Brazil stands out in grain production, being the world's second-largest soya bean producer and the largest in Latin America. The area occupied by leguminous in the 2018/2019 harvest was 36 million hectares (CONAB, 2019). The Cerrado biome occupies about 44% of the country's agricultural area, which is responsible for 60% of total soya bean production (DICKIE, Magno, Giampietro, & Dolginow, 2016). The advance of agriculture in this biome is growing, which tends to further increase the percentage of crop production. In the Cerrado, the volume and frequency of rainfall is often fluctuating and insufficient, reducing the chances of adequate supply of the crop's water demand (Goes, Rodrigues, Arf, Arruda, & Vilela, 2011; Tardin et al., 2013). Therefore, it is common in Cerrado the soya bean crops to be subjected to drought stress conditions in their early stages, which can affect the germination process. The severity of the drought stress effect on soya bean depends on the

A metodologia de modelos mistos (REML/BLUP) tem sido empregada para estudar os efeitos da interação genótipo x ambiente (G x E) em várias culturas, como: arroz, feijão, cana-de-açúcar, cajueiro e eucalipto, porém ainda não foi aplicada em feijão-caupi. Assim, o objetivo deste trabalho foi selecionar simultaneamente genótipos de feijão-caupi semiprostrado cultivados no Estado do Mato Grosso do Sul, via modelos mistos, que reúnam alta adaptabilidade, estabilidade e produtividade de grãos. Foram conduzidos quatro ensaios de valor de cultivo e uso com genótipos de genótipos de feijão-caupi nos anos de 2005 e 2006 em Aquidauana, Chapadão do Sul e Dourados. O delineamento experimental utilizado foi o de blocos completos casualizados, com 20 genótipos e 4 repetições. Os parâmetros genéticos foram estimados pela metodologia REML/BLUP, e a seleção baseou-se no método da média harmônica do desempenho relativo dos valores genéticos (MHPRVG), em três estratégias: seleção com base no valor genético predito, tendo-se considerado o desempenho médio dos genótipos em todos os ambientes (sem efeito de interação) ou o desempenho em cada ambiente (com efeito da interação); e seleção simultânea quanto à produtividade de grãos, estabilidade e adaptabilidade. Os genótipos BRS Paraguaçu, MNC99-542F-5 e MNC99-508G-1 podem ser cultivados em vários ambientes, pois reúnem alta produtividade de grãos, adaptabilidade e estabilidade. A herdabilidade da média dos genótipos apresentou magnitude variando de moderada a alta, fato que indica excelentes possibilidades para a seleção, permitindo acurácia seletiva de 82%.Palavras-chave: BLUP/REML, parâmetros genéticos, Vigna unguiculata L. Genotype x environment interaction in semiprostrade cowpea genotypes via mixed models AbstractThe mixed model methodology (REML / BLUP) has been used to study the effects of genotype x environment interaction (G x E) in various crops, such as: rice, common bean, cane sugar, cashew and eucalyptus, but still was not applied in cowpea. The aim of this work was to select simultaneously semiprostrade cowpea genotypes grown in the state of Mato Grosso do Sul, via mixed models, bringing together high adaptability, stability and yield grain. It were conducted four growing amount of trials and use of genotypes of cowpea genotypes in 2005 and 2006 in Aquidauana, Chapadão do Sul and Dourados. The experimental design was a randomized complete blocks with four replications and 20 genotypes. The genetic parameters were estimated by REML/BLUP methodology and, the selection was based on the MHPRVG method (harmonic mean of the relative performance of genetic values) in three strategies: selection based on predicted breeding value, having considered the performance mean of genotypes in all environments (no interaction effect) or performance in each environment (with interaction effect); and simultaneous selection for grain yield, stability and adaptability. BRS Paraguaçu, MNC99-542F-5 and MNC99-508G-1 genotypes can be grown in various environments, as they bring together high grain ...

