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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Meloidogyne inornata em feijoeiro: aspectos biológicos e reação de cultivares / Meloidogyne inornata in bean: biological aspects and reaction cultivars

Dadazio, Tais Santo [UNESP] 23 February 2015 (has links) (PDF)
Made available in DSpace on 2015-08-20T17:09:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-23. Added 1 bitstream(s) on 2015-08-20T17:26:30Z : No. of bitstreams: 1 000843133.pdf: 967647 bytes, checksum: 323767d4bfb962e3f0d75dd14629569e (MD5) / A cultura do feijoeiro tem sua produtividade limitada por fatores bióticos, como os fitonematoides. Diversas espécies de têm sido relatadas causando danos à cultura, especialmente aquelas pertencentes ao gênero Meloidogyne. Recentemente, uma nova espécie foi relatada parasitando a cultura no Estado do Paraná, M. inornata. Em função desse relato, o presente trabalho teve como objetivo gerar informações acerca de seu ciclo biológico e sítio de alimentação, sob diferentes temperaturas, comparadas a M. incognita, caracterizar a reação de resistência de 32 cultivares de feijoeiro a M. inornata e verificar o potencial de danos desse nematoide. O teste de reação foi realizado em casa de vegetação, sendo inoculados 2.000 ovos/ planta. Após 50 dias, concluiu-se que todas as cultivares comportaram-se como suscetíveis frente ao nematoide, com FR variando de 13,69 a 94,71, para o grupo cores, e de 17,31 a 80,46, para o grupo preto. O experimento de nível de danos também foi realizado em casa de vegetação, inoculando-se as seguintes densidades populacionais de M. inornata em feijão cv. Tuiuiú: 0 (testemunha); 0,0625; 0,125; 0,25; 0,5; 1; 2; 4; 16; 32; e 64 ovos por cm3 de solo. O limite de tolerância estabelecido para a cultivar Tuiuiú inoculada com M. inornata foi de 9,9 nematoides cm3 de solo, ou seja, a partir dessa densidade populacional a planta passa a ser danificada pelo nematoide. Em relação à biologia comparativa de M. inornata com M. incognita, os experimentos foram realizados em câmara de crescimento do tipo BOD, nas temperaturas, de 18°C, 25°C e 32°C. Os resultados mostraram que temperatura de 25°C é a ideal para o desenvolvimento de ambas as espécies, enquanto aos 18°C, o ciclo de ambas as espécies é retardado e aos 32°C, o ciclo é acelerado; além disso, ambas as espécies formaram um sítio de alimentação permanente semelhante / The culture of the bean has its limited productivity by biotic factors, such as plant parasitic nematodes. Several species have been reported causing damage to the culture, especially those belonging to the genus Meloidogyne. Recently, a new species was reported parasite culture in State of Paraná, M. inornata. Due to this report, the present study aimed to generate information about its life cycle and feeding sites under different temperatures, compared to M. incognita, characterize the resistance reaction of 32 bean cultivars M. inornata and check the potential damage of this nematode. The reaction test was conducted in a greenhouse, and inoculated 2,000 eggs / plant. After 50 days, it was found that all cultivars susceptible behaved as against nematodes, with RF ranging from 13.69 to 94.71 for the color group and 17.31 to 80.46 for the group black. The damage level experiment was also carried out in a greenhouse, the inoculation of the following population densities of M. inornata in bean cv. Tuiuiú: 0 (control); 0.0625; 0.125; 0.25; 0.5; 1; 2; 4; 16; 32; and 64 eggs per cm3 of soil. The tolerance limit set for cultivating Tuiuiú inoculated with M. inornata was 9.9 cm3 of soil nematodes, that is, from that population density the plant becomes damaged by nematodes. Regarding the comparative biology of M. inornata with M. incognita, the experiments were conducted in a growth chamber type BOD at temperatures of 18 ° C, 25 ° C and 32 ° C. The results showed that at a temperature of 25 ° C is optimal for the development of both species, while at 18 ° C, the cycle of both species is retarded and 32 ° C, the cycle is accelerated; Furthermore, both species formed a similar permanent feeding site.
22

