Allelic Frequency Change of P1 Gene in Maize Population After Recurrent Selection for Grain Yield

Abstract

Full‐sib family recurrent selection for grain yield was conducted for four cycles in maize (Zea mays L.). The source population was the F2 of A632 (with red cob) ×195 (with white cob). Objectives of this research were to evaluate the change in allelic frequency at the P1 gene (determining cob color), to assess whether this change was due to random drift only, and to detect whether allelic frequencies were correlated with grain yield responses. The source and the four selected populations were crossed to two inbred lines with white cob (recessive trait). The frequency of red cob allele increased with selection following a highly significant linear trend (b = 0.066 cycle−1), suggesting the effect of directional selection. Correlation between allelic frequency and grain yield was significant for populations as S2 generation (r = 0.938), and as testcrosses (r = 0.886), and could be ascribed to fight linkage, to pleiotropy, or both.