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1
Lubbe, Carolien M. "Colletotrichum diseases of Proteaceae." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/53732.
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Thesis (MSc)--Stellenbosch University, 2004.ENGLISH ABSTRACT: This thesis consists of four chapters that present research findings on Colletotrichum diseases associated with Proteaceae worldwide. The first chapter is a review of literature regarding the taxonomy and histology of Colletotrichum species associated with Proteaceae. The literature is not restricted to Proteaceae hosts, as information regarding Colletotrichum on Proteaceae is very limited. In chapter two, Colletotrichum spp. associated with proteaceous hosts growing in various parts of the world were identified based on morphology, sequence data of the internal transcribed spacer region (ITS-I, ITS-2), the 5.8S gene, and partial sequences of the B-tubulin gene. Four species of Colletotrichum were associated with Proteaceae. Colletotrichum gloeosporioides was isolated from Protea cynaroides cultivated in South Africa and Zimbabwe and from a Leucospermum sp. in Portugal, but is known to occur worldwide on numerous hosts. A recently described species, C. boninense, was associated with Zimbabwean and Australian Proteaceae, but also occurred on a Eucalyptus sp. in South Africa. This represents a major geographical and host extension for the species, and a description of the African strains is provided. Colletotrichum crassipes was represented by a single isolate obtained from a Dryandra plant in Madeira. Colletotrichum acutatum was isolated from Protea and Leucadendron in South Africa as well as from other proteaceous hosts occurring elsewhere. Colletotrichum acutatum f. sp. hakea was isolated from Hakea in South Africa. In chapter three, pathogenicity of these Colletotrichum species to certain proteas was established, relative aggressiveness of the different species tested and host response to them were compared as well as the effect that wounding had on host response. From the results obtained it is concluded that C. acutatum and C. gloeosporioides are the primary pathogens associated with Colletotrichum leaf necrosis, and C. acutatum is the main cause of anthracnose and stem necrosis of Proteaceae in South Africa. A histological study was performed in chapter four in response to the findings from the previous chapter. The behaviour of two C. acutatum isolates (one originating from Protea and the other from Hakea, C. acuataum f.sp. hakea) was studied on inoculated Protea leaf surfaces using light and scanning electron microscopy. Colletotrichum acutatum from Protea formed melanised appressoria on the leaf surface, whereas C. acutatum from Hakea formed very low numbers of both melanised and unmelanised appressoria. Most of the appressoria formed by C. acutatum from Protea were formed on the cell junctions and on the periclinal walls of the epidermal cells. From this study it is clear that C. acutatum f. sp. hakea is not a pathogen of Protea. Consequently the current use of this isolate as a biological control agent of Hakea in South Africa poses no threat to indigenous Protea species. Colletotrichum acutatum from Protea (although closely related to C. acutatum f. sp. hakea), is a pathogen of Protea, which was confirmed by histological observations. In conclusion, the present study has shown that several species of Colletotrichum are associated with diseased Proteaceae. These species differed in their pathogenicity and aggressiveness when inoculated onto certain protea cultivars. These differences could be partially explained by examining the behaviour of C. acutatum on the leaf surface. It is clear, however, that the distribution of the different species, their aggressrveness on different Proteaceae and their modes of infection needs to be investigated further. This work provides a basis for future research on the long-term effective management of these pathogens in fynbos production.
AFRIKAANSE OPSOMMING: Hierdie tesis bestaan uit vier hoofstukke wat handeloor navorsing van Colletotrichum siektes van Proteaceae wêreldwyd. Die eerste hoofstuk is 'n oorsig van literatuur rakende die taksonomie en histologie van die Colletotrichum spesies wat met Proteaceae geassosieer word. Die literatuur oorsig is nie beperk tot die Proteaceae nie aangesien baie min inligting rakende Colletotrichum op Proteaceae bestaan. In die tweede hoofstuk word die Colletotrichum spesies wat met proteas in verskeie dele van die wêreld geassosieer word, op grond van morfologie, DNS volgorde data van die interne getranskribeerde spasieerder area ("ITS-I, ITS-2"), die 5.8S geen, en gedeeltelike DNS volgordes van die B-tubulin geen geïdentifiseer. Vier Colletotrichum spesies is met die Proteaceae geassosieer. Colletotrichum gloeosporioides is geïsoleer vanaf Protea cynaroides wat in Suid-Afrika en Zimbabwe gekweek is en vanaf 'n Leucospermum sp. in Portugal, maar is bekend op verskeie gashere wêreldwyd. 'n Spesie wat onlangs beskryf is, C. boninense, is met Zimbabwiese en Australiaanse Proteaceae geassosieer, maar kom ook op 'n Eucalyptus sp. in Suid-Afrika voor. Dit is 'n groot uitbreiding van die geografiese voorkoms en gasheerreeks van hierdie spesie en 'n beskrywing van die Afrikaanse rasse word gegee. Colletotrichum crassipes is verteenwoordig deur 'n enkele isolaat wat vanaf 'n Dryandra plant in Madeira verkry is. Colletotrichum acutatum is vanaf Protea en Leucadendron in Suid-Afrika asook vanaf ander proteas wat elders voorkom, geïsoleer. Colletotrichum acutatum f. sp. hakea is vanaf Hakea in Suid-Afrika geïsoleer. In hoofstuk drie is die patogenisiteit van hierdie Colletotrichum spesies teenoor sekere proteas getoets, die relatiewe aggressiwiteit van die verskillende spesies is vergelyk, asook die gasheer se reaksie teenoor die spesies en die effek wat verwonding op die gasheer gehad het. Daar kan afgelei word vanaf die resultate dat C. acutatum en C. gloeosporioides die primêre patogene is wat met Colletotrichum blaarnekrose geassosieer word, en dat C. acutatum die hoof oorsaak is van antraknose en lootnekrose van Proteaceae in Suid-Afrika. 'n Histologiese studie is in hoofstuk vier uitgevoer in reaksie op die bevindings van die vorige hoofstuk. Die gedrag van twee C. acutatum isolate (een vanaf Protea en die ander vanaf Hakea, C. acutatum f.sp. hakea) op die oppervlaktes van geïnokuleerde Protea blare is bestudeer deur gebruik te maak van lig- en skandeer-elektronmikroskopie. Colletotrichum acutatum vanaf Protea vorm gemelaniseerde appressoria op die blaaroppervlak, terwyl C. acutatum vanaf Hakea klein hoeveelhede van beide gemelaniseerde en ongemelaniseerde appressoria vorm. Meeste van die appressoria wat deur C. acutatum vanaf Protea gevorm word, vorm op die aanhegtingspunte tussen selle en op die periklinale wande van die epidermale selle. Vanuit hierdie studie is dit duidelik dat C. acutatum f. sp. hakea nie 'n patogeen van Protea is nie. Gevolglik hou die huidige gebruik van hierdie isolaat as biologiese beheer agent van Hakea in Suid-Afrika geen gevaar in vir inheemse Protea spesies nie. Colletotrichum acutatum vanaf Protea (alhoewel dit naverwant is aan C. acutatum f. sp. hakea) is 'n patogeen van Protea en hierdie stelling is ook bevestig deur histologiese waarnemmgs. Ter samevatting het hierdie studie getoon dat verskeie Colletotrichum spesies geassosieer word met siektes van Proteaceae. Hierdie spesies het van mekaar verskil rakende patogenisiteit en aggressiwiteit nadat hulle op sekere protea kultivars geïnokuleer is. Hierdie verskille kon gedeeltelik verklaar word deur die gedrag van C. acutatum op die blaaroppervlaktes van verskillende protea kultivars. Dit is duidelik dat die verspreiding van die verskillende spesies, hulle aggressiwiteit op verskillende Proteaceae en hul infeksie metodes verder ondersoek moet word. Hierdie studie verskaf 'n basis vir toekomstige navorsing rakende lang-termyn effektiewe bestuur van hierdie patogene in fynbos aanplantings.
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Junior, Hugo Jose Tozze. "Caracterização e identificação de espécies de Colletotrichum associadas à antracnose do pimentão (Capsicum annuum) no Brasil." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-20032008-151208/.
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A antracnose é uma das doenças mais importantes do pimentão em vários países. Por muitos anos, somente C. gloeosporioides foi relatado como agente causal da antracnose desta cultura no Brasil. Entretanto, recentemente C. acutatum e C. capsici também tem sido associados a esta doença em algumas regiões do país. Neste trabalho, 56 isolados de Colletotrichum obtidos de pimentão e procedentes de diferentes regiões produtoras do país foram caracterizados e identificados por meio de algumas características morfológicas e culturais, e pela análise por PCR utilizando oligonucleotídeos espécie-específicos. Isolados representativos de cada espécie identificada na população amostrada também foram caracterizados quanto à patogenicidade em frutos de pimentão verdes e maduros, feridos e não feridos e quanto a sensibilidade aos fungicidas azoxistrobina, carbendazim, tiabendazol, tebuconazol, captana, clorotalonil e cloreto de benzalcônio. Os resultados demonstram que C. acutatum é a espécie predominante nas principais regiões produtoras de pimentão do país, representando cerca de 72% da população amostrada. C. capsici foi encontrada com freqüência aproximada de 14%, nos estados de São Paulo e Minas Gerais. C. gloeosporioides representou apenas 5% da população amostrada e teve distribuição restrita ao estado de São Paulo e ao Distrito Federal. Um único isolado de C. coccodes foi encontrado no Rio Grande do Sul. Além dessas espécies, isolados identificados como C. boninense foram encontrados em São Paulo e no Rio Grande do Sul, com freqüência de 7% na população amostrada. Este parece ser o primeiro relato de C. boninense infectando pimentão no Brasil e em outras partes do mundo. A caracterização patogênica mostrou que isolados representativos de todas as espécies foram patogênicos aos frutos maduros feridos e não feridos. Nos frutos verdes feridos, apenas os isolados de C. acutatum e de C. capsici promoveram sintomas. Não foram observados sintomas nos frutos verdes sem ferimentos durante o período de avaliação do experimento (12 dias) para nenhum dos isolados. C. acutatum demonstrou ser a espécie mais agressiva, apresentando os menores períodos de latência e a maior esporulação tanto em frutos verdes (feridos) como nos maduros (feridos e não feridos). Os isolados pertencentes a diferentes espécies de Colletotrichum apresentaram sensibilidade diferenciada para todos os fungicidas sistêmicos avaliados. Os isolados de C. acutatum foram mais sensíveis a azoxistrobina, enquanto os isolados de C. gloeosporioides demonstraram a menor sensibilidade para este fungicida. Os isolados de C. gloeosporioides e C. boninense foram os mais sensíveis aos benzimidazóis (carbendazim e tiabendazol), enquanto o isolado de C. coccodes teve a menor sensibilidade para estes fungicidas. O fungicida tebuconazol promoveu o maior controle sobre o crescimento micelial dos isolados. Para este fungicida, C. capsici demonstrou ser a espécie menos sensível. Os resultados deste trabalho demonstram a presença de pelo menos cinco espécies de Colletotrichum responsáveis pela antracnose do pimentão no país e evidenciam a presença de importantes diferenças entre essas, que devem ser consideradas durante o manejo da doença.In several countries, anthracnose is one of the most serious diseases in pepper. C. gloeosporioides has, for many years, been reported as the causal agent of anthracnose in Brazil. C. acutatum and C. capsici have only recently been reported as agents of anthracnose in some regions of the country. In this study, 56 isolates of Colletotrichum obtained from pepper from different areas of the country were characterized and identified based on the morphological characteristics of the conidia, as well as culture characteristics and PCR analysis with species-specific pairs of primers. Isolates representative of each identified species in the sampled population were also characterized according to their pathogenicity in pepper fruits (unripe, ripe, wounded and nonwounded) and also according to their sensitivity to fungicide (azoxystrobin, carbendazim, thiabendazole, tebuconazole, captan, chlorothalonil and benzalkonium chloride). The results have showed that C. acutatum is the most prevalent species found in the main production areas of pepper, present in about 72% of the sampled population. C. capsici was equivalent to 14% of the sampled population and found in the states of São Paulo and Minas Gerais. C. gloeosporioides was present in only 5% of the samples and it was restricted to the state of São Paulo and Distrito Federal. Only one isolate of C. coccodes was found in Rio Grande do Sul. Besides theses species, isolates of C. boninense were found in São Paulo and Rio Grande do Sul, with an occurrence of 7% in the sampled population. This seems to be the first report of C. boninense infecting pepper in Brazil and other parts of the world. The pathogenic characterization showed that representative isolates of all species were pathogenic in ripe, wounded, or nonwounded fruits. In wounded green fruit, only isolates of C. acutatum and C. capsici caused infection resulting in disease symptoms. No disease symptoms were observed in green nonwounded fruits inoculated with all Colletotrichum isolates, after 12 days of inoculation. C. acutatum was the most aggressive species with the shortest periods of latency and the highest rate of sporulation in either green wounded fruits or ripe fruits (wounded and nonwounded). Isolates of different species of Colletotrichum showed different sensitivity to the systemic fungicides evaluated. The isolates of C. acutatum were more sensitive to azoxystrobin, whereas C. gloeosporioides showed the lowest sensitivity to this fungicide. C. gloeosporioides and C. boninense isolates were the most sensitive to benzimidazoles fungicides (carbendazim and thiabendazole), whereas C. coccodes isolates showed the lowest sensitivity to these fungicides. The tebuconazol fungicide exerted the highest effect on mycelial growth for all Colletotrichum species. C. capsici showed to be less sensitive to this fungicide. The results of this work have shown the presence of at least five species of Colletotrichum responsible for anthracnose in pepper in Brazil and have made evident the importance of the differences between these species, which must be taken into account for the control of the disease.
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Sierra, Hayer Juan Fernan [UNESP]. "Variabilidade genética de Colletotrichum gloeosporioides e Colletotrichum acutatum em seringueira (Hevea brasiliensis) no Brasil." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/108731.
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000766190.pdf: 2070584 bytes, checksum: 9a03514bca85630b682825636e50389c (MD5)A seringueira [Hevea brasiliensis (Wild. ex Adr. de Juss.) Muell-Arg] é a maior fonte de borracha natural, amplamente cultivada, e de grande importância comercial devido a sua alta capacidade produtiva. Atualmente ela vem sendo atacada por várias doenças que causam enormes prejuízos econômicos. Dentre essas a antracnose, causada pelos fungos Colletotrichum gloeosporioides e Colletotrichum acutatum, está presente em todos os lugares heveícolas do mundo. Estes fungos causam vários danos na planta como lesões nos folíolos, nos ponteiros, nos ramos, nos frutos e cancros no painel de sangria. Diante desta situação e da alta incidência destes patógenos na cultura da seringueira, o presente trabalho teve como objetivo identificar a variabilidade genética dos isolados de C. gloeosporioides e C. acutatum associados à seringueira. Ferramentas filogenéticas e populacionais foram utilizados para determinar a distribuição e a frequência de cada um dos possíveis haplótipos. As 79 amostras coletadas em campo foram amplificadas por PCR com primers específicos das regiões espaçadores ITS e dos genes 18S, 28S e 5,8S. Posteriormente as regiões amplificadas foram sequenciadas pelo método Sanger. Para complementar as análises foram adicionadas sequências disponíveis no NCBI, totalizando uma matriz de dados de 263 amostras. As árvores geradas, a partir de análises filogenéticas Bayesiana, Máxima Verossimilhança e Neighbour-Joining, mostraram a divisão dos grupos de C. gloeosporioides e C. acutatum, possibilitando a separação da matriz em duas espécies específicas. As análises ...
The rubber tree [Hevea brasiliensis (Wild. ex Adr. Than Juss. ) Muell - Arg] is the largest source of natural rubber, widely cultivated, and of great commercial importance due to its high production capacity. Currently the rubber trees are being attacked for various diseases, causing huge economic losses. Among them, the anthracnose, caused by Colletotrichum gloeosporioides and Colletotrichum acutatum, is in all rubber crops places of the world. These fungi causes various damage, such as injuries on leaves, branches, fruits, as well as cankers in the taping panel. Given this situation, and the high incidence of this pathogen in the rubber crop, this study aimed to identify the genetic variability of the isolates of C. gloeosporioides and C. acutatum associated to rubber crop. Phylogenetic and population tools were performed to determine the distribution and frequency of each possible haplotypes. The 79 samples collected in the field were amplified by PCR by specific primers of the ITS spacers regions and the 18S, 28S and 5.8 S genes. Subsequently, the amplified regions were sequenced by the Sanger method. Several sequences available in NCBI were added, to complement the analysis, totaling a data matrix of 263 samples. Phylogenetic analyses generated by Bayesian, Maximum Likelihood and Neighbour -Joining methods, showed the division of the C. acutatum and C. gloeosporioides groups, enabling the separation of the matrix in two specific species. The population analysis showed some very common haplotypes distributed around the world, as well as another haplotypes with very restricted distribution, such as H1 haplotype of ...
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Sierra, Hayer Juan Fernan 1980. "Variabilidade genética de Colletotrichum gloeosporioides e Colletotrichum acutatum em seringueira (Hevea brasiliensis) no Brasil /." Botucatu, 2014. http://hdl.handle.net/11449/108731.
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Orientador: Edson Luiz FurtadoBanca: Martha Maria Passador
Banca: Eduardo Bagagli
Banca: Marli de Fatima Stradioto Papa
Banca: Christiane Ceriane Aparecido
Resumo: A seringueira [Hevea brasiliensis (Wild. ex Adr. de Juss.) Muell-Arg] é a maior fonte de borracha natural, amplamente cultivada, e de grande importância comercial devido a sua alta capacidade produtiva. Atualmente ela vem sendo atacada por várias doenças que causam enormes prejuízos econômicos. Dentre essas a antracnose, causada pelos fungos Colletotrichum gloeosporioides e Colletotrichum acutatum, está presente em todos os lugares heveícolas do mundo. Estes fungos causam vários danos na planta como lesões nos folíolos, nos ponteiros, nos ramos, nos frutos e cancros no painel de sangria. Diante desta situação e da alta incidência destes patógenos na cultura da seringueira, o presente trabalho teve como objetivo identificar a variabilidade genética dos isolados de C. gloeosporioides e C. acutatum associados à seringueira. Ferramentas filogenéticas e populacionais foram utilizados para determinar a distribuição e a frequência de cada um dos possíveis haplótipos. As 79 amostras coletadas em campo foram amplificadas por PCR com primers específicos das regiões espaçadores ITS e dos genes 18S, 28S e 5,8S. Posteriormente as regiões amplificadas foram sequenciadas pelo método Sanger. Para complementar as análises foram adicionadas sequências disponíveis no NCBI, totalizando uma matriz de dados de 263 amostras. As árvores geradas, a partir de análises filogenéticas Bayesiana, Máxima Verossimilhança e Neighbour-Joining, mostraram a divisão dos grupos de C. gloeosporioides e C. acutatum, possibilitando a separação da matriz em duas espécies específicas. As análises ...
