y sin esterilizar, mediante la fermentación sumergida (FmS); en la tercera fase también se utilizó la FORM esterilizada y sin esterilizar mediante diferentes estrategias en fermentación en estado sólido (FES); y en la última fase se utilizaron residuos de fruta y verduras (asimilable a residuos de cocina) a escala real (400 L), en compostador casero. Además en la última fase se evaluó la toxicidad del compost para su utilización como enmienda orgánica en el suelo. Se he determinado la viabilidad del crecimiento en condiciones estériles a temperatura constante de 30°C y en FES del Bt, tanto en resid uo de soja como en FORM. Se ha demostrado la supervivencia del Bt en residuo de soja en FES a temperatura no controlada a escala de 4.5L y 10 L manteniéndose constante la población aún a temperaturas por encima de los 60°C. Por lo que a l a FORM se refiere, se han optimizado las condiciones de proceso hasta conseguir escalar a reactores de 10 L en producto de la FES higienizado donde el Bt creció en una estrategia de operación que permite desarrollar el proceso en semicontínuo. Aplicado a compostador doméstico, se consigue un producto final conteniendo Bt sin efectos tóxicos para el suelo. Además esta investigación da apertura al estudio y desarrollo de un compost con propiedades biopesticidas. Este es el primer trabajo desarrollado en este campo dentro del grupo de compostaje de la UAB y tendrá continuidad en el marco del proyecto europeo DECISIVE (H2020).
Given the growing generation of solid residues, several attempts have been made to exploit these residues as raw material for diverse applications. This study focuses on the valorization of solid organic residues of different characteristics as substrate for the growing of the strain Bacillus thuringiensis (Bt) through the solid state fermentation (SSF) process. Bt is a bacteria employed as biological pest control for the selective control of some insects. The aim of the study is the assessment of diverse process strategies in order to identify the feasibility of growing for the Bt at 0.5L, 4.5L, 10L and 400L with and without sterilization of the residues. Four main stages have been evaluated: First, using soy fiber residues at 0.5 and 10L scale. Second, by means of the organic fraction of municipal solid waste (OFMSW) through submerged fermentation (SmF). Third, working with different strategies the OFMSW through SSF, and finally, with the organic fraction of kitchen residues (KR) in a home composting system (400L), testing additionally, the toxicity of the final compost. It was found that Bt is able to grow properly when soy fiber residues and OFMSW were sterilized, working the SSF at constant temperature (30°C). Similarly, at non controlled temperature processes (4.5L and 10L), Bt survived even when temperatures reached values beyond 60°C, remaining the Bt concentration in a similar level than the initial one. Regarding OFMSW, SSF process has been optimized in a 10L scale. In this scenario a semi-continuous strategy allows Bt to grow in the solid medium, reaching a final hygienic compost material with a Bt load that gives the material biopesticide properties. In the case of the home composting system, the final product also contains a significant Bt population remaining a non-toxic material for the soil. It is remarkable that Bt has grown in solid medium, and there is no need for sterilization of the residues for achieving good results. Considering this, presented strategies are a first approach to obtain compost with biopesticides properties. This is the first project in this area, developed by the UAB composting research group. It will be further and deeply investigated in the framework of the European project DECISIVE (H2020).

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Silva, Bianca Carvalho da. "Avaliação da toxicidade de quatro solventes e um surfactante, e dos fenilpropanoides eugenol e (E)-cinamaldeído sobre larvas e pupas de Musca domestica Linnaeus, 1758 (Diptera: Muscidae)." Universidade Federal de Juiz de Fora (UFJF), 2016. https://repositorio.ufjf.br/jspui/handle/ufjf/4062.

