In common bean (Phaseolus vulgaris L.) breeding, plant selection that associate erect plant architecture, high yield, and grains with good commercial acceptance has been the choice of breeders. Thus, this study aimed to evaluate potential parents, to obtain promising segregating populations that associate high yield, erect plant architecture and carioca grain type, as well as to obtain information on heterosis, general and specific combining ability of these parents regarding grain yield and traits related to plant architecture. Fourteen common bean lines were crossed under a partial diallel scheme. Group 1 was composed by eight erect plant lines and group 2 by six carioca grain type lines. The F 1 's plants from the crosses and the 14 parents were evaluated during spring (Mar. sowing) for plant architecture grade, diameter of the hipocotyl, plant mean height, and grain yield. Predominance of additive effects was observed for plant architecture grade and diameter of the hypocotyls. For grain yield and plant mean height, there was a greater contribution of the dominance effects. Thus, selection of erect plants, with a larger diameter of the hypocotyl can be carried out in early generations; while for grain yield and plant mean height, it must be delayed, preferably, to later generations.

The GGE Biplot method is efficien to identify favorable genotypes and ideal environments for evaluation. Therefore, the objective of this work was to evaluate the genotype by environment interaction (G×E) and select elite lines of cowpea from genotypes, which are part of the cultivation and use value tests of the Embrapa Meio-Norte Breeding Program, for regions of the Brazilian Cerrado, by the GGE-Biplot method. The grain yield of 40 cowpea genotypes, 30 lines and 10 cultivars, was evaluated during three years (2010, 2011 and 2012) in three locations: Balsas (BAL), São Raimundo das Mangabeiras (SRM) and Primavera do Leste (PRL). The data were subjected to analysis of variance, and adjusted means were obtained to perform the GGE-Biplot analysis. The graphic results showed variation in the performance of the genotypes in the locations evaluated over the years. The performance of the lines MNC02-675F-4-9 and MNC02-675F-4-10 were considered ideal, with maximum yield and good stability in the locations evaluated. There mega-environments were formed, encompassing environments correlated positively. The lines MNC02-675F-4-9, MNC02-675F-9-3 and MNC02-701F-2 had the best performance within each mega-environment. The environment PRL10 and lines near this environment, such as MNC02-677F-2, MNC02-677F-5 and the control cultivar (BRS-Marataoã) could be classified as those of greater reliability, determined basically by the genotypic effects, with reduced G×E. Most of the environments evaluated were ideal for evaluation of G×E, since the genotypes were well discriminated on them. Therefore, the selection of genotypes with adaptability and superior performance for specific environments through the GGE-Biplot analysis was possible.

-The objective of this study was to estimate the genetic gain of two recurrent selection cycles in common bean

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Palavras-chave: Phaseolus vulgaris, progresso genético, regressão linear. ABSTRACT RECURRENT SELECTION FOR THREE CHARACTERS IN COMMON BEANThe objective of this study was to estimate the genetic progress after three recurrent selection cycles in common bean. The progenies in each cycle were evaluated over three generations S 0:1 , S 0:2 and S 0:3 on the experimental field of the Department of Biology at the Federal University of Lavras (UFLA), in Lavras, Minas Gerais, from 2001 to 2006. In the experiments, grain yield, grain type and plant architecture were evaluated. Analyses of variance and the estimates of genetic and phenotypic parameters were obtained in all progeny evaluations. The progress per trait was estimated and, upon standardization of variables, the progress for the three traits simultaneously. Since the cycles refer to different years, the performance of two lines that participated in all evaluations was used as base to lessen the environmental effect in the estimates. The difference between the b's of the linear regression, of the number of cycles, the independent variable (x), and the mean performance of the trait under selection, the dependent variable (y), of the progenies and of the controls, provided the estimate of the genetic progress. Considering the three traits simultaneously after three recurrent selection cycles the genetic progress was 3.1% per cycle,. The existence of genetic variability in the progenies suggests the possibility of continuous success with selection.