Genetic analysis of grain yield and oil content in two maize populations

Background and purpose: The objectives of this study were to estimate correlations between kernel oil content and morphological traits in two studied maize populations, and to estimate direct and indirect effects of yield components on kernel oil content. Materials and methods: The material for this study was developed by crossing progenies of high oil maize populations with two testers. The traits analyzed were kernel row number; 100-kernel weight, grain yield per plant and kernel oil content. Correlation coefficients were based on the ratio of joint variation and summary of individual variation of two traits (8). Standardized partial regression coefficients and levels of their significance were calculated according to the method of the inverse matrix (10). Results: In B73 testcrosses, oil content was in negative, and medium strong correlations with all studied traits were observed. In the second population, relation between these traits was also negative, but medium strong and weak between oil content and kernel row number; and between oil content and other studied traits. Significantly positive coefficient of correlations was found between grain yield and 100-kernel weight in both estimated populations Conclusions: Coefficients of correlations between kernel oil content and other traits were estimated. Significantly negative direct effects were estimated of all studied traits to kernel oil content but indirect effects were significantly positive and negative