Abstract: The rubber tree [Hevea brasiliensis (Wild. ex Adr. Than Juss. ) Muell - Arg] is the largest source of natural rubber, widely cultivated, and of great commercial importance due to its high production capacity. Currently the rubber trees are being attacked for various diseases, causing huge economic losses. Among them, the anthracnose, caused by Colletotrichum gloeosporioides and Colletotrichum acutatum, is in all rubber crops places of the world. These fungi causes various damage, such as injuries on leaves, branches, fruits, as well as cankers in the taping panel. Given this situation, and the high incidence of this pathogen in the rubber crop, this study aimed to identify the genetic variability of the isolates of C. gloeosporioides and C. acutatum associated to rubber crop. Phylogenetic and population tools were performed to determine the distribution and frequency of each possible haplotypes. The 79 samples collected in the field were amplified by PCR by specific primers of the ITS spacers regions and the 18S, 28S and 5.8 S genes. Subsequently, the amplified regions were sequenced by the Sanger method. Several sequences available in NCBI were added, to complement the analysis, totaling a data matrix of 263 samples. Phylogenetic analyses generated by Bayesian, Maximum Likelihood and Neighbour -Joining methods, showed the division of the C. acutatum and C. gloeosporioides groups, enabling the separation of the matrix in two specific species. The population analysis showed some very common haplotypes distributed around the world, as well as another haplotypes with very restricted distribution, such as H1 haplotype of ...
Doutor
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Werner, Stefan. "Untersuchungen zur Regulation und Bedeutung der Chitin-Synthese beim Maispathogen Colletotrichum graminicola (Ces.) Wils. (Teleomorph: Glomerella graminicola Politis) /." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965236781.
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Yu, Xuefeng. "Mass production of Colletotrichum coccodes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0017/NQ44638.pdf.
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Koomen, Irene. "Biological control of Colletotrichum gloeosporioides." Thesis, University of Kent, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278551.
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Colletotrichum gloeosporioides is the causal agent of anthracnose disease of mangoes. Infection occurs when humidity is high and rain-dispersed spores germinate and form an appressorium on immature mangoes. The infection then becomes quiescent until the fruit is harvested. On ripe fruit infection is visible as black, sunken lesions on the surface. At the pre-harvest stage, the disease is controlled with the application of a range of fungicides, and at the post-harvest stage by hot benomyl treatment. The extensive use of benomyl, both pre- and post-harvest, has resulted in the occurrence of isolates of C. gloeosporioides resistant to this fungicide. To devise an alternative strategy of disease control, the potential for biological control of anthracnose has been investigated. Potential microbial antagonists of C. gloeosporioides were isolated from blossom, leaves and fruit of mango, and screened using a series of assay techniques. In total 650 microorganisms, including bacteria, yeasts and filamentous fungi, were isolated and tested for their inhibition of growth of C. gloeosporioides on malt extract agar. Of these 650 isolates, 121 inhibited the fungus and were further tested on their ability to inhibit spore germination in vitro. Of these, 45 isolates, all bacteria and yeasts, were inoculated onto mangoes, which were artificially inoculated with C. gloeosporioides, and assessed for their potential to reduce the development of anthracnose lesions. A further selection was made, and 7 isolates were chosen to be used in a semi-commercial trial in the Philippines. This final screening procedure yielded two potential candidates for field trials, isolate 204 (identified as Bacillus cereus) and isolate 558 (identified as Pseudomonas fiuorescens). A field trial involving pre-harvest application of the biological control agent, was conducted using isolate 558. This isolate was chosen for this purpose since in in vitro experiments it significantly reduced germination of C. gloeosporioides spores. In the field trial 558 was applied in combination with nutrients and compared to treatments which had received no treatment or which had received conventional fungicide (benomyl) application. On spraying, high numbers of 558 were recorded on the leaf surface, but no reduction in post-harvest development of disease was observed. Failure of disease control was attributed to rapid death of the bacterium on the phylloplane. Inpost-harvest trials, isolates 204 and 558 were both tested in combination with different application methods, including the addition of sticker, peptone, fruit wax or a sucrose polyester. Application of 204 did not reduce disease development. Application of 558, however, did significantly reduce anthracnose development compared to the control fruit. No additional benefit was achieved by incorporating the bacteria in peptone, fruit wax or sucrose polyester. The mode of action of isolate 558 was investigated in detail. There was no evidence for parasitism taking place, or the production of volatile compounds, in the suppression of disease development. No antibiotic compounds were detected, but isolate 558 did produce a siderophore. A sharp increase in pH was also observed in culture media in which 558 was grown. Disease control may result from a combination of these two factors.
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Sierra, Hayer Juan Fernan [UNESP]. "Caracterização e controle de colletotrichum spp. em seringueira (Hevea brasiliensis)." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/97222.
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sierrahayer_jf_me_botfca.pdf: 13042883 bytes, checksum: c8c75feb8bc74ce204bc7a174adc9e95 (MD5)A cultura da seringueira [Hevea brasiliensis (Willd. ex Adr. Jussieu) Muell. Arg.] vem sendo atacada por várias doenças de importância econômica, dentre as quais está a antracnose, causada pelo fungo Colletotrichum sp. (teleomorfo: Glomerella sp.). Este fungo causa vários danos na planta como lesões nos folíolos, nos ponteiros, nos ramos, nos frutos e cancros no painel de sangria. Somente Colletotrichum gloeosporioides foi relatado como agente causal desta doença no Brasil. O presente trabalho teve como objetivo identificar isolados de Colletotrichum spp. de seringueira de diversas regiões de plantio do Estado de São Paulo. O trabalho foi conduzido em cinco fases: a) caracterização cultural, na qual foram observadas a coloração e o aspecto das culturas in vitro. Produção de conídios e taxa de crescimento em seis temperaturas (10, 15, 20, 25, 30 e 35 °C); b) caracterização morfológica, na qual foi medido comprimento, largura e observado o formato dos conídios; c) teste de patogenicidade em folíolos destacados e em discos de folíolos, com quatro isolados de seringueira e dois de citros; d) crescimento em benomyl em quatro concentrações de princípio ativo; e) Identificação molecular para culturas monospóricas e multispóricas com primers específicos para as espécies de Colletotrichum gloeosporioides e Colletotrichum acutatum e os primers ITS1 e ITS4 os quais amplificaram uma pequena região (18S) e uma grande região (28S), e estes também permitiram a amplificação da região 5.8S do rDNA e os espaçadores internos transcritos (ITS1 e ITS2), e f) testes de crescimento em meio de cultivo acrescido com fungicidas: flutriafol, tebuconazol, epoxiconazol + piradostrobina, clorotalonil + tiofonato-metílico, captana, mancozebe, carbendazim, azoxistrobina + ciproconazol e propiconazol. Neste teste foram utilizados quatro isolados de diferentes órgãos da planta...
The rubber cultivation [Hevea brasiliensis (Willd. ex Adr. Jussieu) Muell. Arg.] is being attacked by several diseases of economic importance, among which is the anthracnose; this is caused by the fungus Colletotrichum spp. (teleomorph: Glomerella spp). This fungus causes several damages in the plant such as injuries in the leaves, branches, fruits and cankers in the taping panel. Only Colletotrichum gloeosporioides was reported as the causal agent of this disease in Brazil. The aim of this study was to identify isolates of the fungus Colletotrichum spp. from rubber trees, localized in different regions of Sao Paulo state. The study was carried out by six phases: a) culture characterization, in which the color and the culture appearance were observed in vitro, conidial production and growth rate at six temperatures (10, 15, 20, 25, 30, 35 °C); b) morphological characterization, which consist of measuring the length and width, and observed the shape of the conidia; c) pathogenicity test on selected leaves and disks of leaves, with four isolates from rubber and two isolates from citrus; d) growth in fungicide benomyl at four concentrations of active ingredient; e) molecular identification for monosporic and multisporic cultures with specific primers to the species of Colletotrichum gloeosporioides and Colletotrichum acutatum and ITS1 and ITS4 primers which amplified a small region (18S) and a large region (28S), and these also allowed the amplification of 5.8S rDNA and internal transcribed spacers (ITS1 and ITS2); f) Growth tests in culture medium supplemented with fungicides: flutriafol, tebuconazole, epoxiconazole + piradostrobina, chlorothalonil + tiofonato-methyl, captan, mancozeb, carbendazim, azoxystrobin + cyproconazole and propiconazole. In this test, four isolates were used from... (Complete abstract click electronic access below)
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Giblin, Fiona Rosanna. "Avocado fruit responses to Colletotrichum gloeosporioides /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19403.pdf.
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Ahn, Byeongseok. "Enhancing biocontrol activity of Colletotrichum coccodes." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82816.
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Resistance responses of Abutilon theophrasti were investigated to determine defense mechanisms of the weed against Colletotrichum coccodes and to verify if some chemical suppression of the resistance mechanism could be exploited to enhance the virulence. Induced resistance in A. theophrasti has been confirmed in treatments with C. coccodes, benzothiadiazole, bentazon, and acifluorfen. Induction of peroxidase and phenylalanine ammonia lyase (PAL) activities in the leaves that did not contact with the inducing agents was observed after the localized stresses to the first leaf or the root of the plant with those agents. alpha-Amino-oxy acetic acid (AOA), 2-deoxy-D-glucose (DDG), mannose, oxalic acid, and analogues of oxalic acid and mannose were tested to enhance C. coccodes virulence. However, the compounds did not enhance C. coccodes virulence or affect A. theophrasti growth. Strong antifungal effects, poor inhibitory effects on plant defense mechanisms, or minor dependence of A. theophrasti on the defense mechanisms that the chemicals affected could be reasons. The efficacy of C. coccodes increased in the presence of 0.25 kg a.i. ha-1 bentazon more than when C. coccodes was applied alone, while the effect of glyphosate was minimal. Peroxidase activity was strongly induced by the treatment of C. coccodes and increased over time. PAL and activation of peroxidase was inhibited in the presence of bentazon, suggesting the synergy effect by bentazon is probably due to the suppression on the two defense-related enzymes. In conclusion, A. theophrasti exploits various biochemical and morphological types of defense mechanisms against C. coccodes infection. However, the activation of the defense responses can be suppressed or by-passed in an integrated weed management system.
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Pakela, Yolisa Patronella. "Interaction between Colletotrichum dematium and cowpea." Thesis, Pretoria: [s.n.], 2003. http://upetd.up.ac.za/thesis/available/etd-09022005-102127/.
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Moraes, Sylvia Raquel Gomes. "Infecção e colonização de Colletotrichum gloeosporioides em goiaba e infecção de Colletotrichum acutatum em folhas de citros." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-15042009-085030/.
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O objetivo do trabalho foi determinar o efeito da temperatura e período de molhamento no processo de infecção de Colletotrichum gloeosporioides e C. acutatum em goiaba e folhas de citros, respectivamente, além de evidenciar o processo de colonização de C. gloeosporioides. Para determinar o processo de infecção em diferentes combinações de temperatura e períodos de molhamento, suspensões de conídios de C. gloeosporioides foram depositadas em placas de poliestireno e incubadas sob temperaturas de 10, 15, 20, 25, 30, 35 e 40 °C, com período de molhamento de 6, 12, 24, 36 e 48 horas. Para C. acutatum, as placas foram incubadas sob temperaturas de 5, 10, 15, 20, 25, 30 e 35 °C, com períodos de molhamento de 6, 12, 24, 36 e 48 horas. In vivo, suspensões de conídios de C. gloeosporioides foram depositadas na superfície de goiabas que foram incubadas sob temperaturas de 10, 15, 20, 25 e 30 °C e períodos de molhamento de 6, 12 e 24 horas. Folhas de citros foram inoculadas com suspensões de dois isolados de C. acutatum e incubadas sob temperatura de 15, 20, 25 e 30 °C e períodos de molhamento de 12, 24 e 48 horas. Para os estudos do processo de colonização, goiabas com 110 dias após a queda das pétalas foram inoculadas e incubadas a 25 °C e períodos de molhamento de 48, 72, 96 e 120 horas. Posteriormente, frutos com 10, 35, 60 e 85 dias também foram inoculados e incubados a 25 °C por 48 horas. Para visualizar estruturas do tecido vegetal e fenóis, secções de frutos com as diferentes idades foram coradas com azul de toluidina e ACN. As temperaturas ótimas in vitro para germinação de C. gloeosporioides, apressórios formados e melanizados foram, respectivamente, 22,7, 20,6 e 23 °C. Para o isolado KLA-MGG-1 de C. acutatum foi 23,9 °C para germinação e 23,5 °C para formação de apressórios, enquanto para o isolado FSH-CLB-2 foi 21,6 °C para ambas as variáveis. Em goiaba, as temperaturas ótimas para germinação de C. gloeosporioides e formação de apressórios foram 22,4 e 23,3 °C, respectivamente. Em folhas de laranjeira, as temperaturas ótimas para os isolados KLA-MGG-1 e FSH-CLB-2 foram, respectivamente, 24,1 e 24 °C para germinação e 21,2 e 23 °C para formação de apressórios. Para folhas de limoeiro, foram 18,1 °C para germinação e 16,2 °C para formação de apressórios do isolado KLA-MGG-1. Para o isolado FSH-CLB-2, as temperaturas ótimas foram 24,4 e 23,7 °C, respectivamente. A estratégia de colonização de C. gloeosporioides foi intracelular hemibiotrófica. Em amostras com 48 h após a inoculação, foi verificado o peg de penetração. Com 72 horas, observou-se a formação da vesícula de infecção. As hifas foram observadas em amostras com 96 h após inoculação. As mesmas estruturas fúngicas alcançaram as células parenquimáticas com 120 horas após inoculação. O peg de penetração foi observado apenas em frutos com 85 e 110 dias. Estruturas do tecido vegetal e fenóis foram alterados com a idade dos frutos.The objective of this study was to determine the effect of temperature and the wetness periods in the infection process of Colletotrichum gloeosporioides and C. acutatum in guava and citrus leaves, respectively, besides evidencing the colonization process of C. gloeosporioides. To determine the infection process at different temperature and wetness periods combinations, conidial suspensions of C. gloeosporioides were deposited on polystyrene dishes and incubated at 10, 15, 20, 25, 30, 35 and 40 °C with wetness periods of 6, 12, 24, 36 and 48 h. For C. acutatum, the dishes were incubated at 5, 10, 15, 20, 25, 30 and 35 °C, with wetness periods of 6, 12, 24, 36 and 48 h. In vivo conidial suspensions of C. gloeosporioides were placed on the surface of guavas which were incubated at 10, 15, 20, 25 and 30 °C with wetness periods of 6, 12 and 24 h. The citrus leaves were inoculated with suspensions of two isolates of C. acutatum and incubated at 15, 20, 25 and 30 °C with wetness durations of 12, 24 and 48 h. For the analysis on the colonization process, physiological mature guava fruits were inoculated and incubated at 25 °C with wetness periods of 48, 72, 96 and 120 h. Afterward, fruits with 10, 35, 60 and 85 days were also inoculated and incubated at 25 °C for 48 hours. To visualize the structures of vegetal tissues and phenols, sections of fruits at different ages were colored in toluidine blue and ACN. Optical temperature for conidial germination, appressoria formation and appressoria melanization for C. gloeosporioides were, respectively, 22.7, 20.6 and 23.0 °C. For C. acutatum isolate KLA-MGG-1, they were 23.9 °C for germination and 23.5 °C for appressoria formation and for isolate FSH-CLB-2 it was 21.6 °C for both variable. In guava, the temperatures for germination of C. gloeosporioides and appressoria formation were 22.4 and 23.3 °C, respectively. In leaves of orange trees, the optimal temperatures for the isolates KLA-MGG-1 and FSH-CLB-2 were, respectively, 24.1 and 24 °C for germination and 21.2 and 23 °C for appressoria formation. In leaves of lemon trees, they were 18.1 °C for germination and 16.2 °C for appressorial production of isolate KLA-MGG-1. For isolate FSH-CLB-2, the optimal temperatures were 24.4 and 23.7 °C, respectively. The colonization strategy of C. gloeosporioides was intracellular hemibiotrophic. The penetration peg was verified in samples 48 h after inoculation. After 72 h, it was observed formation of infection vesicle. The hyphae were observed in samples 96 h after inoculation. The same fungal structures reached the parenchymal cells 120 hours after inoculation. The penetration peg was observed only in fruits with 85 and 110 days. Structures of guava tissues and phenols were changed with the fruit aging.
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Soares, Ana Raquel. "Infecção e colonização de goiabas por Colletotrichum gloeosporioides e Colletotrichum acutatum sob diferentes temperaturas e períodos de molhamento." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-17072008-154409/.
