Grouping of Late Maturing Corn Hybrids in Relation to some Agronomic Traits

Study the relationships of some agronomic traits with grain yield of 14 late maturing corn hybrids, an experiment based in RCBD with four replications was carried out at Miyandoab Agricultural and Natural Resources Research Station in 2009. Results showed that there were significant differences among corn hybrids for plant and ear height, number of kernel row and kernel numbers per ear, 1000 kernel weight, biological yield and grain yield. Hybrid KLM76005 × MO17 produced highest grain yield. Grain yield had high positive significant correlations with biological yield and harvest index. Stepwise regression analysis showed that traits like harvest index, biological yield and 1000 kernel weight justified the grain yield variation. Path analysis indicated that these traits had the highest positive direct and significant effect on grain yield. Based on the cluster analysis results, corn hybrids under study divided into 5 groups. Groups number 2 and 3 in cluster analysis did have higher mean values for effective traits on grain yield (harvest index, biological yield and 1000 kernel weight) as compared to the others. Grain yield had negative significant correlation with GDD at tasseling time and total GDD during growing season. Based on principle components analysis basic vector values two factors explained data total variation by 80.3 %. Based on results obtained it can be concluded that Hybrid KLM76005 × MO17 due to its higher biological yield and harvest index would be the best option to be recommended.