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

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Glifosato e manganês na cultura da soja transgênica: fisiologia e nutrição de planta, características agronômicas e análise econômica

Pós-graduação em Agronomia - FEIS

Diagnose foliar da cultura da soja em função da aplicação superficial de lodos de esgoto e resíduos industriais sob diferentes doses em sistema plantio direto

The application of industrial and municipal waste in the soil may be recommended by your corrective and fertilizer value, giving the great potential for agricultural reuse, improves physical, chemical and biological soil properties and helps to reduce the consumption of fertilizers and correctives, without contamination by heavy metals. This study aimed to evaluate the absorption of nutrients and potentially toxic elements, and their effect on the development of soybean (Glycine max (L.) Merrill) grown under No-Tillage system (NT). The work was developed in the field, at the Experimental Farm Lageado - FCA / UNESP, Botucatu (SP) in an Oxisol under tropical climate of altitude. The experimental design was randomized blocks, factorial 4x4+1, with four replications. The treatments consisted of four residues: two sewage sludge, one centrifuged and treated with quicklime (LC) and a biodigester (LB) and two industrial wastes: steel slag (E) and lime mud (Lcal) , applied in dosages of 0, 2, 4 and 8 Mg ha-1. The surface application of LC, LB, Lcal and E residues in soil under NT favored the development of soybean, with no heavy metal contamination, given the current legislation.

Doses de Bradyrhizobium japonicum e Azospirillum brasilense no desenvolvimento das plantas, na produção e na qualidade fisiológica de sementes de soja

Pós-graduação em Agronomia - FEIS

Maize and soybeans production in integrated system under no-tillage with different pasture combinations and animal categories

The adoption of no-till system (NTS) combined with crop-livestock integration (CLI) has been a strategy promoted in Brazil, aiming to maximize areas yield and increase agribusiness profitability. This study aimed to evaluate grains yield and phytotechnical attributes from maize and soybean culture by CLI system under NTS after winter annual pure and diversified pastures with the absence or presence of grazing animals. The experiment was installed in Castro (Parana State, Brazil) on in a dystrophic Humic Rhodic Hapludox with a clay texture, using experimental design of randomized complete blocks in 4 x 2 factorial scheme with three replications. Treatments included four pasture combinations (diversified or pure) and animal categories (light and heavy) subjected or not to grazing animals during the winter. During 2008/09 and 2009/10 summers, the area was cultivated with soybeans and maize, respectively, with yield assessment of grains and phytotechnical attributes. Treatments did not alter the yield and weight of a thousand seeds (WTS) of soybeans. In maize culture, the grazing animal during the winter increased the plant population and grains yield, but gave slight decrease in WTS. Pasture combinations (diversified or pure) and animal categories (light and heavy) did not interfere in soybean culture, but benefited the maize crop.

Institutional arrangements in the emerging biodiesel industry: Case studies from Minas Gerais-Brazil

Connecting (small) family farmers to the emerging biodiesel industry requires careful design of the institutional arrangements between the producers of oil crops and the processing companies. According to institutional economics theory, the design of effective and efficient arrangements depends on production and transaction characteristics, the institutional environment, and the organizational environment supporting the transaction between producers and the industry. This paper presents a comparative study on two cases in the feedstock-for-biodiesel industry in the state of Minas Gerais, Brazil. The two case studies represent the production and transaction system of soybeans (Glycine max L Merrill) and castor beans (Ricinus communis L). Important elements of effective and efficient institutional arrangements are farmer collective action, availability of technical and financial support, and farmer experience with particular crops. (C) 2011 Elsevier Ltd. All rights reserved.

ASSESSING Bemisia tabaci (GENN.) BIOTYPE B RESISTANCE IN SOYBEAN GENOTYPES: ANTIXENOSIS AND ANTIBIOSIS

Since it was first reported in Brazil in the 1990s, the B biotype of silverleaf whitefly (Bemisia tabaci [Genn.], Hemiptera: Aleyrodidae) has been recognized as an important pest in soybeans (Glycine max L.), reducing the productivity of this legume species in some areas of the country. As an alternative to chemical control, the use of resistant genotypes represents an important tool for integrated pest management (IPM). This study evaluated the performance of 10 soybean genotypes prior to whitefly infestation, by testing attractiveness and preference for oviposition in the greenhouse and antibiosis in the laboratory. In a multiple-choice test, 'IAC-17' was the least attractive to insects. In a no-choice test, 'IAC-17' was the least attractive for, egg deposition, indicating the occurrence of non-preference for oviposition on this genotype. Trichome density was positively correlated with the oviposition site and may be associated with the resistance of 'IAC-17' to infestation. The genotypes 'IAC-PL1', 'IAC-19', 'Conquista', 'IAC-24' and 'IAC-17' extended the insect's life cycle, indicating the occurrence of a small degree of antibiosis and/or non-preference for feeding.