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Duas espécies de Colletotrichum podem causar antracnose em goiabas: C. gloeosporioides e C. acutatum. Apesar de ser a principal doença pós-colheita da cultura, a influência de variáveis ambientais no seu desenvolvimento é desconhecida. O objetivo do presente trabalho foi determinar a influência das variáveis ambientais no desenvolvimento in vitro e nos processos de infecção e colonização dos fungos Colletotrichum gloeosporioides e C. acutatum em goiabas. A germinação e a formação de apressórios foram determinadas sob temperaturas de 10, 15, 20, 25, 30, 35 e 40 ºC, com períodos de molhamento de 6, 12 e 24 horas, sob escuro contínuo. Nos experimentos in vivo, goiabas \"Kumagai\" e \"Pedro Sato\" foram inoculadas, por ferimento, com suspensão de conídios das duas espécies e incubadas em câmaras de crescimento a 15, 20, 25 e 30 ºC e períodos de molhamento de 6 e 24 horas. Avaliou-se a incidência de frutos doentes, o diâmetro das lesões, a taxa de progresso da doença e os períodos de incubação e latência. Nas goiabas \"Kumagai\" também foi avaliada a influência dos estádios de maturação dos frutos no progresso da doença. Não houve germinação a 40 ºC em nenhuma das duas espécies. A faixa favorável à germinação e à formação de apressórios in vitro foi de 15 a 30 ºC para C. gloeosporioides, com máximo a 25 ºC e de 20 a 25 ºC para C. acutatum, com máximo a 20 ºC. Para C. acutatum, a germinação foi mais sensível a variações no período de molhamento, sendo significativamente menor com 6 horas em relação a 12 e 24 horas. Nos experimentos in vivo, temperaturas de 25 e 30 ºC e 24 horas de molhamento foram mais favoráveis para as variáveis analisadas em goiaba \"Kumagai\". Os diâmetros máximos de lesão foram de 4,0 cm para C. gloeosporioides e 4,1 cm para C. acutatum, em frutos em ponto de colheita, incubados sob temperatura de 25 ºC. A maior incidência da doença (100%) ocorreu 10 dias após a inoculação, a 30ºC e 24 horas de molhamento. O menor período de incubação foi de 7 dias para as duas espécies, observado a 30 ºC e o menor período de latência foi de 10 e 9 dias para C. gloeosporioides e C. acutatum, respectivamente, sob temperaturas de 25 ou 30 ºC. Em goiabas \"Pedro Sato\", as temperaturas entre 20 e 30 ºC e 24 horas de molhamento foram mais favoráveis. Os diâmetros máximos de lesão foram de 3,3 cm para C. gloeosporioides e 3,2 cm para C. acutatum sob temperatura de 25 ºC. A maior incidência da doença (100%) ocorreu 10 dias após a inoculação, a 25 e 30ºC sob 6 horas de molhamento. O período de incubação foi de 7 dias para as duas espécies entre 20 e 30 ºC e o período de latência foi de 8 dias para C. gloeosporioides e 9 dias para C. acutatum sob temperaturas de 25 e 30 ºC. As condições requeridas para as duas espécies fúngicas foram semelhantes, embora o intervalo de favorabilidade seja mais amplo na goiaba \"Pedro Sato\".The main causal agents of Anthracnose in guava are Colletotrichum gloeosporioides and C. acutatum. Although anthracnose is the main postharvest disease affecting guava, little is known about the influence of environmental variables on its development. Consequently, the objective of the present study was to determine the influence of environmental factors on in vitro development and on colonization and infection processes of C. gloeosporioides and C. acutatum fungi in guava. The germination and apressorium formation were determined at temperatures of 10, 15, 20, 25, 30, 35 and 40 °C, with wetness durations of 6, 12 or 24 hours under continuous darkness. The in vivo experiments involved puncturing the skin of the Kumagai and Pedro Sato varieties of guava with a needle followed by inoculation with conidial suspensions of C. gloeosporioides and C. acutatum. Fruits were then incubated in growth chambers at temperatures of 15, 20, 25 and 30 °C with wetness duration of 6 and 24 hours. Assessments were made of the following: incidence of disease, lesion diameter, rate of disease progress, as well as incubation and latency periods. In the Kumagai variety, the influence of maturity on disease progression was also evaluated. There was no germination at 40 oC in any of the species. The germination and apressorium formation rate were rather high in the range of 15 to 30 ºC for C. gloeosporioides, with a maximum at 25 ºC and of 20 to 25 ºC for C. acutatum, with a maximum at 20 ºC. For the species C. acutatum, germination rate was more sensitive to variations in wetting periods, thus significantly smaller with 6 hours on 12 and 24 hours. Temperatures of 25 and 30 °C were found to be more favorable for the variables analyzed in the in vivo experiments of Kumagai variety. The maximum lesion diameter recorded in this variety was 4.0 cm for C. gloeosporioides and 4.1 cm for C. acutatum in harvest ready fruit that had been incubated at temperatures lower than 25 °C. The highest incidence of the disease (100%) occurred 10 days after inoculation, at 30 º C and 24 hours of wetting. The lowest incubation period for both species was 7 days at 30 °C and the lowest latency period of 9 days for C. gloeosporioides and 10 days for C. acutatum at temperatures between 25 and 30 °C. For the Pedro Sato variety, temperatures between 20 and 30 °C with a 24 hour wetness period were found to be the most favorable conditions. The maximum lesion diameter was 3.3 cm for C. gloeosporioides and 3.2 cm for C. acutatum at temperatures below 25 °C. The highest incidence of the disease (100%) occurred 10 days after inoculation, at 25 and 30 º C and 6 hours of wetting. The lowest incubation period for both species was 7 days at temperatures between 20 and 30 °C and the lowest latency period of 8 days for C. gloeosporioides and 9 days for C. acutatum at temperatures between 25 and 30 °C. In conclusion, development conditions for Colletotrichum gloeosporioides and Colletotrichum acutatum were similar, although the range of conditions favorable for the Pedro Sato variety was wider than that of the Kumagai cultivar.
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Menezes, Henrique Dantas de. "Inativação fotodinâmica de conídios dos fungos Aspergillus nidulans, Colletotrichum acutatum e Colletotrichum gloeosporioides com fotossensibilizadores fenotiazínicos e cumarínicos." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/60/60135/tde-26102012-154056/.
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O tratamento fotodinâmico antifúngico (APDT) é um método promissor que combina um fotossensibilizador não tóxico (FS), oxigênio e luz visível para provocar a morte seletiva das células microbianas. O desenvolvimento do APDT depende da identificação de FS que sejam eficazes para as diferentes espécies de patógenos. No presente estudo, as suscetibilidades, in vitro, de conídios de Colletotrichum acutatum, C. gloeosporioides (ambas são espécies fitopatogênicas) e Aspergillus nidulans ao APDT com quatro FS fenotiazínicos [azul de metileno (MB), novo azul de metileno N (NMBN), azul de toluidina O (TBO) e o novo fenotiazínico pentacíclico S137 (S137)] em combinação com a luz vermelha, foram investigadas. Nós também avaliamos a suscetibilidade dos conídios de C. acutatum e A. nidulans ao APDT com o psoraleno 8-metóxipsoraleno (8-MOP), com duas cumarinas (7- metoxicumarina e 5,7-dimetóxicumarina) e com uma furanocumarina (isopimpinelina) em combinação com a radiação solar. Ambas as cumarinas e a furanocumarinas foram extraídas, no presente trabalho, do limão Tahiti (Citrus latifolia). Os efeitos dos tratamentos com os diferentes FS nas folhas de laranja-pera (Citrus sinensis) também foram avaliados. O NMBN e o S137 foram os fenotiazínicos mais eficazes. Os APDT com o NMBN (50 ?M) e S137 (10 ?M) e dose de luz de 25 J cm-2 resultaram na redução de aproximadamente 5 logs na sobrevivência dos conídios das três espécies. O APDT com o 8-MOP e com as cumarinas resultaram em uma redução de aproximadamente 4 logs na sobrevivência dos conídios de C. acutatum e A. nidulans. O APDT com a furanocumarina foi menos efetivo e resultou em uma redução na sobrevivência dos conídios de aproximadamente dois logs para C. acutatum e de três logs para A. nidulans. Nenhum dano nas folhas foi observado quando os FS foram colocados na superfície adaxial das folhas. Os estudos histológicos mostraram que nenhum dos FS fenotiazínicos atravessou a cutícula das folhas.Antifungal photodynamic treatment (APDT) is a promising method that combines a nontoxic photosensitizer (PS), oxygen and visible light to cause selective killing of microbial cells. The development of APDT depends on identifying effective PS for the different pathogenic species. In the present study, the in vitro susceptibilities of Colletotrichum acutatum, C. gloeosporioides (both are phytophatogenic species) and Aspergillus nidulans conidia to APDT with four phenothiazinium PS [methylene blue (MB), new methylene blue N (NMBN), toluidine blue O (TBO) and the novel pentacicyclic phenothiazinium S137 (S137)] in combination with red light were investigated. We also evaluated the susceptibilities of C. acutatum and A. nidulans conidia to APDT with the psoralen 8-methoxypsoralen (8-MOP), with two coumarins (7-methoxicoumarin and 5,7-dimethoxycoumarin) and one furanocoumarin (isopimpinelin) in combination with solar radiation. Both the coumarins and the furanocoumarin were extracted, in the present work, from Tahiti lemon (Citrus latifolia). The effects of the treatments with all the PS on Citrus sinensis leaves were also evaluated. NMBN and S137 were the more effective phenothiazinium PS. APDT with NMBN (50 ?M) and S137 (10 ?M) and light dose of 25 J cm-2 resulted in a reduction of approximately 5 logs in the survival of the conidia of the three species. APDT with 8-MOP and with the coumarins resulted in a reduction of approximately 4 logs in the survival of C. acutatum and A. nidulans conidia. APDT with the furanocumarin was less effective and resulted in the reduction of approximately 2 logs for C. acutatum and 3 logs for A. nidulans. No damages to the leaves were observed when the PS were spotted on the adaxial surface of the leaves and the plants were exposed to solar radiation. Histological studies showed that the phenothiazinium PS did not cross the leave cuticle.
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Sierra, Hayer Juan Fernan 1980. "Caracterização e controle de colletotrichum spp. em seringueira (Hevea brasiliensis) /." Botucatu : [s.n.], 2010. http://hdl.handle.net/11449/97222.
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Orientador: Edson Luiz FurtadoBanca: Cesar Junior Bueno
Banca: Marli de Fátima Stradioto Papa
Resumo: A cultura da seringueira [Hevea brasiliensis (Willd. ex Adr. Jussieu) Muell. Arg.] vem sendo atacada por várias doenças de importância econômica, dentre as quais está a antracnose, causada pelo fungo Colletotrichum sp. (teleomorfo: Glomerella sp.). Este fungo causa vários danos na planta como lesões nos folíolos, nos ponteiros, nos ramos, nos frutos e cancros no painel de sangria. Somente Colletotrichum gloeosporioides foi relatado como agente causal desta doença no Brasil. O presente trabalho teve como objetivo identificar isolados de Colletotrichum spp. de seringueira de diversas regiões de plantio do Estado de São Paulo. O trabalho foi conduzido em cinco fases: a) caracterização cultural, na qual foram observadas a coloração e o aspecto das culturas in vitro. Produção de conídios e taxa de crescimento em seis temperaturas (10, 15, 20, 25, 30 e 35 °C); b) caracterização morfológica, na qual foi medido comprimento, largura e observado o formato dos conídios; c) teste de patogenicidade em folíolos destacados e em discos de folíolos, com quatro isolados de seringueira e dois de citros; d) crescimento em benomyl em quatro concentrações de princípio ativo; e) Identificação molecular para culturas monospóricas e multispóricas com primers específicos para as espécies de Colletotrichum gloeosporioides e Colletotrichum acutatum e os primers ITS1 e ITS4 os quais amplificaram uma pequena região (18S) e uma grande região (28S), e estes também permitiram a amplificação da região 5.8S do rDNA e os espaçadores internos transcritos (ITS1 e ITS2), e f) testes de crescimento em meio de cultivo acrescido com fungicidas: flutriafol, tebuconazol, epoxiconazol + piradostrobina, clorotalonil + tiofonato-metílico, captana, mancozebe, carbendazim, azoxistrobina + ciproconazol e propiconazol. Neste teste foram utilizados quatro isolados de diferentes órgãos da planta... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The rubber cultivation [Hevea brasiliensis (Willd. ex Adr. Jussieu) Muell. Arg.] is being attacked by several diseases of economic importance, among which is the anthracnose; this is caused by the fungus Colletotrichum spp. (teleomorph: Glomerella spp). This fungus causes several damages in the plant such as injuries in the leaves, branches, fruits and cankers in the taping panel. Only Colletotrichum gloeosporioides was reported as the causal agent of this disease in Brazil. The aim of this study was to identify isolates of the fungus Colletotrichum spp. from rubber trees, localized in different regions of Sao Paulo state. The study was carried out by six phases: a) culture characterization, in which the color and the culture appearance were observed in vitro, conidial production and growth rate at six temperatures (10, 15, 20, 25, 30, 35 °C); b) morphological characterization, which consist of measuring the length and width, and observed the shape of the conidia; c) pathogenicity test on selected leaves and disks of leaves, with four isolates from rubber and two isolates from citrus; d) growth in fungicide benomyl at four concentrations of active ingredient; e) molecular identification for monosporic and multisporic cultures with specific primers to the species of Colletotrichum gloeosporioides and Colletotrichum acutatum and ITS1 and ITS4 primers which amplified a small region (18S) and a large region (28S), and these also allowed the amplification of 5.8S rDNA and internal transcribed spacers (ITS1 and ITS2); f) Growth tests in culture medium supplemented with fungicides: flutriafol, tebuconazole, epoxiconazole + piradostrobina, chlorothalonil + tiofonato-methyl, captan, mancozeb, carbendazim, azoxystrobin + cyproconazole and propiconazole. In this test, four isolates were used from... (Complete abstract click electronic access below)
Mestre
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Saad, Fadia. "Formulation of Colletotrichum coccodes as a bioherbicide." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41025.
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Colletotrichum coccodes (Wallr.) Hughes, a foliar pathogen of velvetleaf, is being developed as a bioherbicide. Formulation of living organisms for use as pest control products presents unique problems. This research has achieved the development of an adequate formulation of the pathogen by using kaolin clay or talcum powder (1:2.79 wt/wt) as the fillers to dry conidia. Formulated C. coccodes conidia stored at 4, 30C, or at room temperature in bags permeable to oxygen remained viable and able to infect velvetleaf plants at least six months in storage. Various reported germination stimulants increased germination of formulated conidia, although not significantly, whereas increasing concentrations of cutin resulted in subsequent decreases in germination and appressoria formation of fresh as well as formulated conidia. In controlled environment experiments, 14 day-old velvetleaf seedlings were severely diseased when stearic or oleic acids were added to conidia formulated in kaolin clay or talcum powder, respectively. Combinations of germination stimulants, cutinase and/or pectinase inducers did not significantly increase germination and appressoria formation of C. coccodes conidia. Germination of fresh and formulated conidia increased, although not significantly, with the addition of 1% sucrose.
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Homer, Karen Ann. "Anthranilate and conidial germination in colletotrichum musae." Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315600.
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Mila, Grahovac. "Biološko suzbijanje Colletotrichum spp. parazitauskladištenih plodova jabuke." Phd thesis, Univerzitet u Novom Sadu, Poljoprivredni fakultet u Novom Sadu, 2014. https://www.cris.uns.ac.rs/record.jsf?recordId=85566&source=NDLTD&language=en.
