Gibberellic acid priming effect on Agropyron elongatum seed germination indices under drought stress

Seed priming pretreatment improves germination characteristics, seedling establishment and increase of seed performance under environmental stress conditions. This experiment was conducted as factorial based on a completely randomized design with four replications using osmotic potential of -12 bar prepared by polyethylene glycol in order to evaluate the effects of gibberellic acid (GA) pretreatments on the behaviour of seed germination of Agropyron elongatom under drought stress.. Seeds were primed for 12 and 24 hours at two temperatures of 10 and 20°C with GA in three levels of 25, 50 and 100 ppm. All seed pretreatments had significant effect on the whole studied characteristics. Concentration of 25 ppm with GA was the best pretreatment which could increase significantly the whole germination percentage, normal seedling percentage, and length index of seedling vigor.The results obtained in temperature 10 and time duration of 12 were better in comparison to temperature 20 and time duration of 24 and significantly increased the germination and normal seedling percentage. Totally,the useful effects of seed pretreatment method with GA was confirmed for improving the seed germination performance of Agropyron elongatom especially in drought stress condition.