MSCAGR ( Plant Production) / Department of Plant Production / See the attached abstract below

Orientador: Edson Luiz Lopes Baldin / Resumo: A soja, [Glycine max (L.) (Merrill)] é um dos principais grãos produzidos mundialmente, com o Brasil apresentando grande destaque em produtividade e exportação. Diversos fatores podem comprometer a produção desta leguminosa, no qual o ataque de insetos fitófagos possui grande relevância. Dentre os insetos-praga para a cultura da soja, Euschistus heros (Fabricius) possui grande importância pela alta incidência no campo e elevado danos ocasionados. Como alternativa à baixa eficiência dos métodos de controle e aplicações indevidas de defensivos químicos, este trabalho procurou avaliar a tolerância de quatro genótipos de soja frente ao ataque de E. heros (3 percevejos/planta) em diferentes fases fenológicas (R3, R5, R7, R3 até o final do ciclo e controle) a campo em duas safras, e respostas enzimáticas, analisadas em laboratório, após o ataque de E. heros em casa de vegetação durante a fase fenológica R5 por diferentes períodos de infestação (7, 14, 21 dias). Para isto, foi avaliado a campo a produtividade, peso de 100 grãos, número de vagens/ 10 plantas, número de grãos/10 plantas, retenção foliar e nível de danos ocasionados. Em casa de vegetação avaliou-se produtividade da linha central, número de vagens e número de grãos. Posteriormente, em análises químicas realizadas em laboratório, foram avaliadas as atividades das enzimas peroxidase, polifenol oxidase, catalase, superóxido dismutase e proteínas totais solúveis. Os genótipos ‘Conquista’ infestado em R3, ‘IAC 100’ infestado... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

Orientador: Rafael Montanari / Resumo: Os estudos dos atributos físicos do solo, componentes de produção e produtividade das culturas em conjunto com a geoestatística, e com a geração de mapas de krigagem, resultam na racionalização dos recursos e insumos nas tomadas de decisões para um manejo mais adequado. Objetivou-se com este trabalho avaliar o efeito da escarificação do solo nos atributos físicos e a sua implicação na produtividade da soja em um Latossolo Vermelho distrófico e analisar os principais atributos físicos do solo que melhor se relacionam com a produtividade, visando implementar um manejo adequado e proporcionar zonas específicas de manejo. O experimento foi no ano agrícola 2015/16, na Fazenda de Ensino, Pesquisa e Extensão da Faculdade de Engenharia - UNESP, Câmpus de Ilha Solteira/SP e consistiu em duas áreas de cultivo, uma sob sistema plantio direto (SPD) e outra sob cultivo mínimo (CM). Para a coleta dos dados, foram alocadas duas malhas geoestatísticas, uma em cada área de plantio. Cada malha foi constituída de 51 pontos equidistantes com uma distância entre pontos de 10 m. Avaliaram-se a população de plantas (POP), o número de vagens por planta (NVP), o número de grãos por planta (NGP), o número de grãos por vagem (NGV), a massa de 100 grãos (MCG), a produtividade de grãos (PRG), bem como os atributos físicos do solo como macroporosidade (MA), microporosidade (MI), porosidade total (PT), densidade do solo (DS), densidade da partícula (DP), teor de argila (Arg), areia (Are), silte (Sil), umid... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21377号 / 農博第2301号 / 新制||農||1069(附属図書館) / 学位論文||H30||N5150(農学部図書室) / 京都大学大学院農学研究科農学専攻 / (主査)教授 奥本 裕, 教授 白岩 立彦, 教授 稲村 達也 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Soybean (Glycine max) yield is significantly affected by soybean cyst nematode (SCN), Heterodera glycines, and causes an annual loss of billions of US dollars. In this study, Glycine max xyloglucan endotransglycosylase/hydrolase gene (Gm-XTH52) was transformed into a nematode susceptible G. max [Williams 82/PI 518671] variety of soybean to test whether the protein expression has a role in resistance to H. glycines, and possible chemical changes the expression may cause in the plant composition. Expression level of the Gm-XTH52 gene was three times higher than in controls. Significant reduction in the number of SCN cysts suggested suppression of H. glycines parasitism upon transformation. While total sugar amounts did not significantly differ between the transformed and control plants, xyloglucan amounts of loosely bound sugars of genetically mosaic plants were significantly lower in comparison to controls. Control plants showed lower molecular weight sugars than the transformed plants not subjected to H. glycines infection.

No description available.

