Academic literature on the topic 'Tuber spp'
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Journal articles on the topic "Tuber spp"
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Islam, Md Tariqul, Rais Uddin Chowdhury, Rozina Afroz, Sajia Rahman, and Md Mamtazul Haque. "Characterization and Maintenance of Yam (Dioscorea Spp.) Germplasm." Bangladesh Journal of Agricultural Research 36, no. 4 (2012): 605–21. http://dx.doi.org/10.3329/bjar.v36i4.11748.
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Three experiments were conducted with 60 germplasm accessions of yam (Dioscorea spp.) at Plant Genetic Resources Centre of BARI for characterization and conservation of germplasm. Fifty-nine germplasm accessions of D. alata L. and one accession of D. bulbifera L. from different districts of Bangladesh were used. Clockwise twining direction was found in D. bulbifera and anti-clockwise twining direction was exhibited in all D. alata germplasm accessions. Potato like aerial tuber was found in D. bulbifera. Round, oval, elongate, flattened to irregular aerial tuber shape were found. Grayed-brown, brown to grayed-orange skin colour with yellow, yellow-orange to grayed-orange of aerial tuber flesh colour were observed among the yam germplasm accessions. Oval-oblong, cylindrical, flattened, corm, rhizome to irregular shape of underground stem or tubers were observed. Low, medium to dense types of spiniess of roots were found on the tubers. Grayed-orange, red to black tuber skin colour along with white, yellowish-white, yellow, yelloworange, red to purple tuber flesh colours were found. Significant variations were also observed in stem shape at base, colour of stem, wing and petiole wing, position of leaf, leaf shape and distance between leaf lobes. Low to high phenotypic diversity was exhibited among the germplasm accessions. The germplasm accessions produced 1 to 30 under ground tubers per plant. The main tuber length ranged from 5.4 to 66.4 cm and breadth from 2.5 to 15.5 cm. The germplasm accessions produced 0.51 kg to 16.45 kg tuber yield per plant. The maximum variability was found in tuber yield per plant (98.74%) and the minimum was found in leaf length (12.55%).The under ground tubers of yam were harvested and replanted at an interval of two to three years from 1995 at PGRC. The plants were grown on bamboo trail in the field genebank. Necessary intercultural operations are done for maintaining the yam germplasm accessions. DOI: http://dx.doi.org/10.3329/bjar.v36i4.11748 Bangladesh J. Agril. Res. 36(4): 605-621, December 2011
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Kurzawińska, Halina, and Mazur Stanisław. "The effect of bio-preparations on the infestation of tubers by Streptomyces spp." Folia Horticulturae 20, no. 2 (2008): 103–10. http://dx.doi.org/10.2478/fhort-2013-0119.
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Abstract The effect of tuber dressing and plant spraying with Polyversum (B.A.S. Pythium oligandrum) and Biochikol 020 PC (B.A.S. chitosan) bio-preparations on the infestation of potatoe tubers by Streptomyces spp. was studied during the 2005-2007 years. The Vitavax 2000 FS (B.A.S. karboxin and thiuram) was used as a standard fungicide. The results received from field experiments indicate that, during all years of study these preparations significantly reduced tubers infestation by Streptomyces spp. The Polyversum bio-preparation, which was applied to tuber dressing and sprayed on plants four times during vegetation period, showed the best protective effect against Streptomyces spp.
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Mensah Espère, Houngo Ame, Tchabi Atti, and Olowotche Nicolas. "Evaluation of the Potential for Controlling Yam (Dioscorea spp.) Nematodes during the Production Phase using Wrap and Plant Technology and its Effect on Yield in Three Agro-Ecological Zones of Togo." International Journal of Current Microbiology and Applied Sciences 13, no. 10 (2024): 185–97. https://doi.org/10.20546/ijcmas.2024.1310.023.
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Yam, a key food crop in Togo and tropical Africa, faces increasing threats from plant-parasitic nematodes such as Scutellonema bradys, Pratylenchus coffeae, and Meloidogyne incognita, which damage tubers and reduce yields. This study evaluates the efficacy of the "Wrap and Plant" technology, involving abamectin-impregnated banana paper, to mitigate nematode impacts on yam crops across 18 sites in three agro-ecological zones. Three treatments were tested: T1 (abamectin-treated matrices), T2 (untreated matrices), and T3 (traditional practices). Parameters assessed included sprouting rates, tuber weight, and nematode density in tubers, roots, and soil. Results showed no significant differences in sprouting rates or tuber weight across treatments and zones. However, significant differences were noted in AEZ I for nematode density in roots (P = 0.02) and tubers (P = 0.01), with T1 and T2 reducing nematode numbers in AEZ I and II. In AEZ III, traditional practices (T3) were more effective. The nematodes identified included Pratylenchus spp., Scutellonema spp., Meloidogyne spp., and Rotylenchus spp. The effectiveness of the technology varied by zone, showing promise under specific conditions, while traditional methods sometimes outperformed it.
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Širić, Ivan, and Snježana Širol. "Mogućnosti uzgoja tartufa (Tuber spp.)." Glasnik zaštite bilja 42, no. 6 (2019): 38–47. http://dx.doi.org/10.31727/gzb.42.6.6.
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Cilj ovoga rada je opisati mogućnosti podizanja nasada tartufa te gospodarenje istim. U prvom dijelu rada opisan je tartuf kao gljiva, morfološka i biološka svojstva tartufa te pedoklimatski uvjeti rasta i razvoja. Prikazana su dosadašnja znanja o tartufima koja služe kao podloga razrade programa za njihov uzgoj. Detaljnije su opisani veliki bijeli tartuf te tamnosporni tartuf koji su najzanimljiviji za uzgoj. Također, prikazano je tartufarstvo u Hrvatskoj i svijetu kako bi se ukazalo na značaj te visokovrijedne gljive. Opisan je način obrade tla prije sadnje, plana sadnje te planirani način održavanja plantaže. Temeljem provedenih analiza i proučene literature može se zaključiti kako su određena područja u Hrvatskoj pogodna za uzgoj tartufa sa manjim odstupanjima potrebnih pedoloških uvjeta.
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AWOLOGBI, E., and E. I. HAMADINA. "EARLY INDUCTION OF SPROUTING ON SEED TUBERS OF YAM (Dioscorea spp.) SOON AFTER TUBER INITIATION IN A HYDROPONICS SYSTEM." Experimental Agriculture 52, no. 3 (2015): 405–17. http://dx.doi.org/10.1017/s0014479715000174.
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SUMMARYProlonged inability of yam tubers to sprout/germinate is associated with the expression of tuber dormancy, and the start of dormancy in tubers is linked to the onset of tuber formation. Although the plant hormone, abscisic acid (ABA) is known to regulate the onset and maintenance of dormancy in tubers, there are no known method(s) of inducing shoot growth (sprouting) on seed yam tubers that are harvested at 240 days after vine emergence or earlier. Therefore, this study was conducted to: (1) determine whether the absorption of fluridone, a reputed ABA inhibitor, prior to or during early seed yam tuber formation would induce sprouting, and (2) determine the effect of fluridone on early shoot growth. The study was a 2×4 factorial experiment arranged in a Completely Randomized Design (CRD) with eight treatment combinations replicated three times. Two species of yam with long dormancy durations were used: D. rotundata var TDr 131 and D. alata var TDa 98/01166; and three concentrations of fluridone were tested (30, 50, 100 µM). Young plants (69 days after vine emergence) of TDr 131 and TDa 98/01166 were grown in a coco coir medium hydroponics system using Hoagland's Nutrient Solution, with or without the test fluridone concentrations. In all fluridone treatments, most leaves of both species of yam had 30–90% of their surface bleached while the stems appeared purplish. In both Controls, all the newly formed seed tubers that were harvested at 90 and 104 days after vine emergence were dormant (devoid of any new shoots/sprouts). In contrast, over 70% of the seed tubers that developed in 30 and 100 µM fluridone had at least one new shoot, particularly in TDa 98/01166. The fluridone treatments did not significantly affect tuber weight or vegetative growth parameters like dimensions and number of leaves. This study has shown that the duration from vine emergence of the old tuber to sprouting of the new tuber can be reduced by more than half if young plants absorbed fluridone during early tuber development.
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Adejumobi, Idris I., Paterne A. Agre, Didy O. Onautshu, et al. "Assessment of the Yam Landraces (Dioscorea spp.) of DR Congo for Reactions to Pathological Diseases, Yield Potential, and Tuber Quality Characteristics." Agriculture 12, no. 5 (2022): 599. http://dx.doi.org/10.3390/agriculture12050599.
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Yams (Dioscorea spp.) possess the potential to contribute to food security and poverty alleviation in DR Congo; however, yam production is limited by several constraints, including the lack of yam improvement programs to address challenges relating to yield improvement, resistance to foliar diseases, and post-harvest tuber quality. Identification of a superior genotype for these traits and reservoirs of genes for improvement would guide yams’ improvement. This study aims to evaluate and identify landraces with superior performance for farmers and consumers. We evaluated 191 accessions from six yam species, and significant variation in the performances was observed at p < 0.05. Accessions of D. alata were superior for tuber oxidative browning (−0.01), D. cayenensis for high yield potential (29 t/ha), D. bulbifera for yam mosaic virus (YMV) tolerance (AUDPC = 3.88), and D. rotundata for tuber dry matter content (37%). A high genotypic and phenotypic coefficient of variation (>40) was observed for tuber yield, number of tubers per plots, tuber flesh oxidative browning, and tuber flesh texture. High broad-sense heritability estimates (>60) were similarly observed for all the assessed parameters except number of tubers per plot. Tuber size was identified as the best predictor for tuber yield (b = 2.64, p < 0.001) and tuber dry matter content (b = 2.21, p < 0.001). The study identified twenty stable landrace accessions from three Dioscorea species (D. alata (7); D. cayenensis (2); D. rotundata (11)). These accessions combined high yield potential, high tuber dry matter, high tolerance to YMV and YAD, and low tuber flesh oxidation. The accessions could be considered for the establishment of a yam improvement program in DR Congo.
