Generation Mean Analysis for Yield and Drought Related Traits in Maize (Zea mays L.)

Abstract

Six generations of two maize crosses were used for computation of generation mean analysis under moisture stressed and non-stressed conditions for yield and drought related traits. Epistasis was observed for all the traits studied in two crosses in both the moisture conditions. The traits number of kernel rows per cob, number of kernels per row, number of grains per cob, grain yield, chlorophyll content and anthesis to silking interval depicted the duplicate gene action under both non stress and moisture stress condition for both the crosses. However relative water content depicted complementary gene action for the cross CIL1221×ZL11243 under both the moisture regimes. Although leaf area index exhibit complementary gene action for cross CAL1411×CZL0713 under both the moisture regimes. In the presence of epistasis, complementary type of gene interaction situation, additive component is often relatively underestimated while dominance effects tend to be overestimated. Duplicate type of epistasis generally hinders improvement through selection and selection of these traits will be difficult in the early generations. Therefore selection should be delayed after several generations of selection (single seed descent) until a high level of gene fixation is attained. Such genotypes could stand better under drought conditions to get maximum yield in maize.