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Colletotrichum spp. su značajni prouzrokovači bolesti biljaka u svetu i u našoj zemlji, u polju i u skladištu. Na plodovima jabuke prisutne su dve vrste ovog roda, C. acutatum i C. gloeosporioides. Pomenute vrste uzrokuju ekonomski značajne gubitke posle berbe plodova jabuke, tokom skladištenja, transporta i plasmana na tržište. Nedoumice sa kojima se naučna javnost suočava kada je u pitanju ovaj rod jeste precizno utvrđivanje sistematske pozicije i definisanje vrsta i nižih kategorija. Klasične fitopatološke metode ne omogućavaju preciznuividentifikaciju do nivoa vrste. Otuda su molekularni pristupi sve zastupljeniji u identifikaciji Colletotrichum spp. U suzbijanju skladišnih patogena pretežno se primenjuju hemijski fungicidi. Zbog nepovoljnih toksikoloških svojstava i pojave rezistentnosti, primena hemijskih fungicida se sve više redukuje, a njihova upotreba posle berbe plodova zabranjena je u većini zemalja. Stoga, za održivi razvoj poljoprivredne proizvodnje neophodna su istraživanja usmerena ka otkrivanju mikroorganizama i prirodno sintetisanih materija koje imaju potencijala za primenu u biološkoj zaštiti.Cilj ovog rada je da se utvrdi zastupljenost Colletotrichum spp. na uskladištenim plodovima jabuke u R. Srbiji, kao i pouzdanost klasičnih i molekularnih metoda za njihovu identifikaciju do nivoa vrste i nižih kategorija. Utvrđivanje filogenetske pozicije i genetičke udaljenosti izolata je takođe svrstano u ciljeve istraživanja. Nadalje, cilj je i da se izdvoje mikroorganizami i etarska ulja koja ispoljavaju antifungalno delovanje na Colletotrichum spp. Zatim, da se za mikroorganizam sa najizraženijim antifungalnim delovanjem definišu uslovi kultivacije (sastav hranljive podloge i trajanje) koji maksimizuju njegovu antifungalnu aktivnost i utvrdi način njegovog delovanja.Utvrđeno je da su Colletotrichum spp. redovno prisutni na uskladištenim plodovima jabuke u Vojvodini i delovima zapadne, centralne i jugoistočne Srbije i da je njihova zastupljenost u odnosu na druge fitopatogene gljive 7,8-10%. Zbog osetljivosti C. gloeosporioides na niske temperature, C. acutatum postaje sve dominantnija vrsta ovog roda na uskladištenim plodovima jabuke. Razlikovanje C. acutatum i C. gloeosporioides je moguće na osnovu fenotipskih karakteristika kolonija (u slučaju hromogenih izolata C. acutatum), dužine konidija, rasta kolonija na 5 i 35°C i brzine rasta kolonija na različitim podlogama. Oblik i širina konidija i optimalna temperatura rasta su nedovoljno pouzdani kriterijumi za identifikaciju do nivoa vrste. PCR metodom uz primenu prajmera specifičnih za vrstu uspešno se identifikuju C. acutatum i C. gloeosporioides. Primenom univerzalnih prajmera ITS1 i ITS4 amplifikuju se rDNK-ITS sekvence ovih izolata. Analizom sekvenci izrađuju se filogenetska stabla visoke stabilnosti i jasno razdvajaju C. acutatum i C. gloeosporioides, a u okviru C. acutatum se odvajaju nehromogeni i hromogeni izolati. S. hygroscopicus, S. aureus, B. cereus, P. aeruginosa i B. subtilis sojevi N146, ST 1/III, Č13 i QST 713 ispoljavaju antifungalnu aktivnost na Colletotrichum spp. in vitro i in vivo. S. hygroscopicus obezbeđuje zaštitu plodova na nivou sa hemijskim fungicidima (trifloksistrobin, boskalid+piraklostrobin, pirimetanil+flukvinkonazol, kaptan). Kultivacijom S. hygroscopicus u podlozi sa 15,07 g/l glicerola, 5,28 g/l ekstrakta kvasca i 0,81 g/l fosfata, uvtrajanju 3-4 dana, postiže se maksimalno antifungalno delovanje na Colletotrichum spp. Antifungalno delovanje S. hygroscopicus zasnovano je na produkciji ekstracelularnih, termostabilnih metabolita. Dvomesečno skladištenje trtiranih plodova na 2±0,5°C ne slabi antifungalno delovanje S. hygroscopicus. Etarska ulja origana i timijana ispoljavaju snažno inhibitorno delovanje na Colletotrichum spp.Colletotrichum spp. are significant plant pathogens worldwide in field, as well as on stored fruits. Two species of this genera, C. acutatum and C. gloeosporioides, can occur on apple fruits. The species cause significant economic losses on apple fruits after harvest, during storage, transport and marketing. Scientific community faces confusion in defining precise systematic position of this genera, as well as in identification to the species level and lower categories. Conventionalviiiphytopathological methods do not provide precise identification to the species level. Thus, molecular approaches are taking the lead in Colletotrichum spp. identification. Post-harvest pathogens are mainly managed by chemical fungicides. Due to adverse toxicological properties and resistance occurrence, use of chemical fungicides is being reduced, and their application after harvest is prohibited in most countries. Therefore, studies regarding detection of microorganisms and naturally synthetized substances with a potential for application in biological control are necessary for sustainable development of agriculture.The aim of this study was to determine frequency of Colletotrichum spp. on stored apple fruits in the Republic of Serbia as well as reliability of conventional and molecular methods in their identification to the species level and lower categories. Determination of phylogenetic position and molecular distance of the isolates were also set as investigation goals. The aim was also to determine microorganisms and essential oils with antifungal activity against Colletotrichum spp. Defining of cultivation conditions (nutrient medium composition and duration) for the microorganism with the most pronounced antifungal activity which maximize its activity and defining its mode of action were also set as goals.It was found that Colletotrichum spp. are commonly present on stored apple fruits in Vojvodina Province and in western, central and southeastern parts of Serbia with a share of 7.8-10% among other phytopathogenic fungi. Due to susceptibility of C. gloeosporioides to low temperatures, C. acutatum is becoming dominant species of this genus on stored apple fruits. Discrimination between C. acutatum and C. gloeosporioides is possible on the basis of phenotypic characteristics of colony (in the case of chromogenus isolates of C. acutatum), conidium length, colony growth at 5 and 35°C and colony growth rate on different media. Conidium shape and width and optimal growth temperature are insufficient criteria for identification to the species level. PCR method using species-specific primers is reliable for identification of C. acutatum and C. gloeosporioides. rDNK-ITS sequences of the isolates can be successfully amplified with universal primers, ITS1 and ITS4. Analyses of the sequences alow construction of highly stable phylogenetic trees with distinctively separated C. acutatum and C. gloeosporioides clades, and also additional clades of non-chromogenum and chromogenum C. acutatum isolates. S. hygroscopicus, S. aureus, B. cereus, P. aeruginosa and B. subtilis strains N146, ST 1/III, Č13 and QSTix713 exhibit antifungal activity against Colletotrichum spp. in vitro and in vivo. S. hygroscopicus ensures fruit protection at the same level as chemical fungicides (trifloxistrobin, boscalid+pyraclostrobine, pyrimethanil+flukvinconazol, captan). Cultivation of S. hygroscopicus in the medium with 15.07 g/l glycerol, 5.28 g/l yeast extract and 0.81 g/l phosphates, for 3-4 days, ensures maximal antifungal activity against Colletotrichum spp. Antifungal activity of S. hygroscopicus is based on production of extracelular, thermostable metabolites. Two-month storage of treated apple fruits at 2±0.5°C does not reduce antifungal activity of S. hygroscopicus. Oregano and thyme essential oils exhibit strong inhibitory effects on Colletotrichum
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Jeske, Małgorzata. "Badania nad Colletotrichum gloeosporioides - sprawcą antraknozy łubinu." Rozprawa doktorska, [Nakł.aut.], 2004. http://dlibra.utp.edu.pl/Content/158.
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Celem podjętych badań było: 1) określenie źródła infekcji pierwotnej patogena; 2) określenie zakresu roślin mogących być żywicielami izolatów Colletotrichum gloeosporioides pochodzących z łubinu; 3) określenie dynamiki rozwoju choroby w zależności od temperatury powietrza. Badano możliwości ograniczenia występowania patogena poprzez: 1) biologicznej ochrony łubinów z wykorzystaniem grzybów z rodzaju Trichoderma i Gliocladium oraz preparatów Biosept; 2) wybranych zabiegów agrotechnicznych (ich wpływ na występowanie patogena w kolejnych fazach rozwojowych rośliny); 3) ocenę podatności kilkunastu odmian i rodów łubinu żółtego i wąskolistnego
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Belmino, Claudia Sponholz. "Resistência do feijão-caupi a Colletotrichum truncatum." Universidade Federal de Viçosa, 2004. http://www.locus.ufv.br/handle/123456789/10176.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Os objetivos Colletotrichum deste truncatum de trabalho plantas foram: de i) obter isolados de feijão-caupi e testar sua patogenicidade; ii) estudar a relação entre a concentração de inóculo, o tempo de molhamento foliar e a idade das plantas de feijão-caupi no desenvolvimento da mancha-café causada por C. truncatum; iii) identificar genótipos de feijão-caupi com resistência à mancha-café; iv) quantificar os componentes epidemiológicos da resistência do feijão-caupi à mancha-café. Foram obtidos isolados de C. truncatum de diferentes regiões produtoras de feijão-caupi. O isolado BGR, obtido de Baixa Grande do Ribeiro-PI foi selecionado para os ensaios de resistência por ser o que esporulou abundantemente em meio de cultura BDA. Os isolados de C. truncatum obtidos de feijão-caupi e de soja foram igualmente patogênicos a ambas as culturas. A concentração do inóculo de 10 6 conídios/mL, incubação das plantas, após a inoculação, sob período de molhamento foliar de 48 horas e inoculação das plantas com três semanas de idade, foram as condições ideais para o desenvolvimento da doença. No ensaio de campo em José de Freitas-PI destacaram-se três genótipos classificados como imunes (AR-87- 435, IT89KD-260 e Sanzi-Sambili) e cinco altamente resistentes (TE97-309G-2, MNC99-548F-1, MNC99-542F-7, MNC99-537F-14 e MNC99-537F- 1). No campo em Teresina-PI, nenhum genótipo foi imune e quatro foram altamente resistentes (AR-87-435, IT91K-118-2, IT93K-452-1 e MNC99- 537F-14). Em casa de vegetação detectaram-se 18 genótipos imunes e 29 altamente resistentes. Não houve correlação entre a severidade da mancha- café e a produção de grãos. Vários genótipos foram considerados resistentes e podem ser utilizados como fontes de resistência à mancha-café nos programas de melhoramento de feijão-caupi. Analisando-se o comportamento de cada genótipo, nas diferentes condições testadas, destacaram-se: MNC99-537F-14, Sanzi-Sanbili, MNC99-548F-1, MNC99- 541F-18, TE97-309G-9, BR14-Mulato, Urubuquara-113, TE97-309G-10, TE97309G-13, MNC99-508G-2, MNC99-518G-1, MNC99541F-21, Vita-3, TE97-321G-3, MNC 99-537F-9, IT81D-1228-14, TE97-411-1F-9, TE97-411- 1F-16, MNC99-537F-7, MNC99-552F-1, IT98K-1101-5, MNC99-537F-4, MNC99-541F-6, IT93K-452-1, IT91K-118-2 e AR-87-435. A severidade da doença foi o componente epidemiológico que melhor discriminou os genótipos de feijão-caupi quanto às reações de resistência a C. truncatum, os demais componentes usados não foram eficientes. A resistência do cultivar BR14-Mulato (testemunha resistente) caracterizou-se por um maior período latente (PL), reduzido número de lesões com acérvulos (NLA) e grau de severidade e menor valor de área abaixo da curva de progresso da doença (AACPD). O cultivar BR3-Tracuateua (testemunha suscetível) apresentou menor período de incubação (PI) e PL, maior AACPD e grau de severidade.
The objectives of this work were: i) to obtain isolates of Colletotrichum truncatum from cowpea plants and to test their pathogenicity ii) to study the relationship among the inoculum concentration, the dew period and the cowpea plants' age for disease development; iii) to identify cowpea genotypes resistant to C. truncatum; iv) to quantify the epidemic components of the cowpea resistance to C. truncatum. Colletotrichum truncatum from different cowpea production areas were isolated. The BGR isolated, obtained from Baixa Grande do Ribeiro-PI, was selected to be studied due to its better sporulation in BDA culture medium. The C. truncatum isolates from cowpea and soybean were equally pathogenic to both crops. Three weeks of age, 10 6 conidium/mL and 48 hours of dew were the ideal conditions of dew period, conidial concentration and cowpea plants' age for disease development. In a cultivated cowpea field, in José de Freitas- PI, three immune (AR-87-435, IT89KD-260 and Sanzi-Sambili) and five highly resistant (TE97-309G-2, MNC99-548F-1, MNC99-542F-7, MNC99- 537F-14 and MNC99-537F-1) genotypes stood out. In the Teresina-PI field, four genotypes were highly resistant (AR-87-435, IT91K-118-2, IT93K-452-1 and MNC99-537F-14). Under greenhouse conditions 18 immune and 29 highly resistant genotypes were observed. No correlation was found among the disease severity and grain production. Several genotypes by being considered resistant can be used as resistance sources to C. truncatum in the cowpea improvement programs. For most of the environments and evaluated traits the genotypes MNC99-537F-14, Sanzi-Sanbili, MNC99- 548F-1, MNC99-541F-18, TE97-309G-9, BR14-Mulato, Urubuquara-113, TE97-309G-10, TE97309G-13, MNC99-508G-2, MNC99-518G-1, MNC99541F-21, Vita-3, TE97-321G-3, MNC 99-537F-9, IT81D-1228-14, TE97-411-1F-9, TE97-411-1F-16, MNC99-537F-7, MNC99-552F-1, IT98K- 1101-5, MNC99-537F-4, MNC99-541F-6, IT93K-452-1, IT91K-118-2 and AR- 87-435 stood out. The disease severity was an efficient epidemic component to discriminate the resistance reaction of cowpea genotypes to C. truncatum but others used components had low efficiency. The BR14-Mulato genotype resistance was characterized by a higher latent period (LP), reduced number of lesions with acervulus (NLA), severity and area below the disease progress curve (ABDPC). The susceptible BR3-Tracuateua genotype showed lower incubation period and lower LP, higher ABDPC and severity degree.
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Dudienas, Christina. "Caracterização morfológica, auxanográfica e patogênica de Colletotrichum gossypii South. e Colletotrichum gossypii - South. var. Cephalosporioides Costa e Fraga JR." Universidade de São Paulo, 1990. http://teses.usp.br/teses/disponiveis/11/11135/tde-20181127-155520/.
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Foram realizadas comparacões morfológicas auxanográficas e patogênicas entre Colletotrichum gossypii e Colletotrichum gossypii var. Cephalosporioides. No aspecto morfológico foram estudados: o número de núcleos nos conídios, a morfologia de apressórios e o tamanho dos conídios. Quanto à auxanográfia foram estudados os requerimentos nutricionais. A patogenicidade foi avaliada em maçãs destacadas e em plântulas de dois cultivares de algodoeiro: Nu-15 (suscetível a ramulose) e IAC-17 (mais resistente a ramulose), através da inoculação dos fungos. Ambos fungos apresentam conídios uninucleados e apressórios morfologicamente semelhantes. Quanto ao tamanho de conídios os fungos são diferentes. O agente da ramulose pode apresentar conídios de comprimento maior que 16 µm enquanto que todos os conídios do agente da antracnose são menores que 16 µm. Também auxanograficamente os dois fungos são diferentes: o colletotrichum causador da ramulose e deficiente em asparagina ou ácido aspártico, enquanto que o causador da antracnose e auxoautotrófico para fatores de crescimento. Quanto a patogenicidade em maçãs destacadas de IAC-17 e em plântulas de Nu-15 e IAC-17 os fungos comportaram-se de maneira semelhante. Em maçãs destacadas do cultivar Nu-15 o fungo causador da antracnose foi mais patogênico que o causador da ramuloseComparaisons among Colletotrichum gossypii and Colletotrichum gossypii var. cephalosporioides cultures in the morphological, auxanographic and pathogenic aspects were perfomed. The number of nuclei in the conidia, the morphology of the apressoria and the size of the conidia were evaluated in the morphological aspect. Nutritional requirements were studied in the auxanographic aspect. The pathogenicity was evaluated on detached bolls and seedlings of two cultivars of cotton plant: Nu-15 and IAC-17. Conidia of both fungi are uninucleated and the morphology of their appressoria is similar. Regarding the size of the conidia the fungi are different. The fungus responsible for the ramulosis can have conidia with a lenght larger than 16 µm while all the others conidia from the agent that produces anthracnosis are smoller than 16 µm. Auxanographically the two fungi are also different: The fungus responsible for the ramulosis is deficient in asparagin or aspartic acid, while the responsible for the anthracnosis is auxoautotrophic for gowth factors. The fungi were similar in pathogenicity in detached bolls of the IAC-17 and seedlings of Nu-15 and IAC-17 of cotton. The fungi were different in pathogenecity in detached bolls of Nu-15. The fungus responsible for the anthracnosis was more pathogenic than the responsible for the ramulosis in this cultivar
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Gonçalves, Amanda Emy. "Determinação de grupos de compatibilidade vegetativa e formação de tubos de anastomase conidial de colletotrichum spp. da macieira." reponame:Repositório Institucional da UFSC, 2014. https://repositorio.ufsc.br/xmlui/handle/123456789/129423.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Recursos Genéticos Vegetais, Florianópolis, 2014Made available in DSpace on 2015-02-05T21:04:35Z (GMT). No. of bitstreams: 1 328845.pdf: 3297142 bytes, checksum: 27a2f1115c660c9e8bfe3202b21ce437 (MD5) Previous issue date: 2014
A Podridão Amarga (PA) e a Mancha Foliar de Glomerella (MFG) estão entre as doenças de maior importância na cultura da macieira, pelo rápido progresso dos sintomas e elevada susceptibilidade da cultivar "Gala", uma das mais consumidas no mundo. O presente trabalho objetivou determinar os grupos de compatibilidade vegetativa (GCVs) de isolados brasileiros e uruguaios de Colletotrichum spp. de PA e MFG e monitorar a formação de tubos de anastomose conidial (TACs) in vitro e in vivo. OsGCVs foram determinados pelo pareamento em Meio Mínimo (MM) de mutantes defectivos na via de assimilação de nitrogênio. Os mutantes foram gerados em meio BDA+KClO3 e mantidos em MM. Os isolados foram classificados em mesmo GCV quando seu pareamento resultou na formação de heterocárion. Isolados de complexos ou espécies diferentes nunca perteceram ao mesmo GCV. Somente um isolado brasileiro de MFG foi incluido em mesmo GCV que isolados uruguaios de fruto Quatro e nove grupos foram encontrados dentre os isolados uruguaios e brasileiros, respectivamente. Em três GCVs, foram incluidos tanto isolados de PA quanto de MFG. Para monitorar o desenvolvimento de TACs e estruturas pré-infectivas, distribuiram-se gotas de 10 e de 20µL de supensão conidial (1x106 conídios/mL) sobre lâminas de poliestireno e superfície de folhas destacadas de macieira. O desenvolvimento foi examinado microscopicamente a cada duas horas de incubação a 25°C,entre 14 e 24h e após 48h, sobre poliestireno e folhas destacadas, respectivamente. O percentual e tempo de máxima germinação, formação e melanização de apressórios foram avaliados. Os TACs foram quantificados e categorizados conforme a conexão em três tipos: tubo-tubo(t-t), tubo-conídio (t-c) e conídio-conídio (c-c). Isolados de Colletotrichum gloeosporioides apresentaram elevada germinação e formação mais precoce de apressórios melanizados. As conexões do tipot-t foram encontradas em menor frequência, para todos os isolados testados. As conexões do tipo c-c foram as mais frequentes em isolados de Colletotrichum acutatum. Dentres todos os isolados analisados, os que apresentaram maior percentual de conexões t-t, também formaram mais t-c. Isolados de Colletotrichum fragariae e C. gloeosporioides de folha nunca desenvolveram TACs sobre poliestireno ou folhas destacadas. Aqueles que formaram TACs sobre poliestireno também o fizeram sobre a superfície do hospedeiro. Foram observados vários núcleos através dos TACs e alguns conídios com nenhum e mais de um núcleo. Em geral, populações de Colletotrichum spp. do Brasil e do Uruguai foram aparentemente distintas, sugerindo que estas mantiveram-se separadas. Os processos de formação de TACs e apressórios parecem ser antagônicos. O desenvolvimento de TACs é um processo comum para C. gloeosporioides de frutos e C. acutatum. A possível contribuição dos TACs para aumento da variabilidade de Colletotrichum spp. é discutida.
Abstract: Bitter Rot (BR) and Glomerella leaf spot (GLS) are amongst the major apple diseases, due to the fast progress of symptoms and high susceptibility of the cultivar "Gala", one of most worldwide consumed. The present study aimed to determinate the vegetative compatibility groups of brazilian and uruguayan strains of Colletotrichum spp causing BR and GLS as well as to monitor the development of conidial anastomosis tubes (CATs) in vivo and in vitro. VCGs were determined by pairing mutants defective in nitrogen assimilation pathway on Minimal Medium (MM). Mutants were generated on PDA+ KClO3 medium and kept on MM. Strains were classified in same VCG when pairing led to heterokaryon formation. Strains of different complexes or species never belonged to the same VCG. Only one GLS-brazilian strain was includedin the VCG of fruit uruguayan strains. Four and nine groups were found among uruguayan and brazilian strains, respectively. In three VCGs, both PA and MFG strains were included. In order to monitor the development of CATs and pre-infective structures, drops of 10 and 20 µL of conidial suspension (1x106 conídios/mL) were distributed on polystyrene slides and detached apple leaves surfaces. The development was microscopically examined at every two hours of incubation at 25°C, from 14 to 24h and at 48h, on polystyrene and detached leaves, respectively. Percentage and time of maximum germination, apressoria development and melanization were evaluated. CATs were quantified and categorized into three types, according to the kind of connections: tube-tube (t-t),tube-conidium (t-c) and conidium-conidium (c-c). Strains of Colletotrichum gloeosporioides showed a high percentage of germination and early formation of melanized appressoria. The t-t connections were less frequent for all strains. The c-c connections were the most frequent type for Colletotrichum acutatum strains. Among all tested strains, those showing a higher percentage of t-t- connections, also formed more t-c. Strains of Colletotrichum fragariae and C. gloeosporiodes from leaves never developed CATs, neither on polystyrene nor on detached leaves.Those that formed CATs on polystyrene also did it on host surface. Many nuclei were observed through CATs, such as many conidia with none and more than one nucleus. Generally, populations of Colletotrichum spp. from Brazil and Uruguay were apparently distinct, suggesting that they were kept isolated. Appressoria melanization and CATs development seem to be antagonist processes. Formation of CATs is a common processin C. gloeosporioides from fruits and C. acutatum. The possible contribution of CATS and its consequence for increasing variability in Colletotrichum ssp. is discussed.