Meloidogyne inornata em feijoeiro : aspectos biológicos e reação de cultivares /

Dadazio, Tais Santo, 1989. January 2015 (has links)
Orientador: Silvia Renata Siciliano Wilcken / Coorientador: Andressa Zamboni Machado / Banca: Antonio Carlos Maringoni / Banca: Dhalton Shiguer Ito / Resumo: A cultura do feijoeiro tem sua produtividade limitada por fatores bióticos, como os fitonematoides. Diversas espécies de têm sido relatadas causando danos à cultura, especialmente aquelas pertencentes ao gênero Meloidogyne. Recentemente, uma nova espécie foi relatada parasitando a cultura no Estado do Paraná, M. inornata. Em função desse relato, o presente trabalho teve como objetivo gerar informações acerca de seu ciclo biológico e sítio de alimentação, sob diferentes temperaturas, comparadas a M. incognita, caracterizar a reação de resistência de 32 cultivares de feijoeiro a M. inornata e verificar o potencial de danos desse nematoide. O teste de reação foi realizado em casa de vegetação, sendo inoculados 2.000 ovos/ planta. Após 50 dias, concluiu-se que todas as cultivares comportaram-se como suscetíveis frente ao nematoide, com FR variando de 13,69 a 94,71, para o grupo cores, e de 17,31 a 80,46, para o grupo preto. O experimento de nível de danos também foi realizado em casa de vegetação, inoculando-se as seguintes densidades populacionais de M. inornata em feijão cv. Tuiuiú: 0 (testemunha); 0,0625; 0,125; 0,25; 0,5; 1; 2; 4; 16; 32; e 64 ovos por cm3 de solo. O limite de tolerância estabelecido para a cultivar Tuiuiú inoculada com M. inornata foi de 9,9 nematoides cm3 de solo, ou seja, a partir dessa densidade populacional a planta passa a ser danificada pelo nematoide. Em relação à biologia comparativa de M. inornata com M. incognita, os experimentos foram realizados em câmara de crescimento do tipo BOD, nas temperaturas, de 18°C, 25°C e 32°C. Os resultados mostraram que temperatura de 25°C é a ideal para o desenvolvimento de ambas as espécies, enquanto aos 18°C, o ciclo de ambas as espécies é retardado e aos 32°C, o ciclo é acelerado; além disso, ambas as espécies formaram um sítio de alimentação permanente semelhante / Abstract: The culture of the bean has its limited productivity by biotic factors, such as plant parasitic nematodes. Several species have been reported causing damage to the culture, especially those belonging to the genus Meloidogyne. Recently, a new species was reported parasite culture in State of Paraná, M. inornata. Due to this report, the present study aimed to generate information about its life cycle and feeding sites under different temperatures, compared to M. incognita, characterize the resistance reaction of 32 bean cultivars M. inornata and check the potential damage of this nematode. The reaction test was conducted in a greenhouse, and inoculated 2,000 eggs / plant. After 50 days, it was found that all cultivars susceptible behaved as against nematodes, with RF ranging from 13.69 to 94.71 for the color group and 17.31 to 80.46 for the group black. The damage level experiment was also carried out in a greenhouse, the inoculation of the following population densities of M. inornata in bean cv. Tuiuiú: 0 (control); 0.0625; 0.125; 0.25; 0.5; 1; 2; 4; 16; 32; and 64 eggs per cm3 of soil. The tolerance limit set for cultivating Tuiuiú inoculated with M. inornata was 9.9 cm3 of soil nematodes, that is, from that population density the plant becomes damaged by nematodes. Regarding the comparative biology of M. inornata with M. incognita, the experiments were conducted in a growth chamber type BOD at temperatures of 18 ° C, 25 ° C and 32 ° C. The results showed that at a temperature of 25 ° C is optimal for the development of both species, while at 18 ° C, the cycle of both species is retarded and 32 ° C, the cycle is accelerated; Furthermore, both species formed a similar permanent feeding site. / Mestre
23

Quantitative Field Testing Heterodera Glycines from Metagenomic Dna Samples Isolated Directly from Soil

Li, Yan 17 August 2013 (has links)
Molecular diagnostic assays have been developed and utilized to diagnose and to confirm the diagnoses of many plant-parasitic nematodes. We screened several gene sequences of soybean cyst nematode (SCN) [Heterodera glycines, Ichinohen] for their use as molecular markers. A methodology then was developed to use them to detect and quantify the number of H. glycines directly from Mississippi soil. A novel procedure utilizing multiple databases containing nematode DNA and EST sequences was developed to assist in the selection of SCN primers used in the PCR and qPCR assays. In vitro testing demonstrated that the DNA primers and probes developed from the novel procedure for the qPCR assays could accurately detect the presence of SCN. Subsequent testing resulted in a trend of increasing observed numbers of SCN contributing to increasing estimates by qPCR.
24

Functional Analysis Identifies Glycine Max Genes Involved in Defense to Heterodera Glycines