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Zoteyeva, N. M., and Z. Z. Evdokimova. "Source material from crosses among Solanum L. spp. for potato breeding." Proceedings on applied botany, genetics and breeding 183, no. 4 (2022): 115–21. http://dx.doi.org/10.30901/2227-8834-2022-4-115-121.
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Background. Late blight (agent: Phytophthora infestans (Mont.) de Bary) is one of the most destructive diseases for potato. The climate conditions in the northwest of Russia are very favorable for annual late blight infestation. Spreading of the pathogen leads to significant harvest losses. A promising breeding strategy is to expand the genetic diversity of resistance sources.Materials and methods. Resistance of experimental hybrid clones to late blight, their ability to form tubers under long daylight conditions, and a number of agronomic traits were studied using standard methods.Results. Long-term evaluation data were obtained for original interspecies potato hybrids concerning their resistance to late blight. The hybrids were also assessed for their yield and agronomic tuber characteristics. Some of the produced interspecies hybrids demonstrated field resistance to late blight, high tuber yield, and good agronomic traits. Clones derived from some cross combinations significantly exceeded both parents in tuber yield per plant and tuber size.Conclusions. Crosses between potato cultivars and various late blight resistance sources made it possible to combine in hybrid clones the genes of wild and cultivated Andean species and Solanum tuberosum L. with different pedigrees. Productive hybrid clones with resistance to late blight and good agronomic characteristics promise to become useful material for potato breeding programs.
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Kingsley, Elele. "INVESTIGATION OF PLANT-PARASITIC NEMATODES OF YAM IN SELECTED YAM FARMS IN TWO LOCAL GOVERNMENT AREAS OF RIVERS STATE." Tropical Agrobiodiversity 2, no. 2 (2021): 67–71. http://dx.doi.org/10.26480/trab.02.2021.67.71.
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Investigation of plant-parasitic nematodes of yam in selected yam farms in two Local Government Areas of Rivers State was conducted. A total of 22 yam farms were selected and assessed, 12 from Emohua and 10 from Etche Local Governemnet Areas (LGA). Two tubers of yam ready to be harvested were randomly selected and the soil around it were collected, bagged individually and transported to the laboratory for bioassay. Sieve plate nematode extraction technique was used for extraction of nematodes from the tubers and soil. The purpose of the study was to identify the plant parasitic nematodes that affect yam in the selected zone and likely to predict if nematode was a predisposing agent to yam rot in the study area. The results showed that in Emohua LGA, Meloidogtne spp. with mean population of 90.407±0.543 were the most prevalent species in the soil samples followed by Heterodera spp. with 38.622±0.891 and Pratylenchus spp. with 26.322±0.962 while in the roots and yam tuber Meloidogyne spp. had the most prevalent species with mean population of 69.510±0.907, followed by Scutellonema spp. with 15.651±2.201 and then Ditylenchus spp. with 13.7651±2.644. Also, in Etche LGA, Meloidogyne spp., Tylenchulus spp. and Rotylenchulus spp. had the most prevalent species in the soil with mean populations of 24.920±0.479, 22.426±1.093 and 20.202±0.828 respectively. In the roots and yam tubers, Scutellonema spp., Meloidogyne spp. and Heterodera spp. in that order had the most prevalent species with mean populations of 17.814±0.253, 13.240±0.286 and 10.619±0.401 respectively. Data analysis showed that plant-parasitic nematodes recovered from the soil and roots/yam tuber were statistically significant at P<0.05. These showed that the presence of these plant-parasitic nematodes in the study area suggests that they are important pests of yams even though their presence is not noticed by farmers. They could be attributed to poor yield in yams in the study areas.
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Mansvelt, E. L., and E. Carstens. "Outbreak of Erwinia carotovora on Zantedischia spp. in South Africa." Plant Disease 83, no. 10 (1999): 966. http://dx.doi.org/10.1094/pdis.1999.83.10.966c.
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In South Africa, summer-flowering Arum lilies are grown for the tuber, potted plant, and cut flower markets. In 1998, an outbreak of soft rot was detected on Zantedischia oculata cv. Black Magic and Z. elliottiana plants from several nurseries. Crop losses of up to 25% were incurred. The initial symptom was wilting of leaves. When plants were lifted from the soil, soft rot of the tuber was found. Tuber rot usually developed on one side, and plants developing from affected tubers wilted and died. No discoloration of leaf or tuber tissues was found. Isolations from diseased tissues consistently yielded bacterial colonies that were translucent, white, and glistening and that had entire margins on nutrient agar. Ten representative isolates were chosen for further characterization. Erwinia carotovora subsp. carotovora strain B56 was included as a reference strain. All isolates were gram-negative rods, oxidase and arginine dihydrolase negative, catalase positive, and facultatively anaerobic. They degraded pectate and rotted potato slices but did not hydrolyze starch. All isolates fermented glucose, reduced nitrates to nitrites, and grew at a maximum temperature of 37°C. Isolates produced acids from D(+)-glucose, D(+)-cellobiose, melibiose, amygdalin, L(+)-arabinose, D-mannitol, L(+)-rhamnose, sucrose, ribose, D(-)xylose, and D(-)glucose but not from D-arabinose, D-sorbitol, or maltose. Isolates liquefied gelatin and used citrate, arbutine, esculin, salicin, and cellobiose as the sole carbon source. Pathogenicity to Zantedischia spp. was tested by injection of tubers with an inoculum suspension containing 108 CFU/ml. Control plants were inoculated with sterile distilled water. Inoculated plants were kept in a greenhouse at 24°C. Symptoms developed 2 days after inoculation with the pathogen and appeared to be identical to those observed on diseased material in nurseries. Control plants did not rot. The bacterium was readily reisolated from diseased plants, confirmed to be the inoculated pathogen, and identified as E. carotovora, based on morphological, biochemical, and physiological characteristics and pathogenicity. E. aroideae has been reported to cause soft rot of rhizomes of winter-flowering Arum lilies (Z. aethiopica) in South Africa (1). However, this is the first report of soft rot caused by E. carotovora subsp. carotovora on tubers of Z. oculata and Z. elliottiana plants in South Africa. Reference: (1) V. Wager. 1970. Flower Garden Diseases and Pests. Purnell, Cape Town, South Africa.
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Krejzar, V., J. Mertelík, I. Pánková, K. Kloudová, and V. Kůdela. "Pseudomonas marginalis associated with soft rot of Zantedeschia spp." Plant Protection Science 44, No. 3 (2008): 85–90. http://dx.doi.org/10.17221/16/2008-pps.
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For the first time in the Czech Republic, bacteria identified as <I>Pseudomonas marginalis, Pectobacterium carotovorum</I> subsp. <I>carotovorum</I> and <I>Pseudomonas putida</I> were isolated from tubers of <I>Zantedeschia</I> spp. with symptoms of tuber soft rot. The symptoms occurred on mother tubers as well as on new daughter tubers of different calla lily hybrids with yellow spathe, calla lily cv. Mango with bright orange spathe and <I>Zantedeschia rehmanii</I> with pink spathe. The percentage of diseased plants of the total plants in the plot was around 10%. When inoculated into potato tuber slices, strains of <I>P. marginalis</I> and <I>P. c</I>. subsp.<I> carotovorum</I> produced soft rot. Pectolytic activity of <I>P. marginalis</I> strains was less intensive than that of the <I>P. c.</I> subsp. <I>carotovorum</I> strain. The results confirm that bacterial soft rot of <I>Zantedeschia</I> spp. may have several causes.
Dissertations / Theses on the topic "Tuber spp"
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MONACO, Pamela. "Analysis and characterisation of the microbial communities associated with truffles (Tuber spp.)." Doctoral thesis, Università degli studi del Molise, 2021. http://hdl.handle.net/11695/108022.
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I tartufi sono un gruppo polifiletico di funghi ipogei. I funghi del genere Tuber, i cosiddetti “veri tartufi”, sono ascomiceti ectomicorrizici dell’ordine Pezizales con un ciclo vitale complesso, durante il quale il micelio fungino stabilisce interazioni simbiontiche con le radici di diversi alberi ed arbusti.
Delle oltre 180 specie di Tuber attualmente conosciute, alcune (T. aestivum Vittad., T. borchii Vittad., T. magnatum Picco e T. melanosporum Vittad.) sono molto ricercate sul mercato alimentare per via delle loro straordinarie caratteristiche organolettiche, con un enorme valore commerciale.
È noto che i tartufi ospitano complesse comunità microbiche di batteri, lieviti, funghi filamentosi e virus, con le quali interagiscono sia a livello della micorrizosfera che dell’ascocarpo. Tuttavia, molti aspetti legati alla diversità e al potenziale ruolo dei microrganismi, nonché agli effetti delle interazioni tra comunità microbiche sulla biologia del tartufo sono ancora poco conosciuti. Pertanto, l’obiettivo principale di questo lavoro è stato quello di analizzare e caratterizzare le comunità batteriche associate a due delle specie di Tuber di maggiore interesse commerciale: T. aestivum, tartufo nero estivo, e T. magnatum, tartufo bianco pregiato.
