Slow seed coat darkening is desirable in common bean cultivars and genetic parameters are important to define breeding strategies. The aims of this study were to estimate genetic parameters for plant architecture, grain yield, grain size, and seed-coat darkening in common bean; identify any genetic association among these traits; and select lines that associate desirable phenotypes for these traits. Three experiments were set up in the winter 2012 growing season, in Santo Antônio de Goiás and Brasília, Brazil, including 220 lines obtained from four segregating populations and five parents. A triple lattice 15 x 15 experimental design was used. The traits evaluated were plant architecture, grain yield, grain size, and seed-coat darkening. Analyses of variance were carried out and genetic parameters such as heritability, gain expected from selection, and correlations, were estimated. For selection of superior lines, a "weight-free and parameter-free" index was used. The estimates of genetic variance, heritability, and gain expected from selection were high, indicating good possibility for success in selection of the four traits. The genotype x environment interaction was proportionally more important for yield than for the other traits. There was no strong genetic correlation observed among the four traits, which indicates the possibility of selection of superior lines with many traits. Considering simultaneous selection, it was not possible to join high genetic gains for the four traits. Forty-four lines that combined high yield, more upright plant architecture, slow darkening grains, and commercial grade size were selected.

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Qualidade culinária e nutricional de linhagens de feijoeiro-comum tipo carioca e interação com ambientesOs objetivos deste trabalho foram estudar a variabilidade genética e a interação entre genótipos e ambientes para o tempo de cocção e o teor de proteína de grãos de feijão, bem como identificar linhagens elites de feijoeiro-comum de grãos carioca com baixo tempo de cocção, alto teor de proteína e alta adaptabilidade e estabilidade para esses dois caracteres. Foram realizados 16 experimentos em blocos ao acaso, com três repetições, conduzidos nas épocas de semeadura das águas, de seca e de inverno, nos estados de Goiás, Distrito Federal, Pernambuco, Sergipe, Bahia e Paraná, em 2009 e 2010. Os ensaios foram compostos por 16 linhagens elites de grão carioca e foram obtidos dados de tempo de cocção e de teor de proteína dos grãos. Os dados foram submetidos a análises de variância e de adaptabilidade e estabilidade, pela metodologia de Annicchiarico. Existe variabilidade genética tanto para tempo de cocção quanto para teor de proteína entre linhagens elites de feijão carioca; entretanto, para teor de proteína essa variabilidade é menor. O efeito ambiental é muito importante na expressão desses caracteres e é maior que o efeito genético. A interação entre genótipos e ambientes é importante para o tempo de cocção e para o teor de proteína de grãos de feijão. As linhagens CNFC 11951 e CNFC 11962 apresentam baixo tempo de cocção, alto teor de proteína e alta adaptabilidade e estabilidade para os dois caracteres. Palavras ABSTRACTThe objectives of this work were to study the genetic variability and the interaction between genotypes and environments for cooking time and protein content of bean grains as well as to identify elite lines of Carioca grain type with short cooking time, high protein content and high adaptability and stability for these two traits. Sixteen experiments were conducted in a complete randomized block design with three replications during the rainy, dry and winter seasons, in Goiás, Distrito Federal, Pernambuco, Sergipe, Bahia and Paraná States, in 2009 and 2010. Each trial was composed by 16 elite lines of Carioca grain type and the data of cooking time and protein content were obtained. Data were submitted to analysis of variance and to stability and adaptability analysis, according to the methodology proposed by Annichiarico. Genetic variability was found for cooking time and for protein content among Carioca common bean elite lines; however, for protein content this variability is lower. The environmental effect is important for the expression of these traits and is larger than the genetic effect. The interaction between genotypes and environments is important for cooking time and for protein content of common beans. The lines CNFC 11951 and CNFC 11962 presents short cooking time, high protein content and high stability and adaptability for both traits.

The objective of this work was to evaluate the interaction between genotypes and environments for grain yield of common bean (Phaseolus vulgaris) lines and cultivars with potential for use in family farming systems. Data from value for cultivation and use tests, carried out in 20 environments in the state of Goiás, Brazil, were analyzed in two cycles (2007/2008 and 2009/2010) in the dry, rainy, and winter crop seasons. Each test consisted of 15 genotypes from the carioca, purple, and rosinha common bean commercial groups. The experimental design was randomized complete block, with three replicates. The methodologies used to test the stability and adaptability of the genotypes were the one of Lin & Binns, of Cruz, the additive main effects and multiplicative interaction model (AMMI) to calculate the weighted average of absolute scores and productivity (WAASP), and the GGE biplot graphical analysis. The productive performance of the common bean lines and cultivars is affected by genotype x environment interaction. The methodologies adopted allow the selection of cultivars for cropping, and of cultivars and lines for use as parents in order to obtain segregating populations for selection in a family farming system.

Carioca is the most important edible dry bean (Phaseolus vulgaris L.) grown in Brazil. It represents the largest dry bean market class in the world. The seed coat of carioca beans will darken under adverse harvest conditions and with the increasing of storage time. In general, darkened seeds are associated with older seeds that suffer from prolonged cooking times. A relatively new ‘slow darkening’ trait is available in carioca that delays seed coat darkening under storage. However, its effect on cooking time is unknown. The objective of this work was to evaluate two induction methods of seed coat darkening and to examine the effect of slow darkening trait on cooking time after storage. Lines derived from four segregating populations resulting from crossings between cultivar BRSMG Madrepérola with slow seed coat darkening, and the parents BRS Estilo, BRS Cometa, BRS Notável and BRS Sublime with normal darkening were evaluated. An experiment inlcuding 220 lines, 55 per population and the five parents, in a 15x15 triple lattice was conducted in the winter growing season in Brasilia. Seed coat darkening and cooking time traits were evaluated. Two methods for inducing seed coat darkening were compared: an accelerated aging test using UV light for 72 hours, and an extended storage for 90 days under ambient conditions. The correlation between the induction methods ranged from 0.77 to 0.85 for the different populations indicating either method could be used to discriminate lines with normal versus slow darkening trait. The percentage of light-colored grain lines was identified by both induction methods of seed coat darkening ranged from 75 to 85.7% in the populations. The genetic correlation between seed coat darkening and cooking time varied from -0.06 to -0.48, indicating that in some populations there is no significant genetic correlation between seed coat darkening and cooking time. Thus, light colored grains are not indicative of low cooking time, when they are considered genotypes with genetic variation for the seed coat darkening.