Relationship between Yield and Other Agronomic Traits in Maize Lines and Hybrids

In order to study the relations between yield and yield components of maize, seven inbred lines and seven hybrids progenies of crossing between them and four open pollinated F1 hybrids: SC 301, SC 604, SC 647 and SC 704 were grown in an unbalanced grouped design with three replications. The analysis of variance showed significant difference among groups for most of studied characters that indicated the existence of genetic variation among varieties. Genotypic correlation coefficients indicated that grain yield had a significant positive correlation with kernel number per row, number of kernel rows per ear, kernel depth, and plant height as well as with % oil. Also, grain yield had a significant negative correlation with % protein. Considering grain yield as a dependent variable, while using stepwise regression analysis, 92.2% of grain yield variation was attributed to two traits, kernel number per row and row number per ear and the model was significant at 1% probability level. Path coefficients analysis showed that the kernel number per row had highest direct effect. This trait had negligible indirect effects through kernel row number. Genotypes and traits were classified in three clusters by cluster analysis. In conclusion the most important traits contributing to grain yield in corn were kernel number per row and row number per ear which could be used for indirect selection of grain yield.