Inheritance of root distribution in common bean and selection strategy

Abstract

The objective was to determine the predominant genetic inheritance in the trait root distribution in common bean and define the selection strategy. An experiment involving 40 genetic constitutions (segregating and fixed populations), was developed during the agricultural years 2014/15 and 2015/16. The experiment was arranged in a Federer's augmented block design with 3 replicates. The root distribution was evaluated by Bohm method. Estimates of mean contrasts between the F 4 progenies and their parents did not reveal any significant differences in any comparison. The generations F 5 and F 6 presented the same behavior. The distribution of the component of the additive genetic variance was similarly conducted for the segregating generations. Thus, since the predominant inheritance of the root distribution is additive, the selection of this trait is recommended to be performed at the end of the breeding program.

Implications of additive x additive epistasis for common bean breeding

“…Previous experiments with autogamous plants have shown the predominance of additive effects on inheritance of root traits(Kashiwagi et al 2008;de Melo et al 2016de Melo et al , 2018) and shoot traits(Toledo et al 2000). Likewise, an additive x additive component was detected in the genetic control of root length and root dry weight for chickpea(Kashiwagi et al 2008), as well as for ve root traits of common bean, in the cross of the genotypes ICA Pijao x Ouro Negro(Araújo et al 2005).…”

Research Article Genetic structure of root distribution in genotype crosses of Mesoamerican common bean

“…For chickpea (Cicer arietinum), a crop of the same botanical family as common bean, a study based on generation means found that the additive and additive x additive effects play an important role in the genetic control of the root system (Kashiwagi et al, 2008). In common bean, based on the complete diallel cross design, comparisons between the means of the parents and those of the segregating generations supported the assumption of predominant additive inheritance of the trait root distribution (de Melo et al, 2016(de Melo et al, , 2018. In addition, it has been found that heterosis is not fundamental for root distribution, even when plants of different gene groups of common bean are crossed; the authors suggested that possible epistatic effects influence this trait (Grigolo et al, 2021).…”