Hybrid Performance Among Six‐Rowed Winter Barleys (Hordeum vulgare L.) Varying in Kernel Size1

Abstract

A large‐kerneled, 6‐rowed, winter barley (Hordeum vulgare L.) cultivar (P1) was crossed as the maternal parent with seven 6‐rowed, winter barley cultivars varying in seed size (P2 through P8) as pollen parents. The seven F1 hybrids were compared with the eight parents at Columbia, Mo., in 1968‐69. Heterosis for kernel size was indicated in specific crosses with five of the seven F1's exceeding their respective midparents and four of the F1's exceeding their respective highparent for both percentage of plump kernels and kernel weight. As an average over all crosses, the F1's exceeded the midparent for survival, early maturity, height, lodging, grain yield, tillers per plant, and kernels per spike in addition to kernel plumpness and kernel weight. Correlation data confirm the close association of kernel plumpness and kernel weight as measures of kernel size and the independence of these kernel size measurements from the other agronomic characters studied. The genetic potential for improvement of kernel size and kernel plumpness is demonstrated by heritability estimates of 0.886 and 0.710, respectively, for these two characters.