Adubação mineral com cobalto e molibdênio na cultura da soja

Altas produtividades de soja requerem grandes quantidades de nitrogênio, que podem ser obtidas principalmente, a partir da fixação simbiótica. No entanto, há possibilidade da eficiência desse processo biológico ser prejudicada pela deficiência de micronutrientes, especialmente de cobalto e molibdênio. Nesse contexto, objetivou-se com o presente trabalho avaliar a eficiência agronômica e a forma de aplicação de adubação mineral com cobalto e molibdênio na cultura da soja. Para tanto, a cultivar CD-206 foi submetida a diferentes tratamentos que consistiram da combinação entre aplicação de Co e Mo via tratamento de sementes e adubação foliar. As características agronômicas avaliadas foram o número de nódulos, massa seca da parte aérea, massa seca de raiz, número de vagens, número de grãos, massa de mil grãos e produção de grãos. A aplicação de molibdênio e cobalto via sementes e/ ou adubação foliar no estádio V4 (terceira folha trifoliolada completamente desenvolvida, quarto nó) promoveram incrementos significativos no rendimento da cultura. Respostas positivas ao cobalto e molibdênio também foram observadas no número de nódulos, vagens e grãos, com aumentos de até 240 kg ha-1 no rendimento da cultura. Os parâmetros agronômicos avaliados foram afetados positivamente pela aplicação de Co e Mo, principalmente quanto aplicado tanto via semente como foliar (TS + V4), inclusive para a produtividade de grãos. A forma de aplicação não foi significativamente distinta, ou seja, tanto a aplicação via semente como via foliar foram eficientes no fornecimento destes nutrientes para a cultura da soja.

Análise de imagens na avaliação de danos mecânicos em sementes de soja

A injúria mecânica é um dos mais importantes fatores na redução da qualidade de sementes de soja. Neste contexto, este trabalho objetivou avaliar a influência da pressão de impacto e o teor de água em sementes, bem como a aplicabilidade da técnica de análise de imagens, na ocorrência de danos mecânicos em sementes de soja. Sementes das cultivares Vencedora e Monsoy 8001, com teores de água de 13% e 18%, foram submetidas a danos mecânicos, com a utilização de equipamento simulador de impactos (551,6 KPa e 965,3 KPa). Posteriormente, as sementes foram secas a 32ºC, até atingirem 12% de teor de água. Imediatamente após os impactos e após cinco meses de armazenamento, as sementes foram avaliadas pelos testes de tetrazólio e raios X. A pressão de impacto e o teor de água nas sementes exerceram efeitos diretos na severidade do dano mecânico, porém, o local do impacto exerceu maior influência do que aqueles fatores. A técnica de análise de imagens foi de grande utilidade na avaliação de danos mecânicos em sementes de soja, possibilitando a análise detalhada dos efeitos de diferentes fatores.

Soybean Aphid Efficacy Evaluation

Soybean, Glycine max (L.), grown in Iowa and most of the north central region of the United States, has not required regular insecticide usage. The soybean aphid, Aphis glycines (Hemiptera: Aphididae), causes yield losses from direct plant feeding, and has been shown to transmit several plant viruses. In Iowa, soybean aphid can colonize soybean fields in June and has developed into outbreaks in July and August capable of reducing yields by nearly 40 percent.

Distancias genéticas entre perfiles moleculares obtenidos desde marcadores multilocus multialélicos

Para expresar la magnitud de la identidad genética (similaridad) o su complemento (distancia) entre dos individuos caracterizados molecularmente a través de marcadores del tipo microsatélites (SSR), que son multilocusmultialélicos, es necesario elegir una métrica acorde con la naturaleza multivariada de los datos. Comúnmente, las métricas de distancias genéticas son diseñadas para expresar, en un único número, la diferencia genética entre dos poblaciones y son expresadas como función de la frecuencia alélica poblacional. Dichas métricas pueden también ser utilizadas para calcular la distancia entre perfiles individuales, pero las frecuencias alélicas no son continuas en este caso. Alternativamente, se pueden usar distancias geométricas obtenidas como el complemento del índice de similaridad para datos binarios que indican la presencia/ ausencia de cada alelo en un individuo. El objetivo de este trabajo fue evaluar simultáneamente el desempeño de ambos tipos de métricas para ordenar y clasificar individuos en una base de datos generadas a partir de loci de marcadores microsatélites SSR. Se calcularon 11 métricas de distancias a partir de 17 loci SSR obtenidos desde 17 introducciones de un banco de germoplasma de soja [Glycine max (L.) Merr.]. Se evaluó el consenso de los resultados obtenidos para la clasificación de los 17 perfiles moleculares desde varias métricas. Los resultados sugieren que los diferentes tipos de métricas producen información similar para comparar individuos. No obstante, se realizó una clasificación de las métricas que responden a diferencias entre los núcleos de las expresiones de cálculo.

