اثر تنش رطوبتي بر جوانه زني سه گونه اسپرس

The effect af water stress on germination and growth was studies in three species of Onobrychis spp. Drought stress was formed by using polyethyllene glycol 6000 (PEG) solution with potential produced different