Effects of Drought drought Stress stress and Irrigation irrigation Methods methods on Yyield and yield Ccomponents in Corn two Hhybrids of Ccorn (Zea mays L.) Yield and Its Components

An experiment was carried out under drought stress condition and two irrigation methods were used to evaluation of yield and its components of SC70 and SC67 corn varieties. A complete random complete block design with tree replicates as split plot was used at the Aagricultural Rresearch farm. Stationof Karajof, Islamic Azad University, Karaj Branch (5°´ N latitude, 50° 56´E longitude, 60m altitude) in 006 and 007. Main plots consisted were allocated to drought treatments thatwhich were applied in at 0%, 60% and 75% levels of soil soil watemoisturer loss depletion, sub-polts toand two levels of irrigation methods in levels (iIrrigation of all furrows and irrigation furrows alternately) and sub-sub plots to t. Two cornhybrid varieties varieties also used as a sub plot treatments. The rResults showed that drought stress had significant effects on yield and its yield components and sever water stress treatment (75% moisture depletion) caused to 7% yield reduction in yield. Two iIrrigation methods didn’t have any significant effects on grain yield, but however a significant interaction effects of genotype and watre stress was observed, whereas the hybrid had significant difference. SC67 produced more yield in full irrigated was more successful in irrigation of all furrows completely andbut hybrid SC70 produced more yield in the alternative irrigatedion furrows alternately. Indeed, SC70 produced yielded more than SC67 in under water deficit condition when all furrows were irrigated. There was a significant positive correlation between grain yield and with biomass, grain weight (r = 0.67), grain number in cob plant row, grain number in cob plant row (r = 0.7), plant height and a negative correlation with also inoculated part of cob negatively (r = -0.76).