Abstract The objective of this work was to evaluate common bean lines for yield and commercial grain quality in multi-environments, and to maximize the efficiency of selection using complementary methods. Over three crop years, 79 trials using carioca common bean lines were carried out in the dry, winter, and rainy crop seasons, in the Southern, Southeastern, Midwestern, and Northeastern regions of Brazil. The experimental design was a randomized complete block with three replicates and 17 genotypes. The evaluated traits were: grain yield (GY), grain appearance (GA), sieve yield (SY), and 100-seed weight (100SW). Adaptability and stability analyses were carried out using models that consider the genotype effect as fixed or as random, in a mixed-model perspective. A significant interaction between genotypes and environments was observed for all traits evaluated. The CNFC 15086 line presented the highest GY and 100SW, besides a high adaptability and stability. The most prominent line for GA was CNFC 15038. The CNFC 15097 line is recommended as a cultivar (BRS FC406) because it shows, simultaneously, favorable performances for GY, GA, SY, and 100SW, as well as for adaptability and stability.

Resumo O objetivo deste trabalho foi avaliar linhagens de feijão-comum quanto à produtividade e à qualidade comercial de grãos em multiambientes, e maximizar a eficiência da seleção por meio de métodos complementares. Ao longo de três anos agrícolas, 79 ensaios com linhagens de feijão-comum do tipo carioca foram conduzidos nas safras da seca, do inverno e do verão, nas regiões Sul, Sudeste, Centro-Oeste e Nordeste do Brasil. O delineamento experimental foi em blocos ao acaso, com três repetições e 17 genótipos. Os caracteres avaliados foram: produtividade de grãos (GY), aparência de grãos (GA), rendimento de peneira (SY) e massa de 100 grãos (100SW). As análises de adaptabilidade e estabilidade foram realizadas por meio de modelos que consideram o efeito de genótipo como fixo ou aleatório, em uma perspectiva de modelo misto. Observou-se interação significativa entre genótipos e ambientes para todos os caracteres avaliados. A linhagem CNFC 15086 apresentou as maiores GY e 100SW, além de alta adaptabilidade e estabilidade. A linhagem de maior destaque quanto à GA foi a CNFC 15038. A linhagem CNFC 15097 é a recomendada como cultivar (BRS FC406), por apresentar, simultaneamente, desempenhos favoráveis para GY, GA, SY e 100SW, bem como para adaptabilidade e estabilidade.

ABSTRACT The iron concentration (FeC) and zinc concentration (ZnC) in common bean grain are quantitative traits, and appropriate breeding techniques are required to achieve genetic gain. The aim of this study was to obtain a recurrent selection population of black bean to increase the FeC and ZnC in the grain and to select the superior progenies for formation of the next cycle and obtain lines. The base population was formed by crosses among ten parents. A total of 351 progenies were obtained, and, after two generations of selection, the 27 best progenies were evaluated in two field trials for FeC, ZnC, 100 seed weight and yield. Analyses of variance were carried out and genetic parameters were estimated. The heritability estimates ranged from 59 to 94% for the four traits. The estimates of expected gain from direct selection for each trait (3 to 21%) and simultaneous selection (1 to 4%) indicate success from selection. The eight progenies, selected based on simultaneous selection, have superior mean values, including to those of ‘BRS Supremo’ (10% for FeC, 8% for ZnC, 5% for 100 seed weight and 3.8% for yield), the Brazilian black bean cultivar with the highest FeC and ZnC. The recurrent selection population shows high genetic variability and potential for obtaining lines superior to the cultivars currently on the market, allying high agronomic performance and high FeC and ZnC in the grain. Furthermore, this population shows potential for generating a new recurrent selection cycle, from recombination of the eight superior progenies.

ABSTRACT: The root system architecture (RSA) of plants and its functioning play a fundamental role in a number of plant growth mechanisms including water and nutrient uptake. Optimization of the RSA is important for stable and increased plant productivity under adverse conditions. Despite its great importance, studying the RSA is notoriously laborious because of the difficulty of accessing the rooting system of plants. We developed a root phenotyping platform, PhenoRoots, which allows for the non-invasive study of plant RSA. The system was built using inexpensive material and was designed to provide medium throughput. Substrate or soil-filled rhizotrons are used to grow plantlets, whose roots are directly visible through a glass plate. An experiment conducted on a panel of twenty Upland cotton (Gossypium hirsutum L.) varieties demonstrated the usefulness of the platform in assessing RSA traits. A number of traits, destructive and non-destructive, related to the RSA were measured and statistically analyzed. The non-destructive traits based on image analysis of roots were more accurate and showed high correlation with the time-consuming destructive measurements. The platform allowed for capturing the phenotypic and genetic variability found in the panel of cotton varieties, and to define three contrasting RSA patterns. PhenoRoots provides an inexpensive alternative to the medium throughput analysis of RSA traits in plants.