Evaluation of Drought Tolerance Indices of Grain Maize Hybrids under Deficit Irrigation

Decrease of water resources in temperate regions of Kermanshah province has caused the maize cultivation area decreased form 45 thousand hectares in 2008 to 7 thousand hectares in the crop year of 2016. This study aimed to evaluate and selecting drought tolerant hybrids and increased irrigation water efficiency using eight commercial maize hybrids (KSC 704, KSC 705, KSC 703, KSC 700, KSC 647, KSC 670, KSC 500, KSC 400) in a randomized complete block design in 2013 and 2014. Irrigation practices consists of two levels: The first level was equal to100% of the corn crop water requirement based on meteorological data of Islamabad station and Second level was 70 percent of the corn crop water requirement. Measured traits including plant height and ear height, stem diameter, days to emergence of tassel ling, silking and physiological maturity, number of kernels per row, rows per ear, kernel depth, moisture content, percentage of cob, thousand kernel weight and grain yield. Correlation matrix analysis showed that correlation between two treats was significant at one percent and 13 treats were significant at the five percent. The correlation between the number of rows per ear, number of kernels per row and grain yield, were significant and positive with 0.839*, 0.933**, 0.831*, respectively. Based on the criteria of tolerance and sensitivity to stress as well as the results of bi-plot display and view the status of being genotype and indexes, cultivars (KSC 647), (KSC 703)as the most tolerant genotypes suitable for both stress and no stress and Hybrid(KSC 705) as the most high-yield in varieties were identified in normal conditions. KSC 700 genotype was evaluated as the most susceptible genotypes.