Le analisi sono state condotte su ascocarpi raccolti in Molise (Italia centro-meridionale), una delle regioni italiane a più alta vocazione tartufigena (circa il 40% della produzione nazionale di tartufo). Tuttavia, ad oggi, il tartufo molisano ha ricevuto pochissima attenzione dal punto di vista scientifico e, di conseguenza, non è opportunamente valorizzato e tutelato. Le attività di ricerca illustrate nella presente tesi gettano quindi le basi per colmare la carenza di informazioni scientifiche sul tartufo molisano, rappresentando un importante punto di partenza per un’ulteriore e più approfondita caratterizzazione di questa risorsa fondamentale per l’economia locale.
Nello specifico, in un primo studio, sono state analizzate le comunità microbiche associate a sei corpi fruttiferi di T. aestivum e a sei campioni di suolo raccolti nei pressi del Comune di Vastogirardi (Isernia), mediante sequenziamento degli ampliconi del gene codificante per l’rRNA 16S. In linea con i risultati ottenuti in altre ricerche, i principali phyla rinvenuti negli ascocarpi sono stati Proteobacteria ed Actinobacteria, con il genere Bradyrhizobium particolarmente rappresentato. Ciononostante, sono state osservate considerevoli differenze tra il microbiota del suolo e del tartufo ed un’inaspettata eterogeneità in termini di composizione, abbondanza relativa dei principali taxa ed α-diversità all’interno delle comunità microbiche del tartufo.
Nelle altre due ricerche presentate sono state considerate due popolazioni di T. magnatum provenienti da diverse aree della regione Molise. Nel complesso, 21 tartufi bianchi sono stati caratterizzati da un punto di vista morfologico, genetico e microbiologico. Le indagini morfologiche hanno riguardato lo spessore del peridio (parametro per il quale non erano disponibili in letteratura scientifica informazioni dettagliate), mentre le analisi genetiche e microbiologiche si sono focalizzate rispettivamente su un marcatore a singolo locus (SCAR A21-inf) e sulle comunità batteriche della gleba. È emersa una notevole variabilità tra e all’interno delle popolazioni di T. magnatum esaminate, a conferma di un’interessante eterogeneità dei tartufi molisani che li rende ideali per studi più approfonditi.<br>Truffles are a polyphyletic group of fungi whose fruiting bodies sequester their spores and develop underground. Fungi of the genus Tuber, the so-called “true truffles”, are ectomycorrhizal ascomycetes of the Pezizales order that undertake a complex life cycle, during which the fungal mycelium establishes symbiotic associations with the roots of several trees and shrubs.
Some of the more than 180 Tuber species currently known (including T. aestivum Vittad., T. borchii Vittad., T. magnatum Picco, and T. melanosporum Vittad.) are highly sought after on the food market due to their unique organoleptic properties, with a huge commercial value.
It is known that truffles harbour complex microbial communities of bacteria, yeasts, guest filamentous fungi, and viruses, with whom they interact both in the mycorrhizosphere and in the ascocarp. However, many aspects related to the diversity and the potential role of truffle-associated microorganisms, as well as the effects of the interactions among microbial communities on the biology of truffles are still poorly understood. Accordingly, the main purpose of this work was to analyse and characterise the bacterial communities associated with two of the most commercially relevant truffle species: the summer black truffle T. aestivum and the prized white truffle T. magnatum.
Analyses were carried out on Tuber ascomata from Molise region (Central-Southern Italy), one of the most important Italian areas suited to truffle collection (about 40% of the national production). Nevertheless, to date, Molise truffle has received very little attention from a scientific perspective and, consequently, it is not adequately valorised and preserved. Thus, the research activities illustrated in the present thesis lay the foundation to fill the lack of scientific data on the Molise truffles, representing an essential starting point for a further and more in-depth characterisation of this resource of utmost importance for the local economy.
In detail, in a first study, the microbial communities associated with six T. aestivum ascomata and six soil samples collected in the municipality of Vastogirardi (Isernia province) were examined using the 16S rRNA gene amplicon high-throughput sequencing. Consistently with previous researches, the main phyla retrieved in the investigated ascocarps were Proteobacteria and Actinobacteria, with the genus Bradyrhizobium particularly represented. Nonetheless, considerable differences between soil and truffle microbiota and an unexpected heterogeneity within the truffle bacterial communities in terms of composition, relative abundance of the main taxa, and α-diversity values were observed.
The other two reported researches focused on T. magnatum populations from different areas of Molise region. Overall, twenty-one white truffles were characterised from a morphological, genetic, and microbiological point of view. In particular, morphological investigations concerned the thickness of the peridium, a parameter for which no comprehensive information was available, whereas genetic and microbiological analyses focused on the Sequence-Characterised Amplified Region SCAR A21-inf (a single locus marker) and the gleba bacterial communities, respectively. A considerable variability between and within the examined T. magnatum groups emerged, confirming an interesting heterogeneity of Molise truffle populations that makes them ideal for further in-depth studies.
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au, Lynleys@calm wa gov, and Lynley M. Stone. "Floral Biology and Propagation of Blue-Flowered Conospermum Spp." Murdoch University, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040824.145625.
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Blue-flowered Conospermum are endemic to Western Australia, and show great potential as cut flowers. Propagation from cuttings or seed proved difficult, and root initiation in vitro is problematic. This thesis examines the floral biology of the species and the possibility of using somatic embryogenesis to overcome propagation problems.
A survey of explant tissue types for C. eatoniae and C. caeruleum was carried out to identify tissue that could be induced into embryogenic pathways. Vegetative, semi-floral and floral buds were initiated into culture from February to June, but were found unsuitable for embryogenesis, producing shoots, callus or dying in culture. Leaves from in vitro leaf cultures formed callus in the presence of 2,4-D and BAP, but were unable to differentiate into embryos in the presence of a variety of growth regulator combinations and concentrations. Immature zygotes died in culture. Direct embryogenesis and/or embryogenic callus was observed on mature zygotes of the species C. caeruleum, C. spectabile, C. dorrienii and C. brownii, and somatic embryos were maintained in culture for up to 18 months for C. caeruleum.
Maturation and germination of somatic embryos proved difficult; treatments of cold, ABA, desiccation or mannitol did not induce maturation. It appears that developmental pathways in Conospermum are well defined and are difficult to alter in vitro. It was concluded that somatic embryogenesis has limited commercial potential in these species.
Conospermum species have an active pollination mechanism where the style is held in a state of tension when the flower opens. When pressure is applied at the base of the style by an insect, the style flicks downwards, striking the insect pollinator and releasing pollen from the anther in a single dusty mass. However, the breeding systems of blue-flowered Conospermum have not previously been well explored.
Flowers on a C. eatoniae inflorescence opened from the basal end upwards acropetally, with the terminal two or three buds never opening. Fruit and seed set occurred only from the basal one to three buds. Isolation of C. eatoniae and C. amoenum flowers showed they were unable to self-pollinate in the absence of insect pollinators.
Experiments to determine the timing of the peak of stigmatic receptiveness were inconclusive. Pollen germinated and penetrated the stigma 0 ¡V 6 days after anther dehiscence. Pollen loads on the stigma did not relate to the number of pollen tubes observed down the style. Controlled pollinations of cultivated C. eatoniae at a field station using self and cross pollen, revealed compatibility with a range of pollen genotypes, as pollen tubes were observed extending down the style. However, late-acting incompatibility could not be ruled out as controlled crosses failed to set any seed as flowers were shed from the bush.
DNA analysis of open pollinated C. eatoniae seed progeny from two plants from a field station and two plants in natural bushland revealed very different pollination habits. Plants from the field station showed no outcrossing, with progeny closely resembling the maternal parent, whereas plants from the wild population showed outcrossing with several different paternal parents. These results suggest self-pollinated seed can be reliably obtained in a plantation situation using stands of ramets of the same clone. Alternatively, assuming that the required insect pollinators are present in a cultivated stand, it should be possible to obtain cross pollinated seed by surrounding the maternal plant with the desired paternal parent.
Unusual pollen behaviour was observed for many blue-flowered species, a white-flowered species of Conospermum, and close relative, Synaphea petiolaris. Up to three pollen tubes emerged from the triporate pollen in vitro, and at rates of up to 55 Ýms-1. This rate was maintained for only 2 s but is greater than 20 times faster than reported in the literature for any species, in vitro or in vivo. Pollen with multiple tubes was also observed on the stigma in vivo in C. amoenum flowers.
Changing the osmotic pressure of the germination medium by altering sucrose concentration influenced the number of tubes to emerge from the pollen grain; generally the number of tubes decreased as sucrose increased. However, the rate of tube growth was unaffected. The addition of calcium channel blockers to the germination medium had no effect on Conospermum growth rate, nor did they eliminate pulses of tube growth.
Observation of Conospermum pollen ultrastructure revealed similarities to Gramineae pollen. The tube cytoplasm was packed with vesicles filled with material of similar electron density to the cell wall. Few golgi were identified, and the apical end of the tube contained these vesicles, smaller secretory vesicles and mitochondria. This is atypical of the tip, which is normally free of large vesicles. Distinct zones in the cytoplasm were not identified, which is similar to Gramineae. Like the grasses, Conospermum appears to pre-manufacture cell wall material and store it in vesicles ready for rapid germination and extension.