Absorption and mobility of foliar-applied boron in soybean as affected by plant boron status and application as a polyol complex

In the present study (i) the impact of plant Boron (B) status on foliar B absorption and (ii) the effect of B complexation with polyols (sorbitol or mannitol) on B absorption and translocation was investigated. Soybean (Glycine max (L.) Meer.) plants grown in nutrient solution containing 0 μM, 10 μM, 30 μM or 100 μM 11B labelled boric acid (BA) were treated with 50 mM 10B labelled BA applied to the basal parts of two leaflets of one leaf, either pure or in combination with 500 mM sorbitol or mannitol. After one week, 10B concentrations in different plant parts were determined. In B deficient leaves (0 μM 11B), 10B absorption was significantly lower than in all other treatments (9.7% of the applied dose vs. 26%–32%). The application of BA in combination with polyols increased absorption by 18–25% as compared to pure BA. The absolute amount of applied 10B moving out of the application zone was lowest in plants with 0 μM 11B supply (1.1% of the applied dose) and highest in those grown in 100 μM 11B (2.8%). The presence of sorbitol significantly decreased the share of mobile 10B in relation to the amount absorbed. The results suggest that 11B deficiency reduces the permeability of the leaf surface for BA. The addition of polyols may increase 10B absorption, but did not improve 10B distribution within the plant, which was even hindered when applied a sorbitol complex.

Tratamiento magnético como técnica estimulante de la germinación de semillas de soja

El campo magnético está presente en la naturaleza y afecta al reino vegetal y animal. El bioelectromagnetismo es el estudio de los efectos de los campos electromagnéticos sobre los sistemas biológicos y sus interacciones con los campos magnéticos naturales y artificiales. Estudios previos han determinado que la aplicación de campos magnéticos modifica la velocidad de germinación y el desarrollo de plantas. La soja constituye uno de los cultivos oleaginosos más importantes del mundo: en las últimas décadas su popularidad se ha incrementado por considerar esta leguminosa como una fuente de salud. Este estudio se centra en el efecto que se puede producir en la germinación de la soja (Glycine max L.) al exponerlo a campos magnéticos estacionarios de 125 mT, 250 mT y 300 mT durante diferentes tiempos de exposición (10¿,20¿, 1 hora, 24 horas y de forma permanente). Se observan diferencias muy significativas tanto en la velocidad de germinación como en el porcentaje de semillas germinadas entre las semillas control y las tratadas. Estos resultados ofrecen nuevas posibilidades para una más efectiva producción vegetal.

Isolation of Ethylene-Insensitive Soybean Mutants That Are Altered in Pathogen Susceptibility and Gene-for-Gene Disease Resistance1

Plants commonly respond to pathogen infection by increasing ethylene production, but it is not clear if this ethylene does more to promote disease susceptibility or disease resistance. Ethylene production and/or responsiveness can be altered by genetic manipulation. The present study used mutagenesis to identify soybean (Glycine max L. Merr.) lines with reduced sensitivity to ethylene. Two new genetic loci were identified, Etr1 and Etr2. Mutants were compared with isogenic wild-type parents for their response to different soybean pathogens. Plant lines with reduced ethylene sensitivity developed similar or less-severe disease symptoms in response to virulent Pseudomonas syringae pv glycinea and Phytophthora sojae, but some of the mutants developed similar or more-severe symptoms in response to Septoria glycines and Rhizoctonia solani. Gene-for-gene resistance against P. syringae expressing avrRpt2 remained effective, but Rps1-k-mediated resistance against P. sojae races 4 and 7 was disrupted in the strong ethylene-insensitive etr1-1 mutant. Rps1-k-mediated resistance against P. sojae race 1 remained effective, suggesting that the Rps1-k locus may encode more than one gene for disease resistance. Overall, our results suggest that reduced ethylene sensitivity can be beneficial against some pathogens but deleterious to resistance against other pathogens.

Purification of the Trehalase GMTRE1 from Soybean Nodules and Cloning of Its cDNA. GMTRE1 Is Expressed at a Low Level in Multiple Tissues1

Trehalose (α-d-glucopyranosyl-1,1-α-d-glucopyranoside), a disaccharide widespread among microbes and lower invertebrates, is generally believed to be nonexistent in higher plants. However, the recent discovery of Arabidopsis genes whose products are involved in trehalose synthesis has renewed interest in the possibility of a function of trehalose in higher plants. We previously showed that trehalase, the enzyme that degrades trehalose, is present in nodules of soybean (Glycine max [L.] Merr.), and we characterized the enzyme as an apoplastic glycoprotein. Here we describe the purification of this trehalase to homogeneity and the cloning of a full-length cDNA encoding this enzyme, named GMTRE1 (G. max trehalase 1). The amino acid sequence derived from the open reading frame of GMTRE1 shows strong homology to known trehalases from bacteria, fungi, and animals. GMTRE1 is a single-copy gene and is expressed at a low but constant level in many tissues.