Genetic control of early grain darkening of carioca common bean

Abstract

To obtain information on the genetic control of early darkening in common bean with carioca grain and verifythe feasibility of selection by means of a grade scale, two contrasting parents were crossed, line VC-3 with cultivar BRSMGMajestoso. The seeds of F2 plants and F2:3 progenies were evaluated 30, 60 and 90 days after harvest for grain darkening, ona 1 - 5 grade scale. Genetic and phenotypic parameters were estimated. The grade scale efficiently discriminated the progeniesin terms of grain darkening. The heritability of the trait increases with the storage time and was high enough to ensure successwith selection after 30 days. The genetic control seems to be monogenic with dominance of the allele for early darkening.

Keywords

• plant breeding
• quantitative genetics
• grain quality
• heritability
• Phaseolus vulgaris L.