A biological function of multiple pollen tube emergence with such rapid growth was not elucidated.
This research has shown Conospermum to be a complex and very interesting genus. Further investigation into the remarkable growth of multiple pollen tubes would enhance our knowledge of the biological processes involved in tube growth and the process of fast wall formation. The potential benefits to the cut flower industry of commercialising some of these species warrants further effort to find an efficient method of propagation. Introduction into horticulture may be the only means by which these threatened species will survive.
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Kwoseh, Charles Kodia. "Identification of resistance to major nematode pests of yams (Dioscorea spp.) in West Africa." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340023.
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Arzaghi, Mandana. "Nouveau procédé d'hyperdéformation pour les tubes." Thesis, Metz, 2010. http://www.theses.fr/2010METZ031S.
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La nouvelle technique d'hyperdéformation nommée High Pressure Tube Twisting (HPTT), est un procédé continu d'affinement du grain pour les matériaux métalliques avec la géométrie tubulaire. Il consiste à placer un mandrin dans le tube avant d'appliquer une compression axiale directement sur le tube confiné des deux côtés pour produire une pression hydrostatique importante. Le tube est ensuite cisaillé par un couple externe à l'aide de la force de frottement généré par la pression hydrostatique. Les structures ultrafines produit avec HPTT ont été confirmés par MET et leur propriétés mécaniques ont été évaluées. La limite d'élasticité est augmentée de façon monotone avec la déformation imposée par HPTT. L'évolution de la microstructure est étudiée par la technique EBSD et les mesures de texture ont été réalisées avec des rayons X. Les échantillons déformés ont la texture de cisaillement simple, avec des intensités relativement faibles et l'effet de la texture initiale sur la texture finale persiste jusqu'à un cisaillement de 6. La distribution des désorientations entre les grains est bimodale et le second pic augmente avec la déformation. Application industrielle de cette nouvelle technique SPD exige la modélisation avancée en termes d'évolution de texture et le processus de fragmentation des grains. Dans ce but, le nouveau modèle de fragmentation du grain proposé par Toth et al. a été utilisée. L'affinement du grain améliore les résultats de simulation texture de façon significative et donne des informations complémentaires sur la distribution et la taille moyenne des grains, et la distribution de désorientation qui peut être directement comparés aux résultats expérimentaux<br>The new severe plastic deformation (SPD) technique, designated as high pressure tube twisting (HPTT), is a continuous process for grain refinement in bulk metallic materials with tubular geometry. It consists of placing a mandrel into the tube before applying an axial compression directly on the tube confined on both sides to produce high hydrostatic pressure. The tube is then twisted by an external torque with the help of the friction force genrated by the hydrostatic pressure. The ultra-fine grained structures produced with HPTT were confirmed using transmission electron microscopy and their microstructure and mechanical properties were evaluated. The value of yield stress is increased monotonically with the deformation imposed by HPTT. Meanwhile, the inverse deformation path is proved to be less advantageous. Microstructural evolution is studied by EBSD technique and texture measurements were carried out using X-ray. Deformed samples have simple shear texture with relatively low intensities and the effect of the initial texture on the final texture persists up to shear strain of nearly 6. Grain-to-grain misorientation distribution functions are bimodal and the second pick become higher with increasing strain. Industrial application of this new SPD technique requires advanced modelling in terms of texture evolution and grain fragmentation process. For this purpose, the new grain refinement model proposed by Toth and al. was used. Grain refinement improves the texture simulation results significantly and gives information on the average grain size, grain size distribution and misorientation distribution function that can be directly compared to experimental results
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Peuvel, Isabelle. "Les protéines du tube polaire chez Encephalitozoon SPP : caractérisation, polymorphisme et étude des interactions protéiques." Lille 2, 2002. http://www.theses.fr/2002LIL2MT06.
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Arneiro, Lidia Carolina Meira [UNESP]. "Avaliação da influência do caráter lignotúber sobre características silviculturais em testes de progênies de Eucalyptus spp." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/139340.
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000863925.pdf: 1291594 bytes, checksum: deb5e65e57e298b3299eb33c094e853a (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>O Brasil destaca-se dentro do setor florestal quanto ao desenvolvimento e produção de espécies de interesse econômico. Em parceria com empresas do ramo florestal, a Universidade Estadual Paulista (UNESP - Campus de Botucatu) vem desenvolvendo projetos de identificação de características relacionadas ao estresse abiótico em eucalipto. A presença de lignotúber é um caráter que confere a essas espécies maior tolerância a níveis de estresse. Os objetivos deste estudo foram: compreender a relação do lignotúber com o estresse e as características silviculturais por meio das estimativas de correlações fenotípicas e parâmetros genéticos. Os experimentos foram conduzidos com duas espécies de eucaliptos e seus híbridos, em dois ambientes contrastantes quanto aos aspectos edafoclimáticos. Avaliaram-se dois caracteres de crescimento: altura (ALT) e circunferência à altura do peito (CAP) e a presença de lignotúber. De posse dos parâmetros genéticos estimados, não foi detectada manifestação de heterose e epistasia nos materiais em questão. As análises conjuntas dos experimentos indicaram significância para os tratamentos, quanto a presença de lignotubérculo. Deste modo, a correlação fenotípica foi significativa, indicando que na presença de estresse biótico/abiótico existe a associação entre as características silviculturais e a presença de lignotúber. As plantas que apresentaram esta estrutura possuem menor crescimento vegetativo. Estes resultados evidenciam que o lignotúber é uma estrutura de grande importância nas plantas e fator determinante na escolha de genótipos para regiões onde o estresse é alto<br>Brazil stands out in the forest sector by the development and production of species with economic interests. In partnership with forestry companies, the University of Sao Paulo State (UNESP- Botucatu) has been developing studies to identifying traits related to abiotic stress in Eucalyptus. The presence of lignotuber is a character that gives to these species tolerance to different levels of stress. Our aim was to understand the relationship of lignotuber with stress and silvicultural characteristics by estimating the genetic parameters and phenotypic correlations. Experiments were conducted with two eucalyptus species and their hybrids in two contrasting environments as the edaphoclimatic aspects. We evaluated two characters of growth: height (ALT), circumference at breast height (CAP) and presence of lignotuber. The estimation of the genetic parameters did not detect heterosis and epistasis in these materials. Joint analysis of the experiments indicated significance for the treatments, as for the presence of lignotubercle. Thus, the phenotypic correlation was significant, indicating that in the presence of biotic/abiotic stress, exist association between silvicultural traits and the presence of lignotuber. Plants with this structure showed less vegetative growth. These results show that the lignotuber is an important structure in plants and an important factor to be considered in choosing genotypes for regions where stress is high
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Arneiro, Lidia Carolina Meira. "Avaliação da influência do caráter lignotúber sobre características silviculturais em testes de progênies de Eucalyptus spp. /." Botucatu, 2015. http://hdl.handle.net/11449/139340.
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Orientador: Celso Luis Marino<br>Banca: Douglas Domingues da Silva<br>Banca: Evandro Wagner Tambarussi<br>Banca: Mario Teixeira Moraes<br>Banca: Iraê Amaral Guerrini<br>Resumo: O Brasil destaca-se dentro do setor florestal quanto ao desenvolvimento e produção de espécies de interesse econômico. Em parceria com empresas do ramo florestal, a Universidade Estadual Paulista (UNESP - Campus de Botucatu) vem desenvolvendo projetos de identificação de características relacionadas ao estresse abiótico em eucalipto. A presença de lignotúber é um caráter que confere a essas espécies maior tolerância a níveis de estresse. Os objetivos deste estudo foram: compreender a relação do lignotúber com o estresse e as características silviculturais por meio das estimativas de correlações fenotípicas e parâmetros genéticos. Os experimentos foram conduzidos com duas espécies de eucaliptos e seus híbridos, em dois ambientes contrastantes quanto aos aspectos edafoclimáticos. Avaliaram-se dois caracteres de crescimento: altura (ALT) e circunferência à altura do peito (CAP) e a presença de lignotúber. De posse dos parâmetros genéticos estimados, não foi detectada manifestação de heterose e epistasia nos materiais em questão. As análises conjuntas dos experimentos indicaram significância para os tratamentos, quanto a presença de lignotubérculo. Deste modo, a correlação fenotípica foi significativa, indicando que na presença de estresse biótico/abiótico existe a associação entre as características silviculturais e a presença de lignotúber. As plantas que apresentaram esta estrutura possuem menor crescimento vegetativo. Estes resultados evidenciam que o lignotúber é uma estrutura de grande importância nas plantas e fator determinante na escolha de genótipos para regiões onde o estresse é alto<br>Abstract: Brazil stands out in the forest sector by the development and production of species with economic interests. In partnership with forestry companies, the University of Sao Paulo State (UNESP- Botucatu) has been developing studies to identifying traits related to abiotic stress in Eucalyptus. The presence of lignotuber is a character that gives to these species tolerance to different levels of stress. Our aim was to understand the relationship of lignotuber with stress and silvicultural characteristics by estimating the genetic parameters and phenotypic correlations. Experiments were conducted with two eucalyptus species and their hybrids in two contrasting environments as the edaphoclimatic aspects. We evaluated two characters of growth: height (ALT), circumference at breast height (CAP) and presence of lignotuber. The estimation of the genetic parameters did not detect heterosis and epistasis in these materials. Joint analysis of the experiments indicated significance for the treatments, as for the presence of lignotubercle. Thus, the phenotypic correlation was significant, indicating that in the presence of biotic/abiotic stress, exist association between silvicultural traits and the presence of lignotuber. Plants with this structure showed less vegetative growth. These results show that the lignotuber is an important structure in plants and an important factor to be considered in choosing genotypes for regions where stress is high<br>Doutor
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Zittere, Benjamin D. "Flowpath design of a three-tube valve-less pulse detonation combustor." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Sep/09Sep%5FZittere.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, September 2009.<br>Thesis Advisor(s): Sinibaldi, Jose. "September 2009." Description based on title screen as viewed on November 6, 2009. Author(s) subject terms: PDE Pulse Detonation Engine Side Dump Combustor Recirculation Zone. Includes bibliographical references (p. 51). Also available in print.