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Wernitz, Marcus. "Isolierung des Proteinkinasegenes snf1 aus Colletotrichum graminicola und ihre Bedeutung für die Pathogenese." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=970402562.
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Ingram, Jason Timothy. "Spread of Colletotrichum coccodes from infected potato seed tubers and effect of fungicides on stem infection." Pullman, Wash. : Washington State University, 2008. http://www.dissertations.wsu.edu/Thesis/Fall2008/j_ingram_112108.pdf.
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Thesis (M.S. in plant pathology)--Washington State University, December 2008.Title from PDF title page (viewed on Dec. 23, 2008). "Department of Plant Pathology." Includes bibliographical references.
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Ariss, Jennifer J. "Pathological factors affecting persistence in alfalfa with emphasis on diseases incited by Fusarium and Colletotrichum species." Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1117417525.
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Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains xiii, 118 p.; also includes graphics Includes bibliographical references (p. 114-118). Available online via OhioLINK's ETD Center
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Vedovatto, Felipe. "Silício no controle de Colletotrichum lindemuthianum em feijoeiro." Universidade Federal de Santa Maria, 2017. http://repositorio.ufsm.br/handle/1/11642.
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The bean plant anthracnose is caused by fungus Colletotrichum lindemuthianum (Sacc& Magnus) Scribner, which is considered one of the main diseases that attacks the culture, which might cause losses and final productivity decrease and one of the most used alternative of control is the chemical and genetic induction of resistance. The use of silicon in agriculture presents many benefits, such as: decrease of toxicity by metals, relief of saline stress and lack of water, increase of resistance to strong winds, increase of resistance to pathogens and insects, among others. Thus, the present paper has the aim of evaluating the effect of silicon as inductor of resistance to anthracnose in bean plant, by using different sources in the seeds’ coating. It was used four sources of silicon: ash of carbonized rice hull, dust of rock commercial product Potenccy® , the commercial product Supa Sílica, Agrichem® and the commercial product Silicon SiO2, Rigrantec®. It was conducted two experiments: in experiment 1 it was tested the silicon sources applied in seeds of culture IPR Graúna, susceptible to anthracnose, through sanitary and physiological evaluation of seeds and it was carried out the histological analysis of seedlings and tegument of the seeds to detect the presence of silicon. The silicon source which presented the best answers to the anthracnose control, in experiment 1, was used in experiment 2, that was performed in the field, with two cultures of bean susceptible to anthracnose (IPR Graúna and IPR Uirapuru), where it was assessed the emergency and symptoms in the seedlings. It was possible to identify silicates in the primary leaves of bean seedlings, deriving from silicon source Silicon SiO2, Rigrantec®. The application of silicon reduces the negative effect of inoculation with Colletotrichum lindemuthianum in bean seeds.A antracnose do feijoeiro é causada pelo fungo Colletotrichum lindemuthianum (Sacc & Magnus) Scribner, sendo considerada uma das principais doenças que atacam a cultura, podendo ocasionar perdas e diminuição da produtividade final e uma das alternativas de controle mais utilizadas é a indução química e genética de resistência. O uso do silício na agricultura apresenta vários benefícios, tais como: diminuição de toxidez por metais, alívio do estresse salino e da falta de água, aumento da resistência a ventos fortes, aumento da resistência a patógenos e insetos, entre outros. Diante disso, o presente trabalho tem como objetivo avaliar o efeito do silício como indutor de resistência à antracnose do feijoeiro, utilizando diferentes fontes no recobrimento de sementes. Foram utilizadas quatro fontes de silício: cinza de casca de arroz carbonizada, pó de rocha produto comercial Potenccy®, o produto comercial Supa Sílica, Agrichem® e o produto comercial Silicon SiO2, Rigrantec®. Foram conduzidos dois experimentos: no experimento 1 foram testadas as fontes de silício aplicadas em sementes da cultivar IPR Graúna, suscetível a antracnose, através da avaliação sanitária e fisiológica das sementes, e foi realizada a análise histológica das plântulas e do tegumento das sementes para detectar a presença de silício. A fonte de silício que apresentou as melhores respostas para o controle da antracnose, no experimento 1, foi utilizada no experimento 2, que foi realizado em campo, com duas cultivares de feijão suscetíveis a antracnose (IPR Graúna e IPR Uirapuru), onde foram avaliadas a emergência e sintomas nas plântulas. Foi possível identificar silício nas folhas primárias de plântulas de feijão, somente para o tratamento com silício oriundo do produto comercial Silicon SiO2, Rigrantec®. A aplicação de silício reduz efeito negativo da inoculação com Colletotrichum lindemuthianum nas sementes de feijão.
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Silva, Vagner Alves da [UNESP]. "Resposta de cultivares de milho a Colletotrichum graminicola." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/96961.
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O presente trabalho teve como objetivo avaliar genótipos de milho quanto à resistência a Colletotrichum graminicola, em condições de campo e casa de vegetação, por inoculações artificiais com isolados do patógeno obtidos de áreas de ocorrência da doença. Os experimentos foram instalados em dois locais: Fazenda experimental da FCAV/UNESP Campus Jaboticabal-SP em dezembro de 2004 e Embrapa Milho e Sorgo - CNPMS Sete Lagoas, MG, em janeiro de 2005 e em maio de 2005, em casa de vegetação do CNPMS. De acordo com os dados obtidos no experimento, existe evidência da existência de raças de Colletotrichum graminicola entre os isolados. No ensaio de Jaboticabal, os menores valores de AACPD foram observados nos genótipos BRS 3003 (híbrido triplo), seguido do BRS 2020 (híbrido duplo). Em Sete Lagoas, os menores valores de AACPD foram para os híbridos BRS 3003 e CMS 101142 (híbrido simples). Em geral, o híbrido BRS 3003 apresentou os menores valores da AACPD, sugerindo que a maior variabilidade genética (intercruzamento de três genótipos) desse material conferiu maior proteção contra o patógeno.
This research had as an objective to evaluate genotype of corn to see the resistance to Colletotrichum graminicola, in field conditions and greenhouse conditions, through artificial inoculations with isolated pathogens obtained in locations where the disease is prevelant. The research was setup in two locations: Fazenda Experimental da FCAV/Unesp Câmpus Jaboticabal - SP in December 2004 and Embrapa Milho e Sorgo/CNPMS Sete Lagoas - MG in January 2005 and may 2005 in the greenhouse of CNPMS. According to the data obtained in the experiment, there is evidence of the existence to races of Colletotrichum graminicola among the isolates. In the plots of Jaboticabal, the lowest values of AUDPC were observed in the genotypes BRS 3003 (triple hybrid), followed by BRS 2020 (double hydrid). In Sete Lagoas, the lowest values of AUDPC were from the hybrids BRS 3003 and CMS 101142 (simple hybrid). In general the hybrid BRS 3003 showed the lowest values of AUDPC, suggesting that the greater genetic variability (intercrossing of three genotypes) of this material was better protection against the pathogen.
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Reid, Patrick J. "Factors governing quiescence of Colletotrichum gloeosporioides on tomato." Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342051.
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Zakaria, Maziah. "Colletotrichum diseases of forest tree nurseries in Malaysia." Thesis, University of Bristol, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295495.
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Buddie, Alan Graham. "Systematics of colletotrichum pathogens associated with strawberry plants." Thesis, Royal Holloway, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287902.
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Species of the genus Colletotrichum Corda are responsible for many diseases of economically important crops world-wide. One particularly susceptible crop is strawberry (Fragaria spp.) on which Colletotrichum spp. cause extremely destructive anthracnose diseases, characterised by black necrotic lesions on any part of the plant. Three "species" have been implicated in the disease: C. acutatum, C. jragariae, and C. gloeosporioides. C. acutatum is considered the causal organism of strawberry blackspot in Europe and is subject to quarantine regulations within the EU; c.jragariae has only been found in the Americas and was formerly considered the sole cause of strawberry anthracnose in North America; and C. gloeosporioides is a heterogeneous "species aggregate" which has a morphological range which can encompass examples of other "species", especially C. jragariae. The absence of a reliable test for distinguishing these "species" - classical morphological approaches are unsatisfactory - led to an international multi-disciplinary project to characterise Colletotrichum pathogens of strawberry and develop diagnostic tests for individual taxa (\,,,;,,,\..c_,,\_ \:x~ t:k._ ~0). The research reported in this thesis has demonstrated the utility of a multidisciplinary approach to the systematics of Colletotrichum pathogens of strawberry. Data obtained have supported taxon groupings at different levels. The use of mtDNA provided data of two complementary types. Firstly, the NMS primers were utilised in amplification of a fragment of "species aggregate" -specific size (with three notable exceptions) from the mitochondrial small subunit rDNA. Secondly, the Hae III restriction digests of A+T-rich DNA were able to highlight groupings below the level of species aggregates. This latter method was able to distinguish the meioticallyreproducing strains of C. jragariae from anamorphic isolates and elicited two distinct subgroups in C. acutatum. PCR techniques previously described by Mills and co works and Freeman and Rodriguez were assessed for their utility and reliability. Isozyme analyses were moderately useful for taxon differentiation at an infraspecific level with the esterase systems.Study of extracellular enzyme activities using 4 MU substituted compounds was of limited diagnostic use. Additional physiological and biochemical tests did not reveal many discriminatory tests. A few tests, however, did reflect the greater vigour generally displayed by C. jragariae isolates. Utilisation of glucuronamide and growth rate on casein were two such tests. The physiological and biochemical tests were demonstrably more useful when put together with the data from EU Project colleagues and subjected to cluster analyses and ordination techniques, then when analysed as discrete tests. Colleagues in collaborating laboratories undertook a battery of tests including molecular, physiological and biochemical studies. It is appropriate to use the entire set of information obtained from the overall EU-Project in order to fully define the groups. The results reported in this thesis can stand alone, however, allowing discrimination of the taxa at several levels.
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Marques, João Paulo Rodrigues. "Podridão floral dos citros: histopatologia de Colletotrichum acutatum." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11144/tde-17092012-160523/.
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A podridão floral dos citros (PFC) é uma doença causada pelo fungo Colletotrichum acutatum responsável por causar grandes danos à produção de citros no Brasil. A doença surge apenas em botões florais com 8mm de comprimento ou maiores, levando a formação de lesões alaranjadas nas pétalas, lesões necróticas no estigma, promove a queda prematura dos frutos e a retenção do cálice e pedúnculo, sendo este último sintoma denominado estrelinha. Este trabalho tem por objetivo: observar o modo de penetração do fungo no hospedeiro Citrus sinensis Valência e os estágios posteriores da colonização, verificar se há fatores estruturais e químicos pré-formados que expliquem o porquê do fungo não conseguir infectar botões florais com menos de 8mm, caracterizar anatomicamente o sintoma estrelinha e estigmas lesionados, investigar ultraestruturalmente pétalas inoculadas, analisar se há o estabelecimento de uma infecção quiescente nos tecidos foliares, analisar grãos de pólen após a inoculação in vivo e in vitro com o fungo. Botões florais sadios, pétalas e estigmas com e sem lesões, foram submetidos às técnicas convencionais de microscopia de luz e eletrônica. Folhas e grãos de pólen foram inoculados e analisados. Foi desenvolvida uma nova técnica de coloração para tecidos vegetais infectados por fungos. A resistência dos botões florais menores que 8mm pode estar associada às barreiras químicas e estruturais pré-formadas. O ápice, nesses botões, apresenta papilas entremeadas, cristais de oxalato de cálcio no mesofilo e câmara subestomática e cavidades de óleo localizadas muito próximas umas das outras. Botões com 8mm e 12mm possuem, no ápice, papilas com arranjo frouxo, ausência de cristais e maior distanciamento entre as cavidades de óleo. No ápice da pétala, verificou-se que as células papilosas são osmóforos. No sintoma estrelinha, nota-se sob a região de abscisão do ovário a instalação de um meristema de cicatrização. A lignificação das paredes das células da medula do receptáculo e do pedúnculo floral está associada à retenção destas estruturas na planta. Nas pétalas infectadas, o C. acutatum pode penetrar intra, intercelularmente e via estômato. O fungo pode crescer de modo subcuticular e intramural e coloniza todos os tecidos da pétala. A nova técnica de coloração se mostrou muito útil nas análises histopatológicas. O fungo associa-se aos tecidos vasculares. Acérvulos ocorrem em ambas as faces das pétalas. A cutícula nos estágios mais avançados da lesão apresenta-se alterada, ou seja, ocorre a perda da ornamentação estriada e maior deposição de material lipofílico. A síntese de materiais lipofílicos envolve o retículo endoplasmático liso e rugoso e plastídios. Vesículas provenientes de dictiossomos e de corpos multivesiculares são observadas ao longo da parede celular e estão associadas ao depósito de material lipofílico na cutícula. No estigma lesionado há a formação de uma camada de proteção. O fungo apresenta quimiotropismo e cresce em direção aos grãos de pólen infectando-os 24 horas após a inoculação. Sugere-se que C. acutatum pode utilizar grãos de pólen para a sua dispersão. Após 48 horas da inoculação as folhas apresentam conídios germinados com apressórios.The postbloom fruit drop (PFD) is a disease caused by Colletotrichum acutatum responsible for causing great damage to citrus crops in Brazil. The disease appears only in flower buds 8 mm in length or greater, leading to orange lesions in petals, necrotic lesions on the stigma, promoting the young fruit drop and the retention of the calyx and peduncle, which is called buttons. In this context, this study aimed to: observe the fungus penetration mode into the host Citrus sinensis \'Valência\' and the later stages of colonization; study the presence of preformed structural and chemical factors to explain why the fungus cannot infect floral buds with less than 8 mm in length; characterize anatomically the symptom \"buttons\" and injured stigmas; investigate the ultrastructural changes in tissues of inoculated petals; analyze whether there is the establishment of a quiescent infection in leaf tissues, analyze pollen grains after inoculation in vivo and in vitro with the fungus. Healthy buds, petals and stigmas with and without lesions, were processed and analyzed using conventional light and electron microscopy techniques. Leaves and pollen grains were also inoculated and analyzed with light microscopy. It was developed a new staining method for fungal-infected plant tissues. The resistance of flower buds smaller than 8mm may be associated with preformed structural and chemical barriers. These buttons display the apex with interspersed papillae, with crystals in mesophyll and substomatic chamber and oil cavities, which are located very close to each other on the abaxial surface. In 8mm and 12mm flower buds, the papilas in the apex become weakly interspaced, the crystals are not observed and there is the increase of the distance between the oil cavities. The papillose cells are osmophores. In the symptom \"button\", it is noted in the abscission of the ovary, an installation of wound meristem. There is also the lignification in the pith of receptacle and pedicel that can be associated with the retention of these structures in the plant. In infected petals, it was found that C. acutatum can penetrate intra and intercelullar or via stomata. The fungus may grow subcuticular and intramural and colonize all tissues of petal. The new staining technique developed has proved very useful for histopathological analysis. The fungus is closely associated with vascular tissues. The acervulli occur on both surfaces of petals. The cuticle in the later stages of the lesion is altered, i.e., there is loss of striated ornamentation and increased deposition of lipophilic material. The synthesis of lipophilic materials involves rough and smooth endoplasmic reticulum and plastids. Vesicles from dictyosomes and multivesicular bodies were observed throughout the cell wall and are associated with the deposit of lipophilic material in the cuticle. There is the formation of protective layer over the stigma damaged area. The fungus shows chemotropism and grows toward the pollen infecting it 24 hours after inoculation. It is suggested that C. acutatum can use pollen grains for dispersal. After 48 hours of inoculation, the leaves have germinated conidia with appressoria.
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Silva, Vagner Alves da. "Resposta de cultivares de milho a Colletotrichum graminicola /." Jaboticabal : [s.n.], 2006. http://hdl.handle.net/11449/96961.
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Resumo: O presente trabalho teve como objetivo avaliar genótipos de milho quanto à resistência a Colletotrichum graminicola, em condições de campo e casa de vegetação, por inoculações artificiais com isolados do patógeno obtidos de áreas de ocorrência da doença. Os experimentos foram instalados em dois locais: Fazenda experimental da FCAV/UNESP Campus Jaboticabal-SP em dezembro de 2004 e Embrapa Milho e Sorgo - CNPMS Sete Lagoas, MG, em janeiro de 2005 e em maio de 2005, em casa de vegetação do CNPMS. De acordo com os dados obtidos no experimento, existe evidência da existência de raças de Colletotrichum graminicola entre os isolados. No ensaio de Jaboticabal, os menores valores de AACPD foram observados nos genótipos BRS 3003 (híbrido triplo), seguido do BRS 2020 (híbrido duplo). Em Sete Lagoas, os menores valores de AACPD foram para os híbridos BRS 3003 e CMS 101142 (híbrido simples). Em geral, o híbrido BRS 3003 apresentou os menores valores da AACPD, sugerindo que a maior variabilidade genética (intercruzamento de três genótipos) desse material conferiu maior proteção contra o patógeno.Abstract: This research had as an objective to evaluate genotype of corn to see the resistance to Colletotrichum graminicola, in field conditions and greenhouse conditions, through artificial inoculations with isolated pathogens obtained in locations where the disease is prevelant. The research was setup in two locations: Fazenda Experimental da FCAV/Unesp Câmpus Jaboticabal - SP in December 2004 and Embrapa Milho e Sorgo/CNPMS Sete Lagoas - MG in January 2005 and may 2005 in the greenhouse of CNPMS. According to the data obtained in the experiment, there is evidence of the existence to races of Colletotrichum graminicola among the isolates. In the plots of Jaboticabal, the lowest values of AUDPC were observed in the genotypes BRS 3003 (triple hybrid), followed by BRS 2020 (double hydrid). In Sete Lagoas, the lowest values of AUDPC were from the hybrids BRS 3003 and CMS 101142 (simple hybrid). In general the hybrid BRS 3003 showed the lowest values of AUDPC, suggesting that the greater genetic variability (intercrossing of three genotypes) of this material was better protection against the pathogen.
