Relationships of Morphological Characters and Yield Components in Corn Hybrids under Water Deficit Stress

A split plot experiment (using RCB design) with four replications was conducted, in order to evaluate the response of some corn hybrids to water stress at field during 2010. Main plots included three different irrigation treatments (Non-water stress, Middle-water stress and Severe-water stress) and sub plots included 14 corn hybrids. In this study correlation, regression, path and principal components analysis wer e carried out to decide correlations among the agronomic traits and their contributions to seed yield per plant in some new corn hybrids. Correlation analysis indicated that there was the most significant and positive correlation between grain yield and row number per ear, grain number per row, ear height and plant height at the average of irrigation treatments. The results of stepwise regression and path analysis for grain yield revealed that row number per ear, 300 grain weight, grain number per row and number of leaves made 78 percent of the grain yield variation. The row number per ear had the greatest direct and positive effect on grain yield per plant. It is concluded that selection for high grain yield corn hybrids in water deficit stress conditions can be improved through this traits. Factor analysis showed that the first two factors would explain 78 percent of the total variation. This experiment showed that the hybrids K3647 × K18, SC400 and SC500 are more tolerant hybrids to water stress than that of other hybrids.