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Hehn, Olivier. "Analyse expérimentale et simulation thermomécanique du soudage bout à bout de tubes de polyéthylène." Phd thesis, École Nationale Supérieure des Mines de Paris, 2006. http://pastel.archives-ouvertes.fr/pastel-00002138.
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Ce travail porte sur la compréhension et la simulation numérique des phénomènes thermomécaniques régissant la formation des soudures au cours du procédé de soudage bout à bout de tubes de polyéthylène. Ce procédé consiste à faire fondre les extrémités des tubes et à les plaquer l'un contre l'autre avec une certaine pression pour former la soudure par refroidissement de la matière. Le soudage bout à bout, qui paraît simple a priori, fait intervenir un certain nombre de phénomènes interagissant entre eux. Ainsi, il existe de forts couplages entre la mécanique, la thermique et les changements de phase. Ce manuscrit est composé de trois parties principales. Premièrement, une analyse complète du procédé a été réalisée. Ainsi, les phénomènes thermiques se produisant au cours du procédé, principaux moteurs du soudage, et les déplacements de matière, responsables de la formation du cordon de soudure, ont été étudiés. Ceci a mis en évidence l'importance de la dilatation thermique, notamment lors du chauffage de la matière, mais aussi une cinétique de formation du bourrelet et une thermique complexes (formation d'un plan vertical dans le bourrelet lors du chauffage, importance du rayonnement et de la convection lors du chauffage des tubes). Dans une deuxième partie, nous avons caractérisé la matière dans le but d'obtenir une simulation numérique du procédé la plus réaliste possible. Les lois de fusion et de crisallisation du polyéthylène ont été déterminées à partir des lois d'Avrami et d'Ozawa. Les comportements du polyéthylène à l'état liquide, solide et au cours de la transition ont également été déterminés. De plus, des mesures d'enthalpie de changement de phase et de dilatation thermique ont été faites. Finalement, l'ensemble des étapes du procédé a été simulé à l'aide du logiciel Forge2®, bien adapté à la résolution des problèmes thermiques et mécaniques responsables de la formation des soudures. Les lois et les paramètres obtenus expérimentalement ont été intégrés au logiciel. Les résultats obtenus sont très satisfaisants, tant au niveau de la thermique que du déplacement de matière et de la forme des bourrelets. Nous avons à présent une meilleure compréhension du soudage bout à bout ainsi qu'un premier outil opérationnel pour simuler le procédé.
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Schönhals, Elske Maria [Verfasser], and Christiane [Akademischer Betreuer] Gebhardt. "Identifying novel diagnostic SNP markers for potato (Solanum tuberosum L.) tuber starch and yield by association mapping / Elske Maria Schönhals. Gutachter: Christiane Gebhardt." Köln : Universitäts- und Stadtbibliothek Köln, 2014. http://d-nb.info/1054420394/34.
Full textBooks on the topic "Tuber spp"
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Zambonelli, Alessandra, Mirco Iotti, and Claude Murat, eds. True Truffle (Tuber spp.) in the World. Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-31436-5.
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Black, Michael Bruce. Genetic (allozyme) variation in Vestimentifera (Ridgeia spp.) from hydrothermal vents of the Juan de Fuca Ridge (northeast Pacific Ocean). National Library of Canada, 1991.
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Beattie, R. Mark, Anil Dhawan, and John W.L. Puntis. Enteral nutritional support. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780198569862.003.0010.
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Access routes for enteral tube feeding 73Complications of enteral nutritional support 76Liquid feed composition and choice of feed 78Assessment of a patient needing nutritional support will include a decision regarding the most appropriate method of feeding. The enteral route is preferred for children who have an adequately functioning gastrointestinal tract. Oral intake can simply be increased by use of food fortification, sip feeds, or energy supplements. If oral intake is poor or contraindicated, tube feeding may be used....
Book chapters on the topic "Tuber spp"
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Reddy, P. Parvatha. "Yams, Dioscorea spp." In Plant Protection in Tropical Root and Tuber Crops. Springer India, 2015. http://dx.doi.org/10.1007/978-81-322-2389-4_5.
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Moorthy, S. N., M. S. Sajeev, R. P. K. Ambrose, and R. J. Anish. "Other starches." In Tropical tuber starches: structural and functional characteristics. CABI, 2021. http://dx.doi.org/10.1079/9781786394811.0159.
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Abstract This chapter discusses the extraction, physiochemical (chemical composition, amylose and amylopectin content), structural (granular morphology, X-ray diffraction pattern, starch crystallinity, and amylose and amylopectin structure), functional (swelling pattern, solubility, viscosity, rheological properties and retrogradation) and thermal properties, and digestibility of starches from minor tuber crops (e.g., arrowroot, Curcuma spp., Canna edulis [C. indica], Chinese water chestnut [Eleocharis dulcis], chayote [Sechium edule], Pachyrhizus ahipa, Oxalis tuberosa, Arracacia xanthorrhiza, Lilium spp.).
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Claudius-Cole, Abiodun. "Importance and integrated nematode management of the yam nematode (Scutellonema bradys) in yam cropping systems of West Africa." In Integrated nematode management: state-of-the-art and visions for the future. CABI, 2021. http://dx.doi.org/10.1079/9781789247541.0052.
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Abstract Yam, Dioscorea spp., one of the oldest food crops known to humans, is the fourth most important root and tuber crop globally. It is a tropical plant that provides food and income for the people in the regions where it is grown. Major nematode pests reported on yams include Scutellonema bradys, Meloidogyne spp., Pratylenchus spp. and Rotylenchulus reniformis. This chapter addresses S. bradys, causing dry rot disease of yams in field and storage. When S. bradys infected seed tubers are planted, plant survival is reduced, and the speed of the disease cycle is amplified leading to reduced yield. The economic importance, host range, distribution, damage symptoms, biology and life cycle, interactions with other nematodes and pathogens, recommended integrated nematode management, and management optimization of S. bradys are discussed. Future research requirements and developments are also mentioned.
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Fan, Yong-jun, Fa-Hu Li, Yan-Lin Zhao, and Wei Yan. "The Method Research on Tuber spp. DNA in Soil." In Lecture Notes in Electrical Engineering. Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-7618-0_390.
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Riccioni, Claudia, Andrea Rubini, Beatrice Belfiori, Gianluigi Gregori, and Francesco Paolocci. "Tuber magnatum: The Special One. What Makes It so Different from the Other Tuber spp.?" In Soil Biology. Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-31436-5_6.
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Bakker, Peter A. H. M., Albert W. Bakker, F. Patrick Geels, Jan G. Lamers, and Bob Schippers. "Increase of Potato Tuber Yields in Short Rotations of Potato by Seed Tuber Treatments with Fluorescent Pseudomonas spp." In Effects of Crop Rotation on Potato Production in the Temperate Zones. Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-2474-1_14.
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Taïbi, Khaled, Leila Aït Abderrahim, Mohamed Boussaid, et al. "Phylogeny, Phytochemistry, Traditional Uses and Pharmaceutical Properties of Thapsia spp. Roots." In Medicinal Roots and Tubers for Pharmaceutical and Commercial Applications. CRC Press, 2023. http://dx.doi.org/10.1201/b22924-6.
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Diebolder, Christoph A., Rebecca S. Dillard, and Ludovic Renault. "From Tube to Structure: SPA Cryo-EM Workflow Using Apoferritin as an Example." In Methods in Molecular Biology. Springer US, 2021. http://dx.doi.org/10.1007/978-1-0716-1406-8_12.
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Chen, Mengjun, Fu-Shen Zhang, and Jianxin Zhu. "Leaching Toxicity of Pb and Ba Containing in Cathode Ray Tube Glasses by SEP-TCLP." In Recycling of Electronic Waste II. John Wiley & Sons, Inc., 2011. http://dx.doi.org/10.1002/9781118086391.ch15.
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Trangoni, Marcos D., Andrea K. Gioffré, and Silvio L. Cravero. "A Closed-tube Loop-Mediated Isothermal Amplification Assay for the Visual Endpoint Detection of Brucella spp. and Mycobacterium avium subsp. paratuberculosis." In Methods in Molecular Biology. Springer New York, 2017. http://dx.doi.org/10.1007/978-1-4939-7037-7_14.
Full textConference papers on the topic "Tuber spp"
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Prateek, Mr, Shubham Tomar, Shivani Tanwar, Ajay Kumar, and Kapil Saini. "IDM STRATEGIES FOR MANAGING POTATO CROP DISEASES IN KEY REGIONS OF UTTAR PRADESH." In MODERN AGRICULTURE: INNOVATIONS AND SUSTAINABILITY FOR A RESILIENT FUTURE. Anu Books, 2024. https://doi.org/10.31995/book.ab334.a25.chapter3.