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Musca domestica é um importante vetor mecânico de diversos patógenos para humanos e animais de criação, sendo essencial o estudo de novas alternativas de controle mais eficientes e seguras para este díptero. A busca por novas alternativas de inseticidas envolve experimentos que geralmente necessitam do uso de solventes que não interfiram nos resultados da substância testada. Assim, o presente estudo compreendeu duas etapas: investigar a sensibilidade de larvas e pupas de M. domestica aos solventes acetona, etanol, metanol e dimetilsulfóxido (DMSO) e ao surfactante Tween 80 em diferentes tempos de volatilização; e avaliar a toxicidade dos fenilpropanoides eugenol e (E)-cinamaldeído sobre os mesmo estágios deste díptero. Para ambos os experimentos utilizou-se o teste de contato, com 10 repetições (n=10) para cada solvente/surfactante e concentração das substâncias sobre cada estágio. No primeiro experimento foram testados acetona, etanol e metanol em pureza analítica e DMSO e Tween 80 na concentração de 5%. Os tempos avaliados foram zero, cinco, 10 e 15 minutos (23±2°C e 60±10% UR). Os resultados mostraram que o tempo de volatilização produz diferença significativa na mortalidade larval (ML) para os três primeiros solventes testados, e acetona mostrou-se semelhante ao controle após cinco minutos de volatilização (p>0,05). Metanol e etanol mostraram-se semelhantes ao controle após 15 minutos de volatilização (p>0,05). DMSO não apresentou ML significativa (p>0,05), no entanto apresentou percenbtual de mortalidade acumulada (PMA) superiores a 14% (p<0,05). Tween 80 não apresentou diferença na toxicidade sobre as larvas relacionada ao tempo. Para o teste com pupas somente etanol produziu diferença significativa entre os tempos de volatilização, enquanto acetona e metanol diferiram do controle em todos os tratamentos (p<0,05). DMSO e Tween 80 não diferiram significativamente do controle em nenhum tempo (p˃0,05). O surfactante Tween 80 foi o único que não apresentou toxicidade para ambos os estágios na concentração testada, porém acetona foi o solvente que volatilizou mais rapidamente, mostrando menor toxicidade entre aqueles testados em pureza analítica. Para o segundo experimento, foram utilizadas oito concentrações de cada substância para a determinação das concentrações letais (CL50 e CL90). Eugenol apresentou os menores valores de CL50 e CL90, para a eficácia do tratamento larval (ETL) (1,5 e 3,75 mg/mL, respectivamente) enquanto (E)-cinamaldeido apresentou os menores valores de CL50 e CL90 para a eficácia do tratamento pupal (ETP) (18,08 e 78,83 mg/mL, respectivamente). Ambas as substâncias apresentaram atividade larvicida a partir de 2,5 mg/mL e ETL de 100% a partir de 5 mg/mL. Para o tratamento pupal (E)-cinamaldeído diferiu do controle a partir da 13 concentração de 10mg/mL (p<0,05) e ambos os fenilpropanoides causaram má formação em adultos a partir de 10 mg/mL, e maior ETP na concentração de 30 mg/mL, sendo 67,2% para (E)-cinamaldeído e 32% para eugenol. Os produtos testados nesse estudo apresentaram elevado potencial larvicida, além de ambos apresentarem efeitos pupicida e causarem má formação nos adultros provenientes de pupas tratadas. Ainda, é possível sugerir a utilização conjunta de ambas substância para um controle mais eficiente, visto que (E)-cinamaldeído apresentou melhor atividade larvicida, enquanto eugenol teve melhor atividade pupicida. Desta forma, esses fenilpropanoides mostrando-se promissores para o uso no desenvolvimento de formulações mais seguras para a saúde e meio ambiente, sendo possível sua utilização em estratégias de Manejo Integrado de Pragas.
Musca domestica is an important mechanical vector of several pathogens to humans and domestic animals, being essential to study new alternatives to eficiente and safe control against this Diptera. The search for new insecticides alternative involves experiments that generally require the use of solvents that should not interfere in the results of the test substance. Thus, this study involved two stages: to investigate the sensitivity of M. domestica larvae and pupae to the solvents acetone, ethanol, methanol and dimethylsulfoxide (DMSO) and the surfactant Tween 80 at different times of volatilization; and evaluating toxicity of phenylpropanoid eugenol and (E)-cinnamaldehyde against the same stages of this Diptera. For both experiments were used the patch test with 10 repetitions (n=10) for each solvent/surfactant and concentration of substances against each stage. In the first experiment acetone, ethanol and methanol were tested in analytical purity while DMSO and Tween 80 at the concentration of 5%. The times evaluated were zero, five, 10 and 15 minutes (23±2°C and 60±10% RH). The results showed that the volatilization time produces significant difference in larval mortality (LM) for the first three solvents tested, and acetone was similar to the control after five minutes volatilization (p>0.05). Methanol and ethanol were similar to the control after 15 minutes of evaporation (p>0.05). DMSO showed no significant LM (p> 0.05), but its accumulated mortality percenbtual (AMP) was over 14% (p<0.05). Tween 80 showed no difference in toxicity againts larvae related to time. For the pupae test only ethanol produced significant difference between the evaporation time, while acetone and methanol differed from the control in all treatments (p<0.05). DMSO and Tween 80 did not differ significantly from control at any time (p>0.05). The surfactant Tween 80 was the only one that showed no toxicity for both stages at the concentration tested, however the solvent acetone was volatilized more quickly, showing lower toxicity among those tested in analytical purity. For the second experiment, we used eight concentrations of each substance for the determination of lethal doses (LC50 and LC90). Eugenol showed the lowest values of LC50 and LC90 for the effectiveness of larval treatment (ELT) (1.5 and 3.75 mg/mL, respectively) while (E)-cinnamaldehyde had the lowest values of LC50 and LC90 for effectiveness of pupal treatment (EPT) (18.08 and 78.83 mg/mL, respectively). Both substances exhibited larvicidal activity from 2.5 mg/mL and ELT of 100% from 5 mg/mL. For pupal treatment (E)cinnamaldehyde differed from the control from the concentration of 10mg/mL (p <0.05) and both phenylpropanoid caused malformation in adults from 10 mg/mL. The greater EPT was from concentration of 30 mg/mL, being 67.2% for (E)-cinnamaldehyde and 32% for eugenol. 15 The products tested in this study had high potential larvicide, and both present pupicida effects and cause malformation in adultros from treated pupae. Still, it is possible to suggest the combined use of both substance for more efficient control, as (E)-cinamaldeído showed better larvicidal activity, while eugenol had better pupicida activity. Thus, using these phenylpropanoids show promise in the development of safer formulations for health and the environment, and these could be used in Integrated Pest Management strategies.

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