Orientador: Rita de Cássia Panizzi
Coorientador: Carlos Roberto Casela
Banca: Margarida Fumiko Ito
Banca: Ester Wickert
Mestre
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Paccola, Ednéia Aparecida de Souza. "Biologia e histopatologia de Colletotrichum sublineolum em sorgo." Universidade Estadual de Londrina. Centro de Ciências Agrárias. Programa de Pós-Graduação em Agronomia, 2006. http://www.bibliotecadigital.uel.br/document/?code=vtls000125783.
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A antracnose causada por Colletotrichum sublineolum é a mais importante doença da cultura do sorgo (Sorghum bicolor). Resultados da literatura relatam que este fungo apresenta dimorfismo conidial quando cultivado em meio sintético. Em meio sólido são produzidos conídios falcados e em meio líquido, os conídios ovais. Por serem escassas as informações sobre a biologia dos conídios ovais, este trabalho objetivou em um primeiro momento, estudar os estádios de desenvolvimento de conídios falcados e ovais de C. sublineolum sobre superfícies artificiais através da microscopia de luz e em folhas de sorgo através da microscopia eletrônica de varredura e de transmissão. E no segundo momento examinar o processo de infecção tanto do conídio falcado quanto do oval de C. sublineolum sobre cultivares de sorgo, a fim de determinar a diferença no processo de infecção entre os dois conídios e a reação dos cultivares frente à colonização dos dois tipos de conídios. Em superfícies artificiais, á semelhança dos conídios falcados, os conídios ovais se aderem, germinam e formam estruturas de infecção. A partir da germinação de conídios falcados sobre estas superfícies, são formadas hifas espessas altamente vacuoladas e em suas regiões apicais e laterais, dão origem aos conídios ovais. Conídios ovais quando inoculados sobre folhas de sorgo germinam e com 24h formam apressório, caracterizando o processo de adesão deste conídio. Acérvulos com setas contendo conídios falcados envoltos por mucilagem foram formados a partir da infecção de conídios ovais sobre a superfície foliar, caracterizando o processo infectivo deste conídio. Conídios ovais apresentam semelhanças nos eventos de pré-penetração e penetração com os conídios falcados de C. sublineolum, no entanto
no processo de infecção, os conídios falcados produzem hifas de penetração em proporção superior aos conídios ovais. Vesículas de infecção são formadas nas células epidérmicas do hospedeiro, abaixo tanto dos apressórios oriundos da germinação de conídio falcado como oval.
Conídios ovais mostraram-se infectivos e capazes de desenvolver uma série de estruturas de infecção, como por exemplo, tubo germinativo, apressório, poro de penetração, vesículas de infecção, hifas primárias e hifas secundárias, completando assim o ciclo da doença. Porém é de
extrema importância investigações mais precisas para esclarecer o verdadeiro papel biológico destes conídios no processo de estabelecimento e disseminação da doença.Anthracnose, caused by Colletotrichum sublineolum, is the most important disease of sorghum (Sorghum bicolor). Results in the literature report that this fungus exhibits conidial dimorphism when grown in synthetic media. Falcate conidia are produced in solid media whereas oval conidia are produced in liquid media. Because information on the biology of oval conidia is scarce, this research aimed to initially study the stages of development of falcate and oval conidia of C. sublineolum on artificial surfaces through light microscopy and in sorghum leaves through scanning and transmission electron microscopy. And, further on, to examine the infection process of falcate, as well as oval conidia of C. sublineolum in sorghum cultivars, to determine the difference in the infection process between the two conidia and the reaction of the cultivars in the face of colonization by both types of conidia. On artificial surfaces, similarly to falcate conidia, oval conidia adhere, germinate and form infection structures. Highly vacuolated, thick hyphae are formed from the germination of falcate conidia on these surfaces and oval conidia are formed on the apical and lateral regions of these hyphae. Oval conidia, when inoculated on sorghum leaves, germinate and with 24 hours form the appressorium, characterizing the process of adhesion of this conidium. Acervuli with setae containing falcate conidia enveloped in mucilage were formed by the infection of oval conidia on the foliar surface, characterizing the infective process of this conidium. Oval conidia exhibit similarities to falcate conidia of C. sublineolum in pre-penetration and penetration events, however, in the infection process falcate conidia produce penetration hyphae in superior proportion to oval conidia. Infection vesicles are formed in the epidermal cells of the host, under the appressoria originated from the germination of either falcate or oval conidia. Oval conidia were infective and capable of developing a series of infection structures, such as the germ tube, appressorium, penetration pore, infection vesicle, primary and secondary hyphae, thus completing the disease cycle. However, more precise investigations are extremely important to clarify the true biological role that these conidia have in the establishment and dissemination of the disease.
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Valencio, Sheila Ariana Xavier. "Microtitulação colorimétrica para avaliar a sensibilidade de Corynespora cassiicola e colletotrichum spp. a fungicidas e caracterizaçao de isolados de Colletotrichum spp." Universidade Estadual de Londrina. Centro de Ciências Agrárias. Programa de Pós-Graduação em Agronomia, 2017. http://www.bibliotecadigital.uel.br/document/?code=vtls000211673.
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Os trabalhos de monitoramento de resistência a fungicidas fornecem informações importantes para definir estratégias de manejo de doenças e evitar aplicações desnecessárias de fungicidas. O objetivo do trabalho foi: i) Avaliar a eficiência do método de microtitulação colorimétrica para determinar a sensibilidade do fungo Corynespora cassiicola e realizar o monitoramento da sensibilidade a fungicidas inibidores da desmetilação (IDM), metil benzimidazol carbamato (MBC) e inibidores da quinona oxidase (IQo); ii) Realizar a caracterização morfológica e patogenicidade de espécies do fungo Colletotrichum spp. isolados de plantas de soja e o monitoramento da sensibilidade do fungo aos fungicidas IDM, MBC e IQo. Para avaliar a eficiência do método de microtitulação colorimétrica foi comparado os valores de CE50 (concentração efetiva para reduzir metade do crescimento da colônia do fungo) para isolados de C. cassiicola, obtidos pelo método de inibição de crescimento micelial, com valores obtidos pelo método de microtitulação. Os valores de CE50 obtidos pelo método de microtitulação apresentaram correlação de 0,90 e 0,88 com os valores obtidos pelo método de crescimento micelial, para carbendazim e protioconazol, respectivamente. No monitoramento da sensibilidade as CE50 para C. cassiicola para carbendazim (MBC) variaram de 0,0045 a 14,27 μg mL-1 e 0,69 a 2,66 μg mL-1, respectivamente para os isolados do PR e MT; para piraclostrobina (IQo) variaram de 4,17 a 44,91 μg mL-1 e 0,29 a 20,43 μg mL-1, respectivamente, para os isolados do PR e MT; para o protioconazol (IDM) variaram de 0,0033 a 45,11 μg mL-1 (média 4,84 μg mL-1) e 0,0044 a 17,70 μg mL-1 (média 1,90 μg mL-1) para os isolados do PR e MT, respectivamente. Na análise morfológica dos isolados de Colletotrichum spp., foi avaliada o índice de velocidade de crescimento micelial (IVCM); coloração da colônia, borda e reverso da colônia em meio de cultura BDA; presença de peritécio, acérvulo e massa conidial; tamanho e forma dos esporos classificadas em agudo, arredondado e clavado; e severidade em folhas de soja destacadas. Os 87 isolados de Colletotrichum spp., foram classificados como pertencentes a espécie Glomerella glycines ou a fase anamórfica C. truncatum ou, destes 29 foram patogênicos a soja. Análise de agrupamento de dados separou os isolados em 15 e 16 grupos para o experimento 1 e 2 respectivamente, não sendo possível uma diferenciação dos isolados de Colletotrichum spp., como patogênico ou não patogênico a soja, levando em consideração apenas os atributos qualitativos e quantitativos avaliados. Os isolados patogênicos foram utilizados no teste de monitoramento de sensibilidade. As CE50s para C. truncatum variaram de 1,89 a 2,93 μg mL-1 para carbendazim (MBC); de 0,36 a 5,39 μg mL-1 para piraclostrobina (IQo) e de 0,051 a 4,67 μg mL-1 (média 1,39 μg mL-1) para protioconazol (IDM).The sensitivity monitoring to fungicides provide important information to define disease management strategies and avoid unnecessary fungicide applications. The objectives of this study were: i) evaluate the efficiency of the colorimetric microtiter method to determine the sensitivity of the fungus Corynespora cassiicola and perform sensitivity monitoring of fungus toward demethylation inhibitors (DMI), methyl benzimidazole carbamates (MBC) and the quinone outside inhibitors (QoI) fungicides; ii) Perform morphological characterization and pathogenicity of fungus Colletotrichum spp. species isolated from soybean plants and the sensitivity monitoring of fungi toward fungicides DMI, MBC and QoI. To evaluate the efficiency of the colorimetric microtiter method was compared EC50 values (half-maximal effective concentration) to isolates of C. cassiicola obtained by mycelial inhibition growth method with values obtained by microtiter method. The EC50 obtained by microtiter method presented a correlation of 0.90 and 0.88 (p<0.05) with values obtained by mycelial inhibition growth assay for carbendazim and prothioconazole, respectively. On sensitivity monitoring the EC50s of C. cassiicola for carbendazim (MBC) ranged from 0.0045 to 14.27 μg mL-1and 0.69 to 2.66 μg mL-1 respectively for the isolated collected in PR and MT; for pyraclostrobin (QoI) ranged from 4.17 to 44.91 μg mL-1 and 0.29 to 20.43 μg mL-1, respectively, for isolates of PR and MT; for prothioconazole (DMI) ranged from 0.0033 to 45.11 μg mL-1 (mean 4.84 μg mL-1) and 0.0044 to 17.70 μg mL-1 (median 1.90 μg mL-1) for isolates of PR and MT, respectively. In the morphological analysis of the isolates Colletotrichum spp., the mycelial growth rate index (IVCM) was evaluated; colors, border and reverse colony staining in PDA culture medium; presence of perithecium, acervulum and conidial mass; size and shape of the spores classified as acute, rounded and curved; and severity in leaves highlighted. The 87 isolates of Colletotrichum were classified as belonging to Glomerella glycines species or the anamorphic C. truncatum, these 29 were pathogenic to soybean. Data cluster analysis separates the isolates in 15 and 16 groups for experiment 1 and 2 respectively, and it is not possible to differentiate the isolates of Colletotrichum spp. as pathogenic or non pathogenic to soybean, taking into account their own qualitative and quantitative attributes. Only pathogenic isolates were used in the sensitivity monitoring test. The CE50s for C. truncatum ranged from 1.89 to 12.93 μg mL-1 for carbendazim (MBC); 0.36 to 5.39 μg mL-1 for pyraclostrobin (IQo) and 0.051 to 4.67 μg mL-1 (mean 1.39 μg mL-1) for prothioconazole (MDI).
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Vandresen, Camila Chevonica. "Avaliação da atividade fotoinativadora de meso-tetra-arilporfirinas catiônicas em conídios do fungo colletotrichum graminicola." reponame:Repositório Institucional da UFPR, 2013. http://hdl.handle.net/1884/48452.
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Orientadora : Profª. Drª. Sandra Mara Woranovicz BarreiraCoorientador : Prof. Dr. Alan Guilherme Gonçalves
Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Saúde, Programa de Pós-Graduação em Ciências Farmacêuticas. Defesa: Curitiba, 22/02/2013
Inclui referências : f. 108-115
Área de concentração: Insumos, medicamentos e correlatos
Resumo: A inativação fotodinâmica (PDI) consiste em um tipo de intervenção baseado na associação de luz, fotossensibilizador e oxigênio molecular (O2), que resulta na destruição de um alvo biológico específico. Dentre os fotossensibilizadores empregados na PDI, 5,10,15,20-tetraquis(N-metilpiridino-4-il)porfirina (Tetra-Py+ ) tem demonstrado ser efetivo na fotoinativação de diversos micro-organismos. Colletotrichum graminicola é um fitopatógeno que causa antracnose foliar e do colmo em milho (Zea mays L.). C. graminicola é altamente resistente em condições ambientais, sendo também resistente a fungicidas comumente empregados na agricultura. Dessa forma, a antracnose tem causado impacto importante nas culturas de milho do Brasil. Além disso, o uso abusivo de fungicidas na cultura do milho representa um problema de saúde pública. Assim, o objetivo do presente trabalho foi avaliação da fotoinativação de C. graminicola utilizando Tetra-Py +, além de quatro derivados porfirínicos com ambos os grupos N-metil-piridina catiônica meso-ligados e grupos fenil meso-ligados (Tri-Py+, Di -cis-Py+, Di-trans-Py+ e Mono-Py+). Com esse propósito, os experimentos foram realizados empregando suspensões de conídios padronizadas a 105 e 104 conídios / mL. As concentrações dos fotossensibilizadores foram 5, 10, 15 e 25 M e o tempo de irradiação máximo foi ajustado para 20 minutos. Além dos ensaios de fotoinativação, três tipos de experimentos controles foram executados simultaneamente: controle claro, branco e controle escuro. A fotoestabilidade das porfirinas e a produção de oxigênio singlete foram determinadas para todos os compostos. Entre as porfirinas avaliadas, apenas o derivado Di-cis-Py+ demonstrou toxicidade no escuro e, assim, não foi utilizado para estudos de PDI. As outras porfirinas evidenciaram propriedades fotoinativadoras em diferentes níveis, que foram relacionadas com o número de cargas e sua distribuição na estrutura da molécula. Estas características estruturais também refletiram na fotoestabilidade e produção de oxigênio singlete. As porfirinas Tri-Py+ e Di-trans-Py+ demonstraram os melhores resultados, ocorrendo fotoinativação completa na concentração de 5 M, com um tempo de irradiação de cinco minutos. A porfirina Tetra-Py+ mostrou uma propriedade fotoinativadora mais branda, para a qual a fotoinativação total foi evidente na concentração de 50 M, para o mesmo período de cinco minutos irradiação. Por sua vez, a porfirina Mono- Py+ foi o derivado menos eficaz (25 M, 20 minutos), inativando totalmente apenas a suspensão de conídios menos concentrada. Como conclusão, a fotoinativação de C. graminicola empregando meso-tetra-arilporfirinas catiônicas como fotossensibilizadores ocorreu em níveis significativos, demonstrando a possibilidade de utilização desses compostos em associação com a luz solar para inativação do micro-organismo. Esse processo pode contribuir para o controle da antracnose na cultura do milho no Brasil. Palavras-chave: Porfirinas. Síntese química. Inativação fotodinâmica. Colletotrichum.
Abstract: Photodynamic inactivation (PDI) is a type of intervention based on the association of light, photosensitizer and molecular oxygen (O2), which results in the destruction of a specific biological target. Among the photosensitizers utilized in PDI, 5,10,15,20- tetrakis(N-methyl pyridinium-4-yl)porphyrin (Tetra-Py+ ) has demonstrated to be effective in the photoinactivation of diverse microorganisms. Colletotrichum graminicola is a fungal pathogen that causes leaf and stalk anthracnose in maize (Zea mays). C. graminicola is highly resistant under environmental conditions, being also resistant to fungicides commonly used in agriculture. In this way, anthracnose has caused an important impact in Brazil's maize crops. In addition, the abusive use of fungicides in maize cultivation represents a public health issue. Thus, the objective of the present work was the evaluation of C. graminicola photoinactivation using Tetra-Py+, plus four porphyrin-derivatives having both meso-linked N-methyl-pyridine cationic centers and meso-linked phenyl groups (Tri-Py+, Di-trans-Py+, Di-cis-Py+ and Mono-Py+). For this purpose, experiments were performed with standardized conidial suspensions at 105 and 104 conidia/mL. The concentrations of the photosensitizers were 5, 10, 15 and 25 ?M and the maximum irradiation time was set to 20 minutes. In addition to the photoinactivation assays, three types of control experiments were simultaneously executed: blank, light control and dark control. Porphyrin photo-stability and production of oxygen singlet were also determined for all compounds. Among the porphyrins herein evaluated, only Di-cis- Py+ derivative demonstrated toxicity in the dark and thereby it was not employed for PDI studies. The other porphyrins presented photoinactivating properties at varying levels that were related to the number of charges and their distribution in the molecule structure. These structural features also reflected in the photo-stability and singlet oxygen production. Porphyrins Tri-Py+ and Di-trans-Py+ demonstrated the best results, giving complete photoinactivation at 5 ?M with an irradiation time of five minutes. Porphyrin Tetra-Py+ showed a milder photoinactivation property, which was complete at 50 ?M with the same irradiation time. Porphyrin Mono-Py+ was the least effective derivative (25 ?M, twenty minutes), resulting in total inactivation only for the less concentrated conidial suspension. In conclusion, the photoinactivation of C.. graminicola using cationic meso-substituted porphyrins occurred in significant levels, demonstrated the possibility of using these compounds in combination with sunlight for inactivation of microorganism. This process may contribute to the control of maize anthracnose qin Brazil. Key-words: Porphyrins. Chemical synthesis. Photodynamic inactivation. Colletotrichum
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Hughes, Kelvin J. D. "Molecular methods for the diagnosis of fungal quarantine plant pathogens." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272031.
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Abdalla, Mohamed Yasser. "Isolation and characterization of species and races of Colletotrichum occurring in alfalfa /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu148726555543936.
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Venard, Claire Marie-Pierre. "THE DEVELOPMENT OF COLLETOTRICHUM GRAMINICOLA INSIDE MAIZE STALK TISSUES." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_diss/439.