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Solanum tuberosum L., or potato, is one of the world's most important staple crops, and India ranks at the second position in the list after China. At the state level, Uttar Pradesh is on the first position with 15,812.62 thousand metric tons during 2018-19. Potato crop from the region is, however, severely affected by soil-and-tuber-borne diseases and pests. IDM is one of the major approaches taken for the protection of potato crops in Uttar Pradesh that would balance disease control with sustainability and reduced chemical dependency. IDM integrates cultural, biological, physical, and chemical strategies, encompassing crop rotation, intercropping, and the use of disease-free seed strains. It includes beneficial microorganisms like Trichoderma spp., Pseudomonas spp. and the group of bacteria are the most potent in controlling pathogens such as Rhizoctonia solani, which maintains healthy soils and reduces the reliance on chemical pesticides. A critical review is done by including IDM practices such as the early warning system along with judicious use of fungicides to avoid yield loss. Initiatives of the Government, programs for training of farmers and implementation of advanced technologies, including drone monitoring, with regard to their role in improving the effectiveness of IDM. IDM enhances not only productivity and quality of potatoes but also enhances sustainability of livelihood and environment. Taken together, it offers one avenue through which safe and healthy potatoes can be produced in the agricultural sector of the state of Uttar Pradesh as a way to promote food security.
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Yousef, Khaled, Abebayehu Assefa, Ahmed Hegazy, and Abraham Engeda. "Comparative Study of Using Water and R-134a as Cooling Medium in the Condenser of a Steam Power Plant." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-25034.
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This paper presents a comparative analytical study of using water and R-134a as cooling medium in the condenser of a steam power plant (SPP). In this study, a shell-and-tube cross-flow heat exchanger has been considered. Because of its direct effect on cycle thermal efficiency, the condenser of the SPP has been continuously improved over the years. One of the ways of increasing the performance of a SPP is by reducing the condenser pressure and using low temperature cooling medium in the condenser. The lower the temperature of the cooling fluid circulating through the condenser tubes, the faster will be the steam condensation. This process increases the condensation rate as well as condenser heat transfer rate. Refrigerants have much lower temperatures and much higher heat transfer rates than water. In this comparative study of using R-134a or water as a cooling fluid in the condenser of a SPP, steam enters the shell side of a single-pass horizontal condenser and the condensate is collected at the bottom. Cooling fluid, “water or R-134a”, is fed into the tubes. The results of the analytical study indicated higher condensation rates and heat transfer for R-134a than water. Moreover, the exergetic and exergy efficiency analysis revealed that R-134a has higher values than water, which increase the power plant thermal efficiency and reduce the condenser size.
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Onyango Awuor, Silas Onyango Awuor. "Long-term Home Enteral Nutrition: Feeding Tube-related Complications and Problems in old age Patients." In 4th International Nutrition and Dietetics Scientific Conference. KENYA NUTRITIONISTS AND DIETICIANS INSTITUTE, 2024. http://dx.doi.org/10.57039/jnd-conf-abt-2024-gioh-06.
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The highest infusion therapy at home nowadays is tube feeding or Home enteral Nutrition (HEN) normally used in patient who have a functional gastrointestinal tract but are unable to meet their nutrient requirement through oral intake. This study aim was to evaluate the long-term complications, pathogens and problems related to gastrostomy and jejunostomy feeding tubes used for home enteral nutrition support and the effect these have on health care use. This was retrospectively study among 50 patients (28 having gastrostomy and 22 with jejunostomy) who have been discharged on long-term (>2 months) enteral nutrition and followed up at regular intervals by a nurse. Data were collected and analyzed on complication associated with tube feeding as well as the intervention for a period of six months. From this study it was found that 28 (55.1%) of the participant frequently removes the tube, 23 (46.6%) tube leakage, and 18 (36.4%) had dermatitis of the stoma. Some of the patient 8 (16.4%) developed diarrhea which was seen due to pathogens causing diarrhoea in which Escherichia coli emerged the highest at 5 (30%) even though it is classified as non-pathogenic organism but can enhance other pathogen infection, followed by Salmonella spp. and Shigella spp. at 4 (25%) and lastly Campylobacter spp. at 2 (12%). From this study it was found that most of our patients receiving long-term home enteral nutrition feeding tube-related complications are frequently expose themselves to common pathogens which may lead to other complication to them. Therefore, further studies are needed to address their optimal prevention modalities and management. Key words: Complications, Gastrostomy, Jejunostomy, pathogens, Home enteral nutrition
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RUI, Zhenglei. "Magnetic pulse-assisted semi-solid brazing of Cu/Al tube joints and oxide film removal mechanism." In Metal Forming 2024. Materials Research Forum LLC, 2024. http://dx.doi.org/10.21741/9781644903254-21.
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Abstract. In this paper, the advantages of magnetic pulse welding, brazing and semi-solid forming are combined to propose magnetic pulse-assisted semi-solid brazing (MPASSB) to join copper and aluminum tubes. Based on 3D electromagnetic-structural-fluid finite element simulations, the high-speed impact of the aluminum tube on the filler metal will drive the high-speed shear rheology of the semi-solid filler metal. Based on 2D FEM-SPH finite element analysis, the aluminum tube will have a strong interaction with the filler metal during the high-speed impact on the filler metal, which is conducive to the removal of the oxide film on the surface of the copper-aluminum tube and the promotion of element diffusion. Microscopic characterization of the joints revealed that the interfacial oxide film had been completely removed, achieving interfacial metallurgical bonding, and no brittle copper-aluminum intermetallic compounds were found at the interface, with a shear strength of 40 MPa.
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Park, Yusun, Byoung Uhn Bae, Jongrok Kim, et al. "Experimental Study on the Safety Injection Pump (SIP) Failure Accompanied by the Steam Generator Tube Rupture (SGTR)." In 2018 26th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icone26-81460.
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The integral effect test to simulate the safety injection pump (SIP) failure accompanied by a steam generator tube rupture (SGTR), named a SGTR-SIP-01 test, was performed to investigate the thermal hydraulic phenomena during a multiple failure accident. In this study, a thermal-hydraulic integral effect facility, ATLAS (Advanced Thermal-hydraulic test Loop for Accident Simulation) was utilized to simulate thermal hydraulic phenomenon which can be occurred in the nuclear power plant, as realistically as possible. In this SGTR-SIP-01 test, a rupture of five steam generator u-tubes on the steam generator hot-side was simulated. Due to the initiation of SGTR, a reactor was tripped by high steam generator level (HSGL) signal. During the transient simulation for SGTR-SIP-01 test, major thermal-hydraulic parameters such as the system pressures, the collapsed water levels, the flows in the primary loops, and the fluid temperatures, were measured and analyzed. Through this experimental result, insights about the accident management procedure can be provided in the case of the multiple failure accident, such as a SGTR accident with a total failure of SIPs. In addition to that, for improvement of the system code which are now on developing such SPACE or MARS-KS code, this test data can be utilized for validation and verification work.
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Quadrini, Fabrizio, Alice Proietti, Leandro Iorio, et al. "OUT-OF-AUTOCLAVE MOLDING OF THICK CARBON FIBER REINFORCED TUBES BY USING SHRINKABLE TUBES." In SAMPE 2025 Indianapolis. Society for the Advancement of Material and Process Engineering, 2025. https://doi.org/10.33599/nasampe/s.25.0121.
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Carbon fiber reinforced (CFR) tubes for aeronautic and aerospace are manufactured by wrapping and autoclave curing. These technologies present technological and cost barriers for the automotive and urban air mobility (UAM) sectors. Autoclave molding is an expensive process because of the time, energy and materials involved. In this study, an out-of-autoclave (OOA) process is proposed by using shape memory polymers (SMPs). Composite tubes have been prototyped by winding CFR prepregs on a rigid mandrel, and agglomeration has been achieved in oven by the pressure of a thermo-shrinkable tube. Final composites have 11, 19 and 26 CFR plies, with thickness from 3.2 mm to 7.2 mm and internal diameter of 28 mm. Ring samples with a width of 15 mm have been cut from the molded samples to observe its section and to perform transverse compressive tests. Defects have been found as wrinkles and porosity, but a good agglomeration has been already reached, and improvements are possible by using vacuum bagging and internal SMP cores. The proposed technology has the potential to manufacture thick CFR tubes by tailoring the consolidation pressure with higher production rate and lower cost than autoclave, as necessary to sustain the future automotive and UAM market.
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Latini, Carolina, Kesavan Govinathan, Philip Wassouf, Samyak Jain, and Raymond Tibbles. "Shunted Gravel Pack Failures – And How to Prevent Them." In SPE Annual Technical Conference and Exhibition. SPE, 2023. http://dx.doi.org/10.2118/214934-ms.
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Abstract The success of any gravel pack treatment implies effective gravel coverage of the screens. Shunt tubes are used in both open and cased hole completions to overcome some of the challenges present for conventional gravel placement techniques by allowing slurry to bypass any premature bridges and continue packing downstream. Shunted gravel packs are therefore viewed as the most forgiving gravel placement technique, which has generated a myth that the use of a shunt tubes "guarantees" a successful gravel pack. However, failures of shunted pack placement are being experienced, resulting in wells that are incompletely packed. A better understanding of the limitations of shunt tube systems and an appropriate engineering design can effectively reduce the risk of shunted gravel pack failures. Case histories are used to present a variety of shunt tube gravel placement failures. Surface and bottom hole gauge data combined with an industry standard sand control simulation software has enabled more detailed evaluation and identification of the different failure mechanisms. These include incomplete packs due to shallow zone fracturing, the blockage of shunt entry due to fluid quality issues and shunts erosion failures, among others. This paper consolidates the various shunted gravel pack failure mechanisms that have been experienced in field operations and makes recommendations on how improved treatment designs can prevent them.