Research was conducted in 2014 to evaluate the efficacy of harvest-aid systems and the performance of harvest aids applied at various timings in Mid-South soybean production. Evaluations included yield, desiccation, green stems and pods, and seed quality. Saflufenacil did not perform as well as the producer standard 14 DAT at the Starkville, MS location with desiccation levels of 78 and 98%, respectively. However, similar performance was observed 14 DAT at the Brooksville, MS location. When applied at R6.5, paraquat based treatments improved desiccation and reduced green stem 7 DAT compared to other treatments. No yield differences were observed between harvest aid treatments. However, yield differences were observed between the R6.0 and R6.5 timings. These data suggest saflufenacil is an effective harvest aid option, but may require up to 14 days for optimum desiccation. In addition, yield is not impacted by harvest aid product, but rather the timing of the application.

No description available.

Soybean mosaic virus (SMV) and peanut mottle virus (PMV) are potyviruses that can cause serious yield reductions in soybean [Glycine max (L.) Merr.]. Virus resistant soybean cultivars have been released with alleles at the Rsv1 and Rpv1 locus that confer resistance to SMV and PMV, respectively. A high-resolution map-based cloning approach was undertaken to isolate Rsv1 and Rpv1 from soybean, with hopes of providing insight into this host-pathogen relationship. A mapping population of 1,056 F2 individuals was constructed from the cross of the resistant cultivar PI 96983 (Rsv1 and Rpv1) by the susceptible cultivar Lee 68 (rsv1 and rpv1). Ninety-one of the 1,056 F2 individuals had a cross-over (recombination) in the chromosomal region between microsatellite, or simple sequence repeat (SSR) marker loci Hsp176 and Sat120, and these 91 recombinant lines (RLs) were selected for further genetic analysis. Genotypes of Rsv1 and Rpv1 for the 91 RLs were obtained by inoculating their F2:3 progeny with SMV-G1 and PMV-P1, respectively. The 91 RLs also were used for mapping one random amplified polymorphic DNA (RAPD), five SSR, and 21 restriction fragment length polymorphism (RFLP) markers. Included in these RFLP markers were seven resistance gene candidate (RGC) and five resistance gene candidate flanking (RGCF) markers. RGC probes encode a protein with homology to previously cloned plant disease resistance genes, and RGCF probes are sequences obtained from the flanking regions of candidate disease resistance genes. The resultant high-resolution map consisted of 41 marker loci detected by 27 molecular markers. Rsv1 and Rpv1 cosegregated with one or more RFLP bands detected by RGCF probes: GG27-1a, 3gG2SP, and/or T3G. Analyses of the disease reaction and molecular marker data from seven RLs suggested that the map position of Rsv1 should be at a locus different from that designated by the linkage analysis software, Mapmaker 3.0. Compared to the other 89 RLs, a high percentage (>34%) of F3 plants grown from four of these seven RLs gave a necrotic reaction when inoculated with SMV-G1. From this evidence, we believed that another locus independent of Rsv1 was involved in PI 96983's response to SMV-G1. The two loci conferring resistance to SMV-G1 were designated Rsv1a and Rsv1b. / Master of Science

Disease outbreaks caused by oomycetes can be catastrophic. The first part of this dissertation describes development of a system to identify potential new and durable resistance (R) genes against P. sojae in soybean germplasm. We developed a system to screen soybean germplasm for genes that recognize core Phytophthora sojae RXLR effectors that are conserved within the pathogen species and essential for virulence. R genes that recognize these effectors will likely be effective and durable against diverse P. sojae isolates. We developed a system to deliver individual P. sojae effectors by Type III secretion into soybean using the bacterium Pseudomonas, and we screened 12 core effectors on a collection of 30 G. max lines that likely contain new resistance genes against P. sojae. We identified candidate R genes against 10 effectors. Genetic segregation ratios from crosses indicated that three of these genes have a simple inheritance pattern and would be amenable to breeding into elite cultivars. The second part of the dissertation involves use of a model plant-oomycete system to study the genetic basis of susceptibility to oomycete diseases. We compared host transcriptomes from a resistant and a susceptible infection of Arabidopsis thaliana by the downy mildew pathogen Hyaloperonospora arabidopsidis (Hpa). We identified five gene clusters with expression patterns specific to the susceptible interaction. Genes from each cluster were selected and null mutants were tested for altered susceptibility to virulent Hpa. Most A. thaliana null mutants showed enhanced disease susceptibility, suggesting their involvement in pattern-triggered immunity (PTI). A knockout mutant in the AtGcn5 gene was completely resistant to Hpa Emco5 suggesting that the gene/protein is necessary for Hpa to successfully colonize the plant. This study provided new molecular insights into plant-oomycete interaction and revealed a plant gene that could potentially be engineered to provide enhanced resistance to oomycete pathogens. / Ph. D.