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Colleotrichum graminicola is the causal agent of anthracnose stalk rot, and is one of the most common and aggressive pathogens of maize. The goal of my Ph.D. project was to contribute to a better understanding of the biology of the interaction between C. graminicola and its host. C. graminicola produces two type of asexual spores: one is produced on the surface of infected tissues and is thought to be involved in the spread of the disease in the field. The second type of spore, oval in shape, is produced inside the infected plant tissues, and was believed to be involved in the movement of the pathogen inside the plant tissues via the vascular system. I tested this hypothesis with both cytological and molecular approaches. I used strains of C. graminicola expressing green fluorescent proteins (GFP) to inoculate wounded plants, and followed the development of the pathogen over time. This study revealed that C. graminicola is not a vascular pathogen. C. graminicola primarily moved through the rind and vascular fibers. Oval spores were produced in colonized parenchyma cells and remained dormant, and did not appear to be involved in the movement of the pathogen, at least during the early stages of the disease development. I also studied pathogen ingress in the absence of a wound. I inoculated unwounded plants with the GFP expressing strains. C. graminicola efficiently colonized the epidermis and, given enough time, penetrated and colonized the deeper parenchyma tissues, after first moving through the fibers. To further test the role of sporulation in colonization of maize tissues, I used targeted mutagenesis to disrupt a major gene known to regulate sporulation and vegetative growth in several other fungi. The gene Cgg1, orthologue of the A. nidulans fadA, was disrupted using the split marker method. The Cgg1 mutants were less pathogenic than the wildtype to wounded plants. This was associated with an apparent increase in production of spores and primary infection hyphae. This suggests that Cgg1 signaling pathway plays a role in maximizing colonization of host tissues, and that this involves negative regulation of sporulation and primary hyphae production in planta.
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Parada, André Luís Duarte. "Caracterização da resistência a Colletotrichum kahawae em Coffea spp." Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/4051.
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Mestrado em Engenharia Agronómica - Instituto Superior de AgronomiaCoffee is one of the most valuable agricultural products in world trade being crucial to the economies of many developing countries. However its production is constrained by a number of major diseases, including Coffee Berry Disease (CBD) caused by Colletotrichum kahawae Waller & Bridge. Currently CBD is limited to Africa, constituting a serious threat to other coffee growing countries in other continents. This disease is responsible for up to 80% of crop losses, if no control measures are applied. The most widely used method to control this disease involves the application of fungicides. However some institutions in some coffee growing countries are developing breeding programs for the creation of resistant varieties to this pathogen. In this work resistance of different tetraploid interspecific coffee hybrids were characterized by pre-screening tests and several genotypes with different levels of resistance to some C. kahawae isolates were selected. Additional observations were made in hypocotyls inoculated with different isolates of C. kahawae allowed the characterization of dilatory resistance in coffee genotypes classified as susceptible. Histological studies were also made in hypocotyls with the aim of evaluating their behaviour compared with other known genotypes.
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Takano, Yoshitaka. "Molecular Genetic Studies on Appressorial Melanization of Colletotrichum lagenarium." Kyoto University, 1998. http://hdl.handle.net/2433/78087.
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MACIEL, Danielli Barreto. "Gene de patogenicidade cap20 em isolados de Colletotrichum gloeosporioides." Universidade Federal de Pernambuco, 2008. https://repositorio.ufpe.br/handle/123456789/418.
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Previous issue date: 2008Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O primeiro evento para a penetração em algumas espécies de Colletotrichum, inicia com a adesão do conídio e germinação na superfície da planta hospedeira, produzindo tubo germinativo e então formando o apressório, que penetra diretamente na cutícula. Estudos anteriores têm identificado em Colletotrichum gloeosporioides, genes denominados cap, que são unicamente expressos durante a formação do apressório depois de 4 horas de exposição do conídio à presença da cera da cutícula do abacate (Persea gratissima). O objetivo deste trabalho foi amplificar o gene da patogenicidade cap20 e analisar a variação deste gene intraespecificamente em isolados de C. gloeosporioides provenientes de diferentes hospedeiros. A variabilidade genética foi acessada usando marcadores de RFLPITS e intron (primer EI1) e pelo método de agrupamento UPGMA. Primers para o gene cap20 foram construídos a partir de seqüências selecionadas do GenBank (National Center of Biotechnology Information, http://www.ncbi.nlm.nih.gov) utilizando o programa Primer 3. A análise dos dendrogramas revelou que o marcador RFLP-ITS foi capaz de separar as espécies C. gloeosporioides, C. acutatum e C. sublineolum. Em outra mão, esses resultados também mostraram que o primer EI1 de Intron Splice Site evidenciou maior variabilidade genética que o RFLP-ITS, porém não separou as espécies. Os primers construídos nomeados P1 e P2 para o gene cap20 foram eficientes para amplificar C. gloeosporioides (exceto para cinco isolados de manga e um isolado de pimentão), C. boninense, C. dematium, C. capsici e C.gossypii var. cephalosporioides, mas não houve amplificação para C. graminicola, C. acutatum, C. sublineolum e C. coccodes, indicando que este gene pode apresentar diferenças na estrutura entre os isolados de C. gloeosporioides relacionada ao hospedeiro e que este gene também está presente nas outras espécies citadas de Colletotrichum. A digestão com a enzima MspI para os isolados de C. gloeosporioides que apresentaram amplificação não evidenciou diferenças na estrutura do gene cap20
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VIEIRA, Willie Anderson dos Santos. "Prevalência de isolados de Colletotrichum spp. endofíticos em mangueira." Universidade Federal Rural de Pernambuco, 2012. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6664.
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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
In the current study the Colletotrichum species isolated from mango in Pernambuco state in Brazil are described, as well as their distribution in different plant tissues. The Colletotrichum isolates are characterized through cultural, morphological, patogenicty and vivirulence data, and from phylogenetic analyses based on a partial sequence of the gene glyceraldehyde-3-phosphate dehydrogenase (GPDH). There was significant difference in isolament frequency among sites and plant tissues. In the locality of Aldeia (site III) it was observed the highest isolation frequency. The old limb was the part of plant most colonized in a higher number of sites. Colletotrichum asianum, C. fructicola, C. cliviae, C. boninense and two unidentified species were found as endophyte in mango, and C. asianum was prevalent over the other. All isolates were pathogenic in mango fruits. The phylogenetic analysis revealed groupings that were congruent with morphological characters, but did not group isolates according to phenotypic characters. There was no distribution pattern of species in different areas, neither in plant tissues.
No presente estudo são relatadas as espécies de isolados de Colletotrichum endofíticos associados a mangueiras no Estado de Pernambuco/Brasil, e sua distribuição nos diferentes tecidos da planta em cinco diferentes áreas. Isolados foram caracterizados cultural e morfologicamente, quanto à patogenicidade e virulência, e através de inferências filogenéticas baseadas na sequência parcial do gene gliceraldeído-3-fosfato desidrogenase (GPDH). Houve diferença significativa na freqüência de isolamento de Colletotrichum em função da área de coleta e do tecido da planta. Na localidade de Aldeia (área III) foi observada a maior freqüência de isolamento de Colletotrichum. O limbo maduro foi a parte da planta mais colonizada por Colletotrichum em um maior número de áreas. Colletotrichum asianum, C. fructicola, C. cliviae, C. boninense e duas espécies não identificadas ocorrem como endófitas em mangueira, e C. asianum foi prevalente sobre as demais. Todos os isolados foram patogênicos em frutos de manga. A análise filogenética revelou agrupamentos que foram congruentes com os caracteres morfológicos analisados, porém não agrupou isolados conforme características fenotípicas. Também não foi observado padrão de distribuição das espécies nas diferentes áreas, nem nos tecidos vegetais.
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Rezende, Dalilla Carvalho. "Efeito de compostos orgânicos voláteis identificados a partir de Saccharomyces cerevisiae sobre Colletotrichum gloeosporioides e Colletotrichum acutatum e no controle da antracnose em goiaba." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-08022011-164031/.
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A antracnose, que tem como agentes causais os fungos Colletotrichum gloeosporioides e C. acutatum, é uma das principais doenças que afetam a cultura da goiabeira. Não há no Brasil, fungicidas registrados para o controle da doença em pós-colheita. Em vista disso e da preocupação em relação à saúde humana e o respeito ao ambiente vem crescendo pesquisas envolvendo a utilização de agentes alternativos para o controle de doenças. Foi verificado em trabalho prévio que a levedura S. cerevisiae, apresentou atividade antagônica in vitro contra vários fitopatógenos, dentre eles C. gloeosporioides. Essa inibição foi atribuída à produção de uma mistura de compostos orgânicos voláteis (COVs), sendo que os álcoois 3-metil-1-butanol (3M1B) e 2-metil-1-butanol (2M1B) foram apontados como os principais responsáveis por essa atividade. Considerando a importância do manejo pós-colheita e o potencial da utilização de COVs no controle da antracnose, os objetivos desse trabalho foram avaliar o efeito in vitro dos COVs 3M1B e 2M1B identificados a partir de S. cerevisiae no desenvolvimento de Colletotrichum sp, elucidar alguns dos possíveis mecanismos de ação atuantes no processo inibitório e avaliar a utilização dos COVs no controle pós-colheita da antracnose em frutos de goiaba. Foi observado aumento da inibição do crescimento micelial dos fitopatógenos à medida que houve aumento da concentração dos compostos, chegando a 100% a partir da dose de 1µL mL-1 de ar. Os menores valores de MIC50 para C. gloeosporioides e C. acutatum, foram 0,34 e 0,31 quando tratados com os compostos 3M1B e a mistura 3M1B:2M1B (10:1; v/v), respectivamente. Ambos os fitopatógenos retomaram o crescimento quando transferidos para novo meio na ausência dos COVs, caracterizando a natureza fungistática da inibição. A esporulação de C. acutatum também foi totalmente inibida nas doses testadas. Também foram observados efeitos negativos sobre a produção de biomassa fúngica por C. gloeosporioides e C. acutatum, em média 64,9% e 55,4% menores, respectivamente, após a exposição aos COVs. Com relação aos possíveis mecanismos de ação atuantes no processo inibitório, os ensaios indicam que os voláteis podem causar aumento na permeabilidade da membrana plasmática, tendo como consequência a perda de eletrólitos. Foram verificados maiores níveis de peroxidação dos lipídios de membrana quando expostos aos voláteis, indicando um possível processo de estresse oxidativo. Não foram verificadas alterações significativas no conteúdo de proteínas do micélio dos fitopatógenos. O potencial de utilização do 3M1B no controle da antracnose em pós-colheita foi avaliado em frutos inoculados com C. acutatum e posteriormente tratados com o volátil por 10h. A incidência e a severidade da doença nos frutos tratados alcançaram valores 5 e 6,25 vezes maiores, respectivamente, quando comparado com o controle no último dia de avaliação. Também foi avaliado o efeito do tratamento sobre qualidades físico-químicas dos frutos, e não foram observadas alterações em nenhum dos parâmetros avaliados. Os COVs utilizados nesse estudo são capazes de interferir no desenvolvimento de C. gloeosporioides e C. acutatum, porém nas condições experimentais do trabalho, mostraram-se inadequados para o controle da antracnose em goiaba.The anthracnose, which has as causal agents the fungi Colletotrichum gloeosporioides and C. acutatum, is one of the main diseases that affect guava plants. In Brazil, there are not fungicides registered for the control of the disease in post-harvest conditions. This aspect and the concern about human health and the environment, made increase researches involving the use of alternative agents to control diseases. In a previous study, it was shown that the yeast S. cerevisiae exhibited antagonistic activity in vitro against several pathogens, including C. gloeosporioides. This inhibition was attributed to the production of a mixture of volatile organic compounds (VOCs), and the alcohols 3-methyl-1-butanol (3M1B) and 2-methyl-1-butanol (2M1B) were identified as the main ones, responsible for the activity. Considering the importance of post-harvest management and the potential use of VOCs in the anthracnose control, the objectives of this study were the evaluation of the in vitro effect of 3M1B and 2M1B VOCs identified from S. cerevisiae on the development of Colletotrichum, the elucidation of some of the possible mechanisms acting during the inhibitory process and the evaluation of the use of VOCs in postharvest anthracnose control of guava fruits. An increased inhibition was observed in mycelial growth of the pathogens as the concentration of the compounds increased, reaching 100% of inhibition in the dose 1L mL-1 of air. The lowest values of MIC50 for C. gloeosporioides and C. acutatum were 0.34 and 0.31, respectively when treated with the compound 3M1B and the mixture 3M1B:2M1B (10:1; v/v). Both pathogens regained growth when transferred to a new medium in the absence of VOCs, thus characterizing the fungistatic nature of the inhibition. The sporulation of C. acutatum was also completely inhibited at all tested doses. There were negative effects on the production of fungal biomass by C. gloeosporioides and C. acutatum, being 64.9% and 55.4% lower on average, respectively, after exposure to VOCs. Regarding the possible mechanisms actinng in the inhibitory process, the results indicated that the volatiles could increase the permeability of the plasma membrane, resulting in the loss of electrolytes. It was observed higher levels of peroxidation of membrane lipids when exposed to volatiles, suggesting a oxidative stress process. There were not significant alterations in protein content of the pathogen mycelium. The potential use of 3M1B in postharvest anthracnose control was evaluated in fruits inoculated with C. acutatum and subsequently treated for 10h with the volatile. The incidence and severity of disease in the treated fruits showed values 5 and 6.25 higher, respectively, when compared to the control treatment on the last day of evaluation. The effect of treatment was evaluated on the physico-chemical quality of the fruits, and no changes were observed in any of the parameters. The VOCs used in this study are able to interfere on the development of C. gloeosporioides and C. acutatum, but, under the experimental conditions of the work, the VOCs were not adequate to control the anthracnose of guava.
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Medeiros, Luis Aquiles Martins. "Resistência genética do feijão (phaseolus vulgaris l.) ao Colletotrichum lindemuthianum." Universidade Federal de Santa Maria, 2004. http://repositorio.ufsm.br/handle/1/3158.
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One hundred and twenty eight genotypes of common bean
(Phaseolus vulgaris L.) divided into local varieties, cultivars and lines both from meso-america and andean gene pool, were evaluated in 2003 and 2004. Several experiments were conducted at Universidade Federal de Santa Maria, State of Rio Grande do Sul, Brazil. Host genetic structure was studied based on reaction on juvenile resistance (V1/V2) to 12 physiological races of Colletotrichum lindemuthianum. Also, the relation among three phonological stages (V1/V2; R4/R5 and R5/R6) of 26 germplasm and the reaction to four races of Colletotrichum lindemuthianum was characterized. The plant reaction, virulence and resistance index were obtained from a 1 to 9 scale. The phenetic analysis was generated from virulence data considering incompatible reaction (0) and compatible reaction (1). Common bean germplasm variability was not coherent to decade of release, origin and gene pool. Higher diversity was observed among local genotypes than commercial ones. Variability of common bean lines was not related to population structure of the pathogen. The absence of Mexican genes (Co-4 and Co-5) was observed in genotypes with resistance index higher that 80%. Higher frequency of resistant genotypes was observed from 1980 to 1990. However, such result was not applied to the wide spread virulence genes. Phenetic data analysis showed that intrinsic diversity was observed among local genotypes of common bean. Specific interactions between genotypes and races were observed as growth stage evolved.Nos anos de 2003 e 2004, na Universidade Federal de Santa Maria, foram avaliados cento e vinte e oito genótipos de feijoeiro comum (Phaseolus vulgaris L.) locais, cultivares comerciais e linhagens de origem meso-americana e andina, com o objetivo de caracterizar sua estrutura genética quanto à resistência a 12 raças fisiológicas de Colletotrichum lindemuthianum, no estádio juvenil (V1/V2). Destes genótipos, vinte e seis foram selecionados e inoculados em 3 estádios fenológicos (V1/V2; R4/R5 e R5/R6), com 4 raças fisiológicas de C. lindemuthianum, sendo avaliada a proporção de reações resistentes de acordo com a idade da planta. Reações caracterizadas com base em uma escala de notas de severidade de 1 a 9, permitiram calcular os índices de resistência dos genótipos e da virulência das raças. A análise fenética dos dados de virulência foi obtida a partir da construção de uma matriz, considerando as reações incompatíveis (0) e as reações compatíveis (1). A variabilidade em germoplasma de feijão não se mostrou coerente com a década de lançamento, local origem e pool gênico. Não foi observado aumento significativo na proporção de genótipos resistentes entre as décadas de 80 e 90, assim como não houve incremento de alguns genes de virulência especialmente dispersos e abundantes. Genótipos que apresentaram índice de resistência superior a 80% não continham genes Mexicanos (Co-4 e Co-5). Variabilidade em linhagens não se mostrou ligada à estrutura populacional de C. lindemuthianum. A análise fenética mostrou que maior diversidade intrínseca foi observada entre os genótipos locais de feijoeiro comum. Para interações específicas entre genótipos e raças, foi observada variação na resistência relacionada com o envelhecimento da planta.
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Danaher, J. E. "The prediction and manipulation of Colletotrichum coccodes on Solanum tuberosum." Thesis, University of Aberdeen, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590960.
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As all underground parts of a potato plant can be infected with Colletotrichum coccodes it was speculated that it may be possible to predict black dot development on harvested tubers by assessing stems and stolons for the presence of the disease in the growing crop. In a 3-year study stems and stolons were assessed for black dot in 123 potato crops and its incidence related to disease on the tubers at harvest. In cvs Estima and Maris Piper, if stems or stolons showed black dot symptoms as the onset of crop senescence then the disease was likely to be present on tubers at harvest. No relationship between black dot on stems and stolons in the growing crop and disease on tubers at harvest was found in the cv. Saxon. To explain these results a series of glasshouse and field experiments were performed to identify when symptoms of black dot developed on underground parts of a potato plant. Results showed that infection by C. coccodes could occur soon after these plant parts had formed. Visual symptoms did not appear on stems and stolons till just prior to foliage senescence and on tubers until after the start of foliage senescence. Further research considered whether a reduction in black dot symptoms on tubers is achievable through haulm destruction methods in the field. Results indicated that in a crop of cv. Maris Piper, where there was a high incidence of black dot, and no one technique gave a significant reduction in symptom developing on tubers. These inconclusive results are discussed.
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Baroncelli, Riccardo. "Colletotrichum acutatum sensu lato : from diversity study to genome analysis." Thesis, University of Warwick, 2012. http://wrap.warwick.ac.uk/56428/.