Matsye, Prachi D 17 August 2013 (has links)
The infection of plants by Heterodera glycines, commonly known as soybean cyst nematode (SCN), is a serious agricultural problem of worldwide extent. Meanwhile, it provides an excellent experimental model to study basic aspects of how cells function, in particular, during biotic challenge. Heterodera glycines challenges plant cells by initiating, developing and sustaining an interaction that results in the formation of a nurse cell from which the nematode derives nourishment. The presented experiments examine (1) how a cell can be de-differentiated and reprogrammed to perform a much different biological role and (2) how a cell’s immune responses can be engaged or suppressed to accomplish that goal. The observation of alpha soluble N-ethylmaleimide-sensitive factor attachment protein (alpha-SNAP) expression, its location within the rhg1 locus and known involvement in the vesicular transport machinery relating to defense made it a strong candidate for further functional analysis. Functional studies demonstrated that overexpression of alpha-SNAP in the susceptible G. max[Williams 82/PI 518671] genotype that lacks its expression results in the partial suppression of H. glycines infection. This indicated that the vesicles could be delivering cargo to the site of infection to engage a defense response. High levels of expression of a cell wall modifying gene called xyloglucan endotransglycosylase also occur during defense. XTHs associate with vesicles, act in the apoplast outside of the cell, and have a well-known function in cell wall restructuring. These observations indicated that alterations in the cell wall composition of nurse cells could be important for the successful defense response. Overexpression of a G. max xyloglucan endotransglycosylase (Gm-XTH) in the susceptible G. max[Williams 82/PI 518671] genotype resulted in a significant negative effect on H. glycines as well as R. reniformis parasitism. The results, including preliminary experiments on components of the vesicle transport system, identify a potent mechanism employed by plants to defend themselves from two types of plant-parasitic nematodes.
25

CHARACTERIZATION OF INDIANA HETERODERA GLYCINES VIRULENCE PHENOTYPES AND STUDY RESPONSE OF MELOIDOGYNE JAVANICA TO TOMATO ROOT EXUDATES

Ricky Joe Critchfield (15317902) 19 April 2023 (has links)
<p>  <em>Heterodera glycines</em> or soybean cyst nematode (SCN) is one of the most yield-limiting soybean plant pathogens. The HG (<em>Heterodera glycines</em>) type test is a greenhouse test to determine the virulence of SCN populations to seven soybean “indicator” lines. Since there has not been a survey of SCN virulence phenotypes in Indiana in over a decade, a total of 124 samples were collected, and all tested positive for SCN. Of 42 selected populations for the HG type test, 88% were virulent to the soybean breeding line PI 88788, from which most SCN-resistant cultivars derive their resistance. All populations were virulent to at least one indicator line, including PI 548402 (‘Peking’), which pose problems for the future of soybean breeding for SCN. <em>Meloidogyne</em> spp. or root-knot nematodes (RKNs) are extremely damaging to agriculture, especially to specialty crops. RKN species are attracted by plant root exudates. The gene expression of <em>M. javanica</em> second-stage juveniles was determined after exposure to tomato root exudates, and the differentially expressed genes were analyzed.</p>
26

Interactions of Purple Deadnettle, Lamium purpureum, Soybean Cyst Nematode, Heterodera glycines and Italian Ryegrass, Lolium multIflorum

Ackley, Bruce A. January 2013 (has links)
No description available.
27

Investigating Root-Knot and Soybean Cyst Nematode Parasitic Interactions through Transcriptomic Analyses of the Host and Parasite

Walsh, Ellie Kathleen January 2016 (has links)
No description available.
28

Evaluation of <i>Heterodera glycines</i> - <i>Macrophomina phaseolina</i> Interactions on Soybean

Lopez Nicora, Horacio Daniel 31 October 2016 (has links)
No description available.
29

Estudo genético de populações de soja com fonte de resistência à Heterodera glycines (raça 3) oriundas de topocruzamentos do tipo alimento x tipo grão /

