Study on grain yield and related traits in new corn (Zea mays L.) hybrid varieties using statistical multivariate analysis

In this study 18 new corn varieties consist of 15 foreign early and mid mature single cross hybrids and 3 Iranian commercial hybrids (KSC704, KSC647and DC370) were evaluated at two sowing date (5 and 20 June) based on RCBD with 3 replications at Khorasan Razavi Agricultural Research Center, Mashhad, Iran on 2008 and 2009. The results showed significant differences between hybrids, years and different sowing dates. Means comparison using Duncan’s multiple range tests showed that the best hybrid in total yield was EXP1. Further, DC370 and OSSK602 had the lowest grain yield. Results showed that the 5 June sowing date was better than 20 June about kernel no./row, 300-kernel weight, kernel depth and grain yield traits. Simple correlation coefficients showed that the yield was positively and significantly correlated with plant height, ear height, kernel no./row, ear length and leaves number traits. Using principal component analysis were identified four and four components of variance (with 69.75 and 69.45 percentage). Results of cluster analysis using Wards’ method divided the corn hybrids into several different clusters.