Full textAbstract:
Colletotrichum acutatum sensu lato includes a number of important pathogens that cause economically significant losses of various crops. The C. acutatum species complex has a wide host range in both domesticated and wild plant species, and its capability to infect different types of hosts such as insects has also been described. Members belonging to this complex are able to develop three different types of interaction with plant hosts including biotrophic, necrotrophic and hemibiotrophic infections and are also capable of surviving on weeds and non-hosts without causing visible symptoms. They are mainly asexual, but some have a teleomorphic state called Glomerella and can be either homothallic or heterothallic. The sexual behaviour in Glomerella is more complicated than in most ascomycetes, and strains within the same species do not show a typical MAT1-1/2 system. The overall aim of this study was to gain an improved understanding of the relationships between the genetic diversity of global populations, host association patterns, geographic distribution and biological and pathological attributes. A database (CaITSdb) containing more than 800 rRNA sequences deposited in GenBank was created along with key biogeographic information, and the data have been analysed in order to investigate genetic diversity and distribution of sub-populations and their evolutionary relationships. The combined evidence was used to assemble a core collection of 120 isolates that are representative of the diversity in host preference, geographic origin, mating behaviour and molecular genetic variation. A multi-locus sequencing approach (based on four neutral loci) has been used to evaluate phylogenetic relationships amongst the isolates in the core collection. A strong relationship was observed between various genetic groups distinguished and their mating behaviour, geographic distribution and host association patterns. Oceania has been identified as a likely geographic origin of this pathogen, as the highest level of variability and groups related to a hypothetical ancestral population are mainly distributed in these countries. All homothallic isolates capable of producing perithecia belonged to the same genetic group A7; whereas all self-sterile heterothallic isolates were classified as either A3 or A5. Isolates derived from the same host tend to cluster together into genetic groups or sub-populations. This evidence is generally in agreement with recent published work on taxonomic re-assessment of Colletotrichum acutatum sensu lato, which indicates at least fifteen new species. This study has provided the evidence for the occurrence of three distinct genetic groups on strawberry in the UK corresponding to three species reported in the literature namely, C. nymphaeae, C. fioriniae and C. godetiae. Isolates belonging to the genetic groups that correspond to C. nymphaeae and C. fioriniae appeared to be the most aggressive on strawberry, followed by C. godetiae, and C. simmondsii (not found in the UK). Representative isolates of other species were less aggressive. The first whole genome sequence an isolate (A9 = C. simmondsii) from the C. acutatum sensu species complex was assembled and analysed using a range of bioinformatics algorithms. An isolate of C. simmondsii was chosen based on its wide host range including strawberry and the phylogeographic position. Genome analyses enabled prediction and annotation of the whole gene set at 13549 including 6 % unique to this species. The data also suggested an interesting expansion of several gene families, such as those encoding carbohydrate-active enzymes, secondary metabolites pathways and effectors which could be associated with the wide host range. The new knowledge and resources developed with the genome analyses along with the results of the population level diversity studies provide a platform for future comparative and functional genomics investigations to advance this research.
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Bragança, Carlos Augusto Dórea. "Molecular characterization of Colletotrichum spp. associated with fruits in Brazil." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-23042013-154938/.
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Colletotrichum species are considered one of the most economically important plant pathogens. They cause many losses in tropical, subtropical and temperate regions affecting a wide range of plant species. In tropical and subtropical regions C. gloeosporioides and C. acutatum are associated with significant losses on pre and post-harvest anthracnoses. There are still many features to understand about Colletotrichum biology and its systematics. The accurate identification of species involved with each anthracnose is of high relevance to establish management strategies to control the disease. Although the great advances on Colletotrichum systematics, species complex such as C. gloeosporioides and C. acutatum are used in a broad sense in Brazil. These complexes were recently investigated and showed to be highly genetic and geographic variable. In this study multigene analysis were carried out based on ITS, GAPDH, CHS-1, TUB2 and CAL or HIS3 partial sequences for strains of C. gloesporioides and C. acutatum complexes collected from fruit crops in Brazil. Strains from different countries and exepitypes and others sequences available on GenBank from the species accepted on both complexes were added on dataset. Six strains from C. gloeosporiodes complex and five for C. acutatum were selected based on multigene phylogeny to investigate the pathogenicity through inoculations on detached fruit. The multigene phylogenies showed the occurrence of species in Brazil related to those complexes with a high genetic variability among them. The phylogeny of Brazilian strains belonging to the C. gloeosporioides complex showed that C. siamense represents the most genetically and host-specific variable clade. In contrast, C. asianum clade grouped only strains isolated from mango. The strains from this clade used on pathogenic test were not able to infect avocado and one of the strains caused symptoms only on mango. All strains from Brazil grouped in one subclade within the C. fructicola clade and seem to represent a genetically distinct group. C. theobromicola is first reported causing anthracnose on acerola fruit. Three new species (C. polyphialidicum, C. paranaense and C. pruni) belonging to the C. acutatum complex were recognized and their morphologic descriptions were provided. The pathogenic test for the strains in the C. acutatum complex showed their cross infection ability, but in some cases the larger lesions were produced on the original host. Most brazilian strains from C. acutatum complex grouped in one subclade within the C. nymphaeae clade and seem to be genetically distinct.Fungos do gênero Colletotrichum são considerados um dos mais importantes economicamente na Fitopatologia. Espécies desse gênero são encontradas amplamente disseminadas e estão associadas a diversas espécies de plantas hospedeiras. Em regiões tropicais e subtropicais, espécies dos complexos C. gloeosporioides e C. acutatum são a principal causa das antracnoses em pré e póscolheita de frutos e consequentemente causam significantivas perdas. Ainda há muitos aspectos a serem compreendidos sobre o gênero Colletotrichum, como a biologia e a sistemática. A acurada identificação das espécies associadas a antracnoses é de suma importância para o estabelecimento de estratégias de controle. No entanto, apesar dos grandes avanços na sistemática desse gênero, complexos de espécies como aquelas citadas acima são tratados de modo genérico no Brasil. Estes complexos de espécies foram recentemente estudados e considerados geneticamente e geograficamente variáveis. Neste sentido, o presente trabalho teve como objetivo caracterizar isolados de Colletotrichum spp. associados a diferentes frutos e regiões do Brasil por meio de análise filogenética. Para análise multilocus, foram utilizadas sequências parciais dos genes ITS, GAPDH, CHS-1, TUB2 and CAL ou HIS3. Sequências de espécies-tipos disponíveis no GenBank e de isolados de diferentes países foram adicionadas ao conjunto de dados. Com base nos resultados obtidos por meio de filogenia multilocus, seis isolados do complexo C. gloeosporiodes e cinco do complexo C. acutatum foram escolhidos para testes de patogenicidade cruzada. A espécie C. siamense, pertencente ao complexo C. gloeosporioides, foi a mais variável geneticamente e quanto ao hospedeiro de origem. Diferentemente, apenas isolados obtidos de manga se agruparam no clado C. asianum. Isolados agrupados neste clado não infectaram abacate e um dos isolados (CPC 20969) causou sintomas apenas em manga. No clado C. fructicola, isolados coletados no Brasil se agruparam em um subclado e parecem representar um grupo geneticamente distinto. A espécie C. theobromicola é relatada pela primeira vez em acerola. Foram identificadas três novas espécies, C. polyphialidicum, C. paranaense e C. pruni, pertencentes ao complexo C. acutatum. Isolados brasileiros agrupados no clado C. nymphaeae parecem representar um grupo geneticamente distinto, todos se agruparam em um subclado. Isolados do complexo C. acutatum utilizados no teste de patogenicidade provocaram sintomas nos hospedeiros testados, porém, em algumas inoculações, as lesões foram maiores no hospedeiro de origem.
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Nascimento, Jefferson Fernandes. "Resistência do algodoeiro e variabilidade de Colletotrichum gossypii var. cephalosporioides." Universidade Federal de Viçosa, 2000. http://www.locus.ufv.br/handle/123456789/10101.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O índice de doença para as quatro cultivares e 21 linhagens avaliadas variou de 20,0 a 57,1 e a AACPD de 567 a 1627. Ficaram evidenciados dois grupos distintos, um formado por duas cultivares e nove linhagens suscetíveis e o outro por duas cultivares e 12 linhagens resistentes. De modo geral, o ID apresentou crescimento linear para as 25 cultivares e, ou linhagens avaliadas. A linhagem CNPA 94-101 empregada como padrão de suscetibilidade apresentou valores médios de INC=83,4, ID=57,1 e AACPD=1.627,7 sendo, portanto a mais suscetível. Por outro lado, a linhagem CNPA 96-08 apresentou INC=37,8, ID=20,0 e AACPD=567,7 sendo a mais suscetível. Dentre as cultivares comerciais a IAC 22 foi a mais suscetível, com ID=47,3 e a CNPA Precoce2, utilizada como padrão de resistência foi a mais resistente, com ID=28,9. Foi observado que os dez isolados utilizados apresentaram grande virulência, que variou em função do genótipo no qual foram inoculados. O isolado MTRM 14, oriundo do Estado do Mato Grosso, foi o menos virulento e o isolado RAV 20, de Minas Gerais, o mais virulento, com ID= 6,36 e ID=46,47, respectivamente. A Linhagem HR 102 e a cultivar ANTARES foram as mais resistentes com ID=18,32 e 19,14, respectivamente. Portanto, ocorreu variabilidade entre os dez isolados estudados quanto à virulência e variação na resistência das cultivares e linhagens de algodão aos isolados. Efetuou-se análise de agrupamento e observou-se a separação de dois grupos distintos de isolados, um mais virulento e outro menos virulento.
The index of the disease (ID) in four cotton cultivars and twenty one line varied from 20 to 57,1; and the AADPC from 567 to 1627. Two distinct group of plants was formed; one group (susceptible) had two cultivars and nine lines, and another (resistant groups) had two cultivars and 12 lines. The ID was linear for all the 25 cultivars and cotton lines evaluated. The line CNPA 94-101, used as a susceptible pattern, had ID=57,1, AADPC=1.627,7 and 83,4 of incidence. But in the trial the most susceptible line was CNPA 96-08 with ID=20,0, AADPC=567,7 and incidence equal to 37,8. Among the comercial cultivars the IAC-22 was the most susceptible, with ID=47,3 whereas CNPA Precoce 2 used as a pattern of resistance was the most resistant line (ID=28,9). The ten isolates of the pathogen used were highly virulent, and varied according to the cotton genotype. The isolate MTRM 14 from Mato Grosso State was the least virulent, and the isolate RAV 20 from Minas Gerais State the most virulent with ID=6,36 and 46,47, respectively. The line HR 102 and the cultivar ANTARES were the most resistant with ID=18,32 and 19,14, respectively. In conclusion it was observed great variability on the population of C. gossypii var. cephalosporioides and great variation on the plant genotype. Two distinct groups of isolate of the pathogen was found, one virulent and another less virulent.
Dissertação importada do Alexandria
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Paresqui, Leonardo. "Patogenicidade de Colletotrichum gloeosporioides Penz. ao Cafeeiro (Coffea arabica L.)." Universidade Federal de Viçosa, 2003. http://www.locus.ufv.br/handle/123456789/10130.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Neste trabalho foram conduzidos experimentos em laboratório, visando estabelecer a patogenicidade de Colletotrichum sp. ao cafeeiro (Coffea arabica L.). Isolamentos de Colletotrichum sp. foram feitos a partir de material coletado em quatro estados: Minas Gerais, São Paulo, Espírito Santo e Paraná. A partir dos isolamentos foram obtidas 180 culturas monospóricas, mantidas em sílica-gel, visando à preservação. Entre as 180 culturas inoculadas, em ramos com três rosetas de frutos verdes, houve diferença na incidência observada, tanto nos ramos com ferimento como naqueles sem ferimento, dez dias após a inoculação. A incidência máxima obtida foi de 69,5%, entretanto a testemunha, atomizada com água estéril, também manifestou sintomas e abundante esporulação de Colletotrichum gloeosporioides, resultado novamente observado quando da repetição do experimento. Isso gerou dúvidas sobre a eficiência da sanitização dos ramos e frutos verdes coletados no campo. As amostras passaram por um processo de esterilização superficial, utilizado nas etapas para isolamento de organismos endofíticos. Pôde-se observar que, mesmo superficialmente estéreis, os tecidos apresentavam abundante esporulação de C. gloeosporioides após seis dias de incubação em condições assépticas. Testes de patogenicidade foram então realizados, com e sem ferimento, utilizando-se três isolados, os quais foram inoculados em plantas oriundas de cultura de tecido, com três meses de idade, não sendo observados sintomas por mais de 20 dias após a inoculação. Porém, conseguiu-se recuperar o fungo das plantas inoculadas, mesmo depois de lavadas em água corrente, álcool 70% e cloro ativo 2%. Isso mostra que o organismo penetrou nos tecidos, entretanto sem manifestar sintomas. A partir desses resultados, concluiu-se que testes de patogenicidade de C. gloeosporioides devem ser conduzidos em plantas de cultura de tecido, a fim de se assegurar a sanidade do material a ser inoculado, visto que, mesmo após esterilização superficial do tecido, o organismo pode permanecer latente. Neste trabalho, obtiveram- se indícios de que C. gloeosporioides apresenta relação endofítica nos tecidos de cafeeiro (Coffea arabica).
This work had the objective to establish the pathogenicity of Colletotrichum sp to Coffea arabica. Isolations of Colletotrichum sp. were done from material collected in the field in four States: Minas Gerais, São Paulo, Espírito Santo and Paraná. It was obtained 180 monoconidial cultures and maintained in silica-gel, for preservation. Among the 180 inoculated cultures, in branches with 3 rosettes of green fruits, there was difference in the incidence in the wounded and not wounded branches 10 days after the inoculation. The maximum incidence was of 69.5%, however check treatment atomized with sterile water, also manifested symptoms and abundant sporulation of C. gloeosporioides, the same results was observed again when the experiment was repeated. This generated doubts on the efficiency of the sanitization of the branches and green fruits collected in the field. The tissue samples went by a superficial sterilized process, used in the stages to isolate endofitic organisms. It was observed that even superficially sterile, the tissues presented abundant sporulation of C. gloeosporioides after six days of incubation in aseptic conditions. Pathogenicity tests were then accomplished, with and without wound, using three isolates in three months old coffee seedlings of tissue culture. No symptoms observed for more than 20 days after the inoculation. However, the fungus was recovered of the inoculated plants, even after they had been washed in running water, alcohol 70% and active chlorine 2%. However, C. gloeosporioides was isolate from the inoculated tissue, although no symptoms were observed. From these results it was concluded that pathogenicity tests C. gloeosporioides, should be performed in plants from tissue culture, because, even after superficial sterilization of the tissue, the organism can be in the stage latent. In this work it was obtained, indications that C. gloeosporioides presents endofitic relationship in the tissues of Coffea arabica.
Dissertação importada do Alexandria
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Moreira, Antônio José Araújo. "Epidemiologia da antracnose foliar da cebola, causada por Colletotrichum gloeosporioides." Universidade Federal de Viçosa, 2000. http://www.locus.ufv.br/handle/123456789/11004.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Guidoval e Guiricema são municípios tradicionais produtores de cebola na Zona da Mata de Minas Gerais. Nesses municípios, durante um ano de inspeções de plantios de cebola, verificou-se que os principais problemas fitossanitários foram o ataque de Thrips spp. e a ocorrência das doenças: mancha púrpura e antracnose foliar, causadas por Alternaria porri (Ellis) Cif. e Colletorichum gloeosporioides, respectivamente. Dentre as doenças, a antracnose foliar é a principal e perdas de até 100% da produção foram observadas em lavoura da região. Estudou-se a importância de sementes, restos culturais e hospedeiros alternativos, como fontes de inóculo do patógeno e monitorou-se o progresso da doença. Não se detectou o patógeno em sementes. Verificou-se que o fungo pode sobreviver em restos de folhas doentes, em condições de laboratório e de campo. Em laboratório, o fungo foi detectado por até 137 dias nos restos mantidos em ambiente seco a 15, 20 e 30°C e nos mantidos em câmara úmida a 20°C. Em condições de campo, o patógeno foi detectado por até 118 dias na superfície e a 5 cm de profundidade e por até 33 e 72 dias a 10 e 15 cm de profundidade, respectivamente. Isolados de C. gloeosporioides de diferentes hospedeiros causaram sintomas em folhas de cebolas. Observou-se diferença de virulência de isolados em frutos de mamão, o que sugere haver variabilidade entre eles. Estudou-se o progresso da antracnose foliar em dois ensaios de campo. No primeiro, avaliou-se a incidência da doença em plantas originárias de mudas tratadas ou não com fungicidas no viveiro e, ou no transplantio. O tratamento de mudas no viveiro retardou o início da epidemia e o tratamento no transplantio reduziu os valores de área abaixo da curva de progresso e de incidência máxima de doença. No segundo, avaliou-se a incidência em plantas de quatro cultivares. Em ‘Régia’, obtiveram-se menores valores de incidência inicial de doença, de área abaixo da curva de progresso da doença e da taxa de progresso da doença.
Onion is cultivated tradicionally in Guidoval and Guiricema – MG, where crop losses due to the Twister, caused by Colletotrichum gloeosporioides, can reach 100%. The role of seed, plant debris, and alternative hosts as inoculum sources of the pathogen, and disease progress were studied. The fungus was not detected associated with seeds. It survived in plant debris, under laboratory, and field conditions. In the laboratory, C. gloeosporioides was detected for 137 days in the debris kept at 15, 20, and 30°C, without moist chamber, and at 20°C in moist chamber. In the field, the pathogen survived for 118 days in debris kept on soil surface and at 5 cm depth and for 33 and 72 days at 10 and 15 cm depth, respectively. Isolates of C. gloeosporioides from different hosts caused disease symptoms in onion. The virulence of those isolates was variable in papaya fruits. Disease progress was studied in two field experiments. In the first, disease incidence was assessed in plants originated from fungicide treated. The use of fungicides in the nursery delayed the beginning of the epidemics and the treatment of seedlings for transplanting reduced the values of area under disease progress curve and maximum incidence. Epidemic components were similar for either plants treated or not before transplanting. For the second experiments, disease incidence was assessed in plants of four cultivars. Smaller values of initial disease incidence, area under disease progress curves and disease progress rate were estimated for ‘Régia’.