Genetic Variability and Heritability Estimates Based on the F2 Generation from Crosses of Large-Seeded Virginia-Type Peanuts with Lines Resistant to Cylindrocladium Black Rot1

Abstract

Abstract Selection of large-fruited, high-yielding Cylindrocladium black rot — (CBR) resistant lines from two sets of crosses, each set consisting of crosses in F2 generation between a virginia and two CBR-resistant lines, was evaluated to determine the potential for selecting cultivars with these traits. Heritabilities, phenotypic and genotypic correlations and estimates of additive and nonadditive genetic effects were determined for yield and fruit traits at two locations and CBR resistance at one location. Crosses with NC 2 as a parent had higher levels of CBR resistance than those with Florigiant as the common virginia-type parent. Heritability estimates for the necrosis index (CBR resistance) were high while estimates for yield and fruit traits were variable over crosses and locations. The necrosis index was significantly and negatively correlated with all fruit and yield traits for three of the four crosses indicating it should be possible to select high-yielding, largefruited lines with low levels of disease from three crosses. Only significant additive genetic effects were found for CBR resistance. Significant additive and nonadditive genetic effects were found for the yield and fruit traits. Estimates of additive and non-additive genetic effects indicate that early generation selection for CBR resistance should be effective, whereas selection for yield and fruit traits would be more effective in later generations.