Bayesian analysis of the genetic control of survival in F3 families of common bean

摘要

The objectives of this study were to examine the genetic control of survival in segregant families F₃ of the common bean ( Phaseolus vulgaris L.) in southern Brazil during the 2004-2005 growing season, to identify useful genotypes for the breeding program of this crop, and to determine the genetic association between survival and weight of 100 seeds (production trait; P100). A Bayesian approach was used to predict breeding values and to estimate variance components. Survival was recorded as a binary response: dead plant or live plant during harvest. The total population consisted of 11,520 individual plants. The difference in the magnitude between the best and the worst families was as high as 22%, and varied from 57 to 73%. Survival was found to be highly heritable, with an a posteriori heritability mean and Bayesian credible interval: H2 = 53% (43-65%). The genetic advance by direct selection achieved a value of 18%, considering a selection intensity of 25%. Survival was not correlated with P100 (Pearson = 0.099; Spearman = 0.074), indicating that selection for this trait alone would have little impact on production from a breeding viewpoint. Bayesian analysis, using the Gibbs algorithm, was useful in the genetic evaluation of common bean families based on a binary response variable.