effects of genotype by environment interactions on morphological traits, yield and yield components of new grain corn (zea mays l.) varieties

in this study 18 corn hybrids consist of 15 new early and mid mature foreign hybrids and three commercial iranian corn hybrids (ksc704, ksc647 and dc370) as controls were evaluated at two rcbd with three replications at the khorasan razavi agricultural research and natural resources center, during 2008 -2010. results showed that hybrid exp1 and dc370 with 16.5 and 12.1 t.ha-1 were the best and the worst hybrids, respectively. also, the exp1 hybrid was better than others for no. rows, kernel depth, ear length and stem diameter. the results of simple correlation showed positive and significant correlations between grain yield with plant height, ear height, no. rows kernel depth, days to physiological maturity, ear length and leaves no. also, we estimated negative correlation between grain yield and cob percentage. results of cluster analysis by wards’ method based on two years data showed that these corn varieties can be divided in four clusters.