Root distribution in common bean populations used in breeding programs

Abstract

This study aimed to assess the root distribution of mutant common bean populations along the profile and toselect bean genotypes with higher metric values for the trait root distribution, with a view to their inclusion in a bean breedingprogram. In this field study the genotypes IPR Uirapuru, IPR Chopim, Pérola and IAPAR 81 were evaluated and three doses(0, 100 and 200 Gy) of mutagen gamma rays (Co60), nested in the depths of the soil profile. A completely randomized designwas used with two replications. The trait root distribution was measured in the presence (1) and absence (0) of roots. Theexperiment was arranged in a mixed factorial design where the factors genotypes and doses were crossed and depth wasnested within the levels of these factors, and the regressions showed significant differences of the genotypes. Analysis ofvariance revealed an interaction of genotype x dose, nested in the factor depth of the soil profile, and the regressions showedsignificant differences among the genotypes. The most promising segregating populations were those derived from thecultivars IPR Uirapuru and Pérola, since with increasing mutagen doses their root number increased significantly.

Keywords

• Phaseolus vulgaris L.
• generalized linear models
• Bayesian analysis
• mutant populations
• abiotic stresses.