Application of zeolite to alleviate of drought stress in rapeseed cultivars in Firoozkooh, Iran climate condition

To investigate the effect zeolite application in alleviation of drought stress in some rapeseed cultivars, a field experiment was conducted based on randomized complete block design in factorial-split plot experiment in Firoozkooh, Iran climate condition. Rapeseed cultivars consist of Kr18, Karaj1, Ks12, Goliath, Hyola401, Karaj2, Eagle, SW, Comet and Hyola420. Two factors including irrigation levels and zeolite application were placed in main plots and rapeseed cultivars assigned in subplots. Irrigation was applied in three levels of normal irrigation, irrigation cutting-off in flowering and podding stages. Zeolite applied as pre-plant in 8 tons/ha rate along with initial plowing adding to the soil. The yield components decreased under drought stress conditions and ultimately led to a significant decrement in seed yield. Application of zeolite resulted in increasing of seed yield and seed oil content. The highest seed yield was obtained in normal irrigation regardless of zeolite application. In zeolite application cases, the Kr18 cultivar had the highest yield, Eagle cultivar was better in case of zeolite lack. Therefore, in drought stress condition, it is recommended to use zeolite to prevent seed yield losses in rapeseed cultivars.