Realized response to different selection criteria in maize (Zea mays L.)

Abstract

Genotypic performance in maize (Zea mays L.), which is a sensitive crop, is greatly affected by variation in plant stand and soil heterogeneity particularly, during monsoon season. In the present study, 229 51 progenies of 'Composite Kesri' were evaluated and modified 51 selection among these progenies was carried out for high (HY) and low (LY) grain yield. Experimental varieties were developed by selecting among 51 progenies on the basis of analysis of covariance of grain yield for pl3nt stand and near neighbour (NN) corrections to account for the effect of soil heterogeneity on gain yield. Further, experimental varieties were also developed on the basis of superiority of plot and plant yield of 51 progenies in comparison to the adjacent row of balanced male (8M) composite. The objective was to identify the approach that most favourably affects the response to selection. The resulting experimental varieties were evaluated in six environments. Analysis of variance showed significant differences among experimental varieties and original Kesri for all the traits studied. Selections were effective for HY as well as LY. In case of selection for HY, the experimental varieties developed by selecting on the basis of plot yield in comparison with 8M composite, gave numerically, the highest yield followed by the variety developed on the basis of selection for plot yield corrected by analysis of covariance for plant stand, and these both gave significantly higher yield than Kesri. Overall consideration of direct and correlated response to selection for HY and LY indicated that selection for yield may be more effective when based on superiority in plot yield over adjacent rows of 8M cpmposite.