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Koshimizu, Takao, Hiromi Kubota, Yasuyuki Takata, and Takehiro Ito. "Numerical Simulation of Heat and Fluid Flow in a Basic Pulse-Tube Refrigerator." In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56295.
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The working principle of refrigeration in basic pulse-tube refrigerators (BPTR) has been explained by the mechanism called surface heat pumping (SHP) that heat is conveyed from the cold end to the hot end of the pulse tube by the successive heat exchange between the working gas and the wall. In this study, a numerical simulation has been performed to clarify the effect of the wall in BPTRs by comparing the numerical results in two physical models; one is the model considering the heat exchange between the working gas and the wall (HE model), and the other is the model ignoring that (AW model). As a result, the importance in the effect of the wall was shown clearly. In addition, the mechanism of refrigeration other than the SHP was made clear in the AW model.
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Wang, Li, and Hongying Li. "Research on Flow and Condensation of Vapor With Non-Condensable Gas in an Inclined Tube." In ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference collocated with the ASME 2007 InterPACK Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ht2007-32614.
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A set of separate heat pipe (SHP) with water as medium has been built in this paper. The flow and condensation of vapor with non-condensable and high partial pressure air in the SHP are measured in the experiment. A series studies are made of the effect on the parameters-coolant water flux, vapor flux, the coolant inlet temperature and the inlet vapor temperature and a lot of reliable data are obtained to analyze the heat transfer process.The physical model of the flow and condensation of vapor-air mixture has been studied and the related numeral model is founded by using the two-fluid model in the Mathematical model. The numerical result agrees well with the experimental data.
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Gajadhar, Ahiliah, and Raffie Hosein. "Design of a Solar Parabolic Trough Capable of Producing Steam for Enhanced Oil Recovery in Trinidad and Tobago." In SPE Canadian Energy Technology Conference. SPE, 2022. http://dx.doi.org/10.2118/208903-ms.
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Abstract Enhanced oil recovery by steam injection requires the burning of natural gas, a finite and expensive resource for steam production. However, solar energy can be harnessed for steam production via solar parabolic troughs. In this study, the design and application of a solar parabolic trough, in tandem with a heat exchanger for producing steam for Enhanced Oil Recovery (EOR) in Trinidad and Tobago is presented. Excel spreadsheets were developed to perform the calculations and to optimize the size and design of the parabolic trough collector for maximum heating efficiency. The parabolic trough designed was 36 m in length and consisted of a parabolic aluminum reflector, stainless steel receiver tube, and a glass envelope that surrounded the receiver tube. The heat transfer fluid used was Therminol VP-1, a synthetic oil, which was heated up to 403 °C. Once heated, the heat transfer fluid was then transferred to a heat exchanger whereby steam was produced at 300°C. Overall, 4 of the parabolic trough collector systems were required to heat enough fluid to fill the calculated 343 tubes of the heat exchanger, which were 0.091 m in diameter and 4.9m in length. The total cost of the parabolic troughs and the heat exchanger tubes was calculated to be USD 119,562. By having a mass flow rate of 46 kg/s for the water within the heat exchanger, approximately 1630 barrels of oil were economically produced at a maximum steam oil ratio of 4.5 after one day of steam injection. A cash flow projection was completed using both operational and capital expenditure of the parabolic trough collector. From this study, the parabolic trough system was shown to generate a profit of USD 1.8 MM after six months of steam injection. Profit calculation considered both capital and operating expenditure as well as the income gained from oil recovery due to the parabolic trough collector. The spreadsheet developed can be used to design similar systems of steam generation for enhanced oil recovery projects of different scales.
Reports on the topic "Tuber spp"
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Shomer, Ilan, Ruth E. Stark, Victor Gaba, and James D. Batteas. Understanding the hardening syndrome of potato (Solanum tuberosum L.) tuber tissue to eliminate textural defects in fresh and fresh-peeled/cut products. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7587238.bard.
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The project sought to understand factors and mechanisms involved in the hardening of potato tubers. This syndrome inhibits heat softening due to intercellular adhesion (ICA) strengthening, compromising the marketing of industrially processed potatoes, particularly fresh peeled-cut or frozen tubers. However, ICA strengthening occurs under conditions which are inconsistent with the current ideas that relate it to Ca-pectate following pectin methyl esterase (PME) activity or to formation of rhamnogalacturonan (RG)-II-borate. First, it was necessary to induce strengthening of the middle lamellar complex (MLX) and the ICA as a stress response in some plant parenchyma. As normally this syndrome does not occur uniformly enough to study it, we devised an efficient model in which ICA-strengthening is induced consistently under simulated stress by short-chain, linear, mono-carboxylic acid molecules (OAM), at 65 oC [appendix 1 (Shomer&Kaaber, 2006)]. This rapid strengthening was insufficient for allowing the involved agents assembly to be identifiable; but it enabled us to develop an efficient in vitro system on potato tuber parenchyma slices at 25 ºC for 7 days, whereas unified stress was reliably simulated by OAMs in all the tissue cells. Such consistent ICA-strengthening in vitro was found to be induced according to the unique physicochemical features of each OAM as related to its lipophilicity (Ko/w), pKa, protonated proportion, and carbon chain length by the following parameters: OAM dissociation constant (Kdiss), adsorption affinity constant (KA), number of adsorbed OAMs required for ICA response (cooperativity factor) and the water-induced ICA (ICAwater). Notably, ICA-strengthening is accompanied by cell sap leakage, reflecting cell membrane rupture. In vitro, stress simulation by OAMs at pH<pKa facilitated the consistent assembly of ICAstrengthening agents, which we were able to characterize for the first time at the molecular level within purified insoluble cell wall of ICA-strengthened tissue. (a) With solid-state NMR, we established the chemical structure and covalent binding to cell walls of suberin-like agents associated exclusively with ICA strengthening [appendix 3 (Yu et al., 2006)]; (b) Using proteomics, 8 isoforms of cell wall-bound patatin (a soluble vacuolar 42-kDa protein) were identified exclusively in ICA-strengthened tissue; (c) With light/electron microscopy, ultrastructural characterization, histochemistry and immunolabeling, we co-localized patatin and pectin in the primary cell wall and prominently in the MLX; (d) determination of cell wall composition (pectin, neutral sugars, Ca-pectate) yielded similar results in both controls and ICA-strengthened tissue, implicating factors other than PME activity, Ca2+ or borate ions; (e) X-ray powder diffraction experiments revealed that the cellulose crystallinity in the cell wall is masked by pectin and neutral sugars (mainly galactan), whereas heat or enzymatic pectin degradation exposed the crystalline cellulose structure. Thus, we found that exclusively in ICA-strengthened tissue, heat-resistant pectin is evident in the presence of patatin and suberinlike agents, where the cellulose crystallinity was more hidden than in fresh control tissue. Conclusions: Stress response ICA-strengthening is simulated consistently by OAMs at pH< pKa, although PME and formation of Ca-pectate and RG-II-borate are inhibited. By contrast, at pH>pKa and particularly at pH 7, ICA-strengthening is mostly inhibited, although PME activity and formation of Ca-pectate or RG-II-borate are known to be facilitated. We found that upon stress, vacuolar patatin is released with cell sap leakage, allowing the patatin to associate with the pectin in both the primary cell wall and the MLX. The stress response also includes formation of covalently bound suberin-like polyesters within the insoluble cell wall. The experiments validated the hypotheses, thus led to a novel picture of the structural and molecular alterations responsible for the textural behavior of potato tuber. These findings represent a breakthrough towards understanding of the hardening syndrome, laying the groundwork for potato-handling strategies that assure textural quality of industrially processed particularly in fresh peeled cut tubers, ready-to-prepare and frozen preserved products.
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Kurm, Viola, and Jan van der Wolf. Report: Resistance of potato tubers against soft rot Pectobacteriaceae (SRP) : Disease resistance in potato tubers against soft rot Pectobacteriaceae. Stichting Wageningen Research, Wageningen Plant Research, Business unit Biointeractions and Plant Health, 2021. http://dx.doi.org/10.18174/563736.
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Macedo, Jorge, Paul Mayne, Sheng Dai, et al. Cone Penetration Testing for Illinois Subsurface Characterization and Geotechnical Design. Illinois Center for Transportation, 2024. http://dx.doi.org/10.36501/0197-9191/24-013.
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This project sets the stage for implementing a cone penetration testing (CPT) practice in the state of Illinois, providing recommendations for using and interpreting CPT soundings in subsurface investigations. This study also contributes to modernizing Illinois Department of Transportation (IDOT) policy to current CPT-related practices adopted in other departments of transportation, which is consistent with recommendations from the Federal Highway Administration. Toward the goals of this project, CPT soundings across the nine districts of the state of Illinois have been conducted, and available CPT data at IDOT have been evaluated. The generated data have been uniformly processed, generating a database of 156 CPTs distributed across the nine districts. The database also includes shear wave velocity profiles at 28 locations and pore pressure dissipation tests at 45 locations. In addition, information (editable and non-editable) provided by IDOT has been carefully examined. The provided information consisted of boreholes with standard penetration test (SPT) data and laboratory tests on collected Shelby tubes. This information has been used to develop SPT-CPT correlations that can be applied in the state of Illinois and to provide examples of interpreting seismic piezocone test (SCPTu) data in the context of laboratory testing. Due to the several independent, fast, and reliable measurements that can be conducted in a CPT sounding and the fact that they can be done cost-effectively, CPT soundings are increasingly being preferred for in situ testing, and their adoption at IDOT is a positive step forward and consistent with the best practices at other U.S. departments of transportation.
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Handa, Avtar K., Yuval Eshdat, Avichai Perl, Bruce A. Watkins, Doron Holland, and David Levy. Enhancing Quality Attributes of Potato and Tomato by Modifying and Controlling their Oxidative Stress Outcome. United States Department of Agriculture, 2004. http://dx.doi.org/10.32747/2004.7586532.bard.
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General The final goal and overall objective of the current research has been to modify lipid hydroperoxidation in order to create desirable phenotypes in two important crops, potato and tomato, which normally are exposed to abiotic stress associated with such oxidation. The specific original objectives were: (i) the roles of lipoxygenase (LOX) and phospholipids hydroperoxide glutathione peroxidase (PHGPx) in regulating endogenous levels of lipid peroxidation in plant tissues; (ii) the effect of modified lipid peroxidation on fruit ripening, tuber quality, crop productivity and abiotic stress tolerance; (iii) the effect of simultaneous reduction of LOX and increase of PHGPx activities on fruit ripening and tuber quality; and (iv) the role of lipid peroxidation on expression of specific genes. We proposed to accomplish the research goal by genetic engineering of the metabolic activities of LOX and PHGPx using regulatable and tissue specific promoters, and study of the relationships between these two consecutive enzymes in the metabolism and catabolism of phospholipids hydroperoxides. USA Significant progress was made in accomplishing all objectives of proposed research. Due to inability to regenerate tomato plants after transforming with 35S-PHGPx chimeric gene construct, the role of low catalase induced oxidative stress instead of PHGPx was evaluated on agronomical performance of tomato plant and fruit quality attributes. Effects of polyamine, that protects DNA from oxidative stress, were also evaluated. The transgenic plants under expressing lipoxygenase (LOX-sup) were crossed with catalase antisense (CAT-anti) plants or polyamine over producing plants (SAM-over) and the lines homozygous for the two transgenes were selected. Agronomical performance of these line showed that low catalase induced oxidative stress negatively affected growth and development of tomato plants and resulted in a massive change in fruit gene expression. These effects of low catalase activity induced oxidative stress, including the massive shift in gene expression, were greatly overcome by the low lipoxygenase activity. Collectively results show that oxidative stress plays significant role in plant growth including the fruit growth. These results also for the first time indicated that a crosstalk between oxidative stress and lipoxygenase regulated processes determine the outcome during plant growth and development. Israel Regarding PHGPx, most of the study has concentrated on the first and the last specific objectives, since it became evident that plant transformation with this gene is not obvious. Following inability to achieve efficient transformation of potato and tomato using a variety of promoters, model plant systems (tobacco and potato cell cultures, tobacco calli and plantlets, and Arabidopsis) were used to establish the factors and to study the obstacles which prohibited the regeneration of plants carrying the genetic machinery for overproduction of PHGPx. Our results clearly demonstrate that while genetic transformation and over-expression of PHGPx occurs in pre-developmental tissue stage (cell culture, calli clusters) or in completed plant (Arabidopsis), it is likely that over-expression of this enzyme before tissue differentiation is leading to a halt of the regeneration process. To support this assumption, experiments, in which genetic engineering of a point-mutated PHGPx gene enable transformation and over-expression in plants of PhSPY modified in its catalytic site and thus inactive enzymatically, were successfully carried out. These combined results strongly suggest, that if in fact, like in animals and as we established in vitro, the plant PHGPx exhibits PH peroxidase activity, these peroxides are vital for the organisms developmental process.
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Schofield, Ian S., Paul L. Brown, Mark J. Logsdon, and Matthew P. Wickham. Waste Rock Dump Characterization Studies at the Bingham Canyon Mine. Utah Geological Survey, 2024. http://dx.doi.org/10.34191/mp-179.
Full textAbstract:
The Bingham Canyon Mine, located near Salt Lake City, Utah, is surrounded by more than 6 billion tons of waste rock developed over the open cut mining history from 1903 to present; the surface area of the waste rock is approximately 5000 acres. Waste rock dumps have a thickness of more than 1 200 feet from crest to toe. From 1930 to 2000, selected portions of the waste rock dumps were commercially leached using a ferric-sulfate-based lixiviant to extract copper, whereas other portions have only received meteoric leaching. From 2011 to present, Rio Tinto Kennecott has studied the evolution and geochemical controls on water chemistry associated with the waste rock dumps at the Bingham Canyon Mine. In this program, the waste rock dumps have been characterized in detail from the field logging of, and data collected from instrumentation installed within, 13 paired borings. At 12 of the 13 locations, the borings penetrated the full depth of the dumps, through the pre-mine soil contact, and into bedrock. Borings were installed to depths approaching 900 feet below ground surface using roto-sonic drilling methods to enable (1) core recovery and (2) measurement of near in situ properties. Field logging of the borings included Unified Soil Classification System descriptions, clast lithology, relative oxidation, paste pH, and geophysical methods (gyroscopic, temperature, neutron, and gamma). Core from the borings was analyzed for geotechnical properties (density, grain size distribution, moisture content, plasticity index and limit, and direct and block shear), quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN), modified acid-base accounting (ABA), modified synthetic precipitation leaching procedure (SPLP), and hyperspectral analysis by CoreScan. If water was encountered during the drilling process at sufficient volumes for collection from the core barrel, samples were collected for chemical analysis. Instrumentation installed within the borings included lysimeters, thermistor nodes, direct temperature sensing (DTS) fiber optic cables, time domain reflectometry (TDR), shear cables, gas (oxygen, carbon dioxide) measurement tubes, and vibrating wire piezometers (VWPs). Additionally, each drill site had multiple measurements of oxygen consumption in the surface layer of the local waste rock. Data acquired from the borings were linked with historical information (covering a period of greater than 50 years) from extensive drilling, mineralogical and litho-geochemical evaluations, hydraulic and tracer testing, and 20 years of seepage f low and water chemistry data to develop a conceptual model that describes the hydraulic, geochemical, and physical behavior of the waste rock dumps. Pyrite and other sulfide minerals in the waste rock dumps are oxidized by both diffusive and convective ingress of air, producing acidic, high-total dissolved solids effluents, and jarosite that has formed within the waste rock as a secondary phase that stores additional acidity. The dominant air ingress mechanism is convection, which accounts for greater than 90% of the sulfide oxidation within the waste rock dumps. Based on temperature profiles and water balance for the dumps, moisture loss to geochemical reactions is a significant part of the water budget.
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Watad, Abed A., Paul Michael Hasegawa, Ray A. Bressan, Alexander Vainstein, and Yigal Elad. Osmotin and Osmotin-Like Proteins as a Novel Source for Phytopathogenic Fungal Resistance in Transgenic Carnation and Tomato Plants. United States Department of Agriculture, 2000. http://dx.doi.org/10.32747/2000.7573992.bard.
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The goal of this project is to enhance fungal resistance of carnation and tomato through the ectopic expression of osmotin and other pathogenesis-related (PR) proteins. The research objectives were to evaluate in vitro antifungal activity of osmotin and osmotin and other PR protein combinations against phytopathogens (including Fusarium oxysporum, Verticillium dahliae, Botrytus cinerea or Phytophthora infestans), develop protocols for efficient transformation of carnation and tomato, express PR proteins in transgenic carnation and tomato and evaluate fungal resistance of transgenic plants. Protocols for microprojectile bombardment and Agrobacterium-mediated transformation of carnation were developed that are applicable for the biotechnology of numerous commercial cultivars. Research established an efficient organogenetic regeneration system, optimized gene delivery and transgene expression and defined parameters requisite to the high frequency recovery of transgenic plants. Additionally, an efficient Agrobacterium-mediated transformation protocol was developed for tomato that is applicable for use with numerous commercial varieties. Rigorous selection and reducing the cytokinin level in medium immediately after shoot induction resulted in substantially greater frequency of adventitious shoots that developed defined stems suitable for rooting and reconstitution of transgenic plants. Transformation vectors were constructed for co-expression of genes encoding osmotin and tobacco chitinase Ia or PR-1b. Expression of osmotin, PR-1 and/or chitinase in transgenic carnation mediated a high level resistance of cv. White Sim (susceptible variety) to F. oxysporum f. sp. dianthi, race 2 in greenhouse assays. These plants are being evaluated in field tests. Comprehensive analysis (12 to 17 experiments) indicated that germination of B. cinerea conidia was unaffected by PR protein expression but germ tube elongation was reduced substantially. The disease severity was significantly attenuated by PR protein expression. Constitutive expression of osmotin in transgenic tomato increased resistance to B. cinerea, and P. infestans. Grey mold and late blight resistance was stable through the third selfed generation. The research accomplished in this project will have profound effects on the use of biotechnology to improve carnation and tomato. Transformation protocols that are applicable for efficient stable gene transfer to numerous commercial varieties of carnation and tomato are the foundation for the capacity to bioengineer these crops. The research further establishes that PR proteins provide a measure of enhanced disease resistance. However, considerations of PR protein combinations and conditional regulation and targeting are likely required to achieve; sustained level of resistance.