Teixeira, Lilian Cristina Andrade de Araújo. January 2016 (has links)
Orientador: Sandra Helena Unêda-Trevisoli / Coorientador: Ana Cristina Pinto Juhász / Coorientador: Luciany Favoreto / Banca: João Antônio da Costa Andrade / Banca: Ivana Marino Barbaro / Banca: Jaime Maia dos Santos / Banca: Pedro luiz Martins Soares / Resumo: A soja [Glycine max (L.) Merrill] é uma leguminosa de ciclo anual que apresenta distintas finalidades, dentre elas, uma crescente vertente relaciona-se ao uso na alimentação humana. Há demanda de cultivares de soja com esta destinação com resistência a patógenos e pragas. Em especial destaca-se o nematoide de cisto da soja (Heterodera glycines) que causa expressiva perda na produtividade. Em virtude do exposto, utilizando topocruzamentos de soja tipo alimento x tipo grão, o objetivo do presente trabalho é: a. Determinar a herança da cor do tegumento, da cor do hilo e da expressão do caráter derramamento de hilo em populações F2:3; b. Determinação do estudo da herança da resistência ao nematoide de cisto da soja (NCS), bem como estimativa do número e modo de ação dos genes envolvidos a fim de contribuir no delineamento de cruzamentos, que envolvem os genitores em estudo, com maior possibilidade de acumular genes que conferem resistência à raça 3 do NCS e; c. Verificar com uma abordagem quantitativa, a adequação das populações a um modelo aditivo-dominante, assim como estimar parâmetros genéticos nos cruzamentos gerados. Utilizaram-se genitores contrastantes, um resistente ao NCS raça 3 ('BRSMG 810C') e dois suscetíveis, porém aptos para utilização na alimentação humana ('BRSMG 790A' e 'BRSMG 800A'). Obtiveram-se as gerações F1, RCr, RCs e F2 que foram utilizadas para o estudo da herança da resistência, por meio da segregação do caráter. As avaliações de nematoide foram realizadas utilizando-se como estimador o Índice de Fêmeas (IF) e analisadas pelo teste de Qui-Quadrado (χ2) para testar o ajuste ao modelo proposto para a herança. As sementes F3 provenientes de plantas F2 foram caracterizadas para elucidar a herança para caracteres morfológicos de interesse (cor de tegumento, cor e aspecto de hilo). Para os caracteres morfológicos dos... / Abstract: Soybean [Glycine max (L.) Merrill] is an annual leguminous that has distinct purposes, among them, a growing amount is related to the human feed. There is a demand of cultivars aiming this destination, which are resistant to pathogens and plagues. A special plague is highlighted, the soybean nematode of cyst (Heterodera glycines) (NCS). It causes expressive loss of productivity. Facing this, using soybean topcrosses feed-like x grain-like this work aims: a. determine the tegument color, hilum color, and hilum spread character heritance in F2 populations; b. determine the NCS resistance heritage, as well the involved genes number and action mode estimative in order to contribute in the crosses design, which involve the parents studied, with a higher possibility of accumulation of genes which provide resistance to the NCS race 3; and c. Verify in a quantitative approach the adequacy population in an additive-dominant model, as well estimate the genetic parameter into the crossings. We used contrasting parents, being resistant to the race 3 ('BRSMG 810C') and two susceptible, however suitable to the human feed ('BRSMG 790A' and 'BRSMG 800A'). Thus, the generations F1, RCr, RCs, and F2 were created. They were used to study heritage resistance through the character segregation. The nematode evaluations were done using as estimator the Female Index (IF) and they were analyzed by the chi-square test (χ2) to test the adjustment to the suggested model to the heritage. The F3 seeds from the F2 plants were characterized to elucidate the heritage to interest morphologic traits (seed coat color, hilum color and hilum aspect). For the morphological character of grain, the results observed of descendent were adjusted to the expected proportion, considering that there were four genes (R/I/W/T) controlling the expression coat and hilum color to both crossings. At crossing ... / Doutor
30

Functional Genomic Studies of Soybean Defenses against Pests and Soybean Meal Improvement

Lin, Jingyu (Lynn) 01 December 2011 (has links)
Soybean [Glycine max (L.) Merr.] is an important crop worldwide. It has been widely consumed for protein, oil and other soy products. To develop soybean cultivars with greater resistance against pests and improved meal quality, it is important to elucidate the molecular bases of these traits. This dissertation aims to investigate the biochemical and biological functions of soybean genes from four gene families, which are hypothesized to be associated with soybean defense against pests and soybean meal quality. There are three specific objectives in this dissertation. The first one is to determine the function of components in the salicylic acid (SA) signaling pathway in soybean resistance against soybean cyst nematode (Heterodera glycines, SCN). The second one is to determine whether insect herbivory induce the emission of volatiles from soybean, and if so, how these volatiles are biosynthesized. The third objective is to identify and characterize soybean mannanase genes that can be used for the improvement of soybean meal quality. The soybean genome has been fully sequenced, which provides opportunities for cross-species comparison of gene families of interest and identification of candidate genes in soybean. The cloned cDNAs of putative genes were expressed in Escherichia coli to produce recombinant enzymes. Through biochemical assays, these proteins were proved to be soybean salicylic acid methyltransferase (GmSAMT1), methyl salicylate esterase (GmSABP2-1), α[alpha]-farnesene synthase (GmTPS1) and E-β[beta]-caryophyllene synthase (GmTPS2), and endo-β[beta]-mannanase (GmMAN1). Through a transgenic hairy root system harboring overexpression of GmSAMT1 and GmSABP2-1, both of these two genes were evaluated for their biological function related to resistance against SCN. The results showed that the over-expression of GmSAMT1 and GmSABP2-1 in the susceptible soybean background lead to enhanced resistance against SCN. Among four putative soybean mannanase genes, one gene was cloned and characterized. GmMAN1 showed the endo-β[beta]-mannanase hydrolyse activity and can hydrolyze cell walls isolated from soybean seeds. In summary, using comparative and functional genomics, a number of genes involved in soybean defense and meal quality were isolated and characterized. This study provides novel knowledge and molecular tools for the genetic improvement of soybean for enhanced resistance and improved meal quality.

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