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ResumoObjetivou-se com este trabalho avaliar o desempenho agronômico e a divergência genética entre genótipos de feijão-caupi cultivados na região do ecótono Cerrado/Pantanal. O experimento foi conduzido no ano de 2008 na área experimental da Universidade Estadual de Mato Grosso do Sul, Unidade Universitária de Aquidauana (UEMS/UUA). Os tratamentos consistiram de 20 genótipos de feijão-caupi dispostos em delineamento de blocos casualizados com quatro repetições. Avaliaram-se os seguintes caracteres: início do florescimento, início de maturação, massa de cinco vagens, massa de grãos de cinco vagens, índice de grãos, massa de 100 grãos e produtividade de grãos. A divergência genética entre os tratamentos foi determinada com base na análise de agrupamento e nas variáveis canônicas. O genótipo BRS 17-Gurgueia apresentou maior produtividade de grãos. Híbridos com maior efeito heterótico serão obtidos do cruzamento entre a linhagem Pingo-de-ouro-2 com as cultivares BRS 17-Gurgueia e BRS-Paraguassu.Palavras-chave: caracteres agronômicos, dissimilaridade, variabilidade genética, Vigna unguiculata. Agronomic performance and genetic divergence among cowpea genotypes in Cerrado/ Pantanal ecotone AbstractThe objective of this study was to evaluate the agronomic performance and genetic divergence among genotypes of cowpea in the Cerrado/Pantanal ecotone region. The experiment was conducted in 2008 in the experimental area of the State University of Mato Grosso do Sul, University Unit of Aquidauana (UEMS/UUA). Treatments consisted of 20 genotypes of cowpea arranged in a randomized complete block design with four replications. Was evaluated the following characters: beginning of the flowering, beginning of the maturation, mass of five pods, grain mass of five pods, grain index, mass of 100 grains and grain yield. The genetic divergence between treatments was determined based on the clustering analysis and the canonical variables. The genotype BRS-17 Gurguéia showed higher grain yield. Hybrids with high heterotic effect will be obtained from crosses of Pingode-ouro-2 strain with BRS 17-Gurguéia and BRS-Paraguassu cultivars.

ABSTRACT. Seed cotton yield is a trait governed by multiple genes that cause changes in the performance of genotypes depending on the cultivation environment. Breeding programs examine the genotype x environment interaction (GE) using precise statistical methods, such as AMMI (additive main effects and multiplicative interaction) and GGE biplot (genotype main effects + genotype x environment interaction). The AMMI method combines the analysis of variance and principal components, to adjust the main effects (genotypes and environments) and the effects of GE interaction, respectively. The GGE biplot groups the genotype additive effect together with the multiplicative effect of the GE interaction, and submits both of these to the principal components analysis. The aim of this study was to investigate the association between the AMMI and GGE biplot methods and select cotton genotypes that simultaneously showed high productivity of seed cotton and stability in Mato Grosso environments. cotton productivity were analyzed by AMMI and GGE biplot methods. Both methods were concordant in the discrimination of environments and genotypes for phenotypic stability. The genotypes BRS ARAÇÁ and LD 05 CV had high seed cotton productivity and phenotypic stability, and could be grown in all environments across Mato Grosso State.

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Photosynthetic efficiency has become the target of several breeding programs since the positive correlation between photosynthetic rate and yield in soybean suggests that the improvement of photosynthetic efficiency may be a promising target for new yield gains. However, studies on combining ability of soybean genotypes for physiological traits are still scarce in the literature. The objective of this study was to estimate the combining ability of soybean genotypes based on F2 generation aiming to identify superior parents and segregating populations for physiological traits. Twenty-eight F2 populations resulting from partial diallel crossings between eleven lines were evaluated in two crop seasons for the physiological traits: photosynthesis, stomatal conductance, internal CO2 concentration, and transpiration. General combining ability (GCA) of the parents and specific combining ability (SCA) of the F2 populations were estimated. Our findings reveal the predominance of additive effects in controlling the traits. The genotype TMG 7062 IPRO is the most promising parent for programs aiming at photosynthetic efficiency. We have also identified other promising parents and proposed cross-breeding with higher potential for obtaining superior lines for photosynthetic efficiency.

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