Using correlation and some genetics methods to study of morphological traits in corn (Zea mays L.) yield and yield components under drought stress condition

ABSTRACT: In order to study the effect of drought stress on morphological characteristics, yield and yield components of 18 new hybrids of corn (Zea maize L.) resistant to drought stress and warm (which were bred and screened in Khozestan province condition) and 6 commercial and promising genotypes as control, an experiment was conducted in a Randomized Complete Block Design (RCBD) with three replications under drought stress and normal irrigation at Khorasan-Razavi Agriculture Research Center, Mashhad, Iran on June 10, 2010. The results of analysis of variance showed that under normal irrigation and drought condition, there was a significant difference between the hybrids. Mean comparison of hybrids revealed that in normal irrigation KSC50 single cross hybrid and in drought stress 11 no. hybrid had the maximum grain yield. The effect of drought stress on leaf no. /plant and ear no. / plant was positive, while its effect on other traits was negative. The highest reduction of grain yield was observed in drought condition compared to normal irrigation. For the measured traits in normal irrigation and drought stress, genetic characteristics such as genotypic and phenotypic variations coefficients and heritability were calculated. Results revealed that under drought stress condition, the heritability of grain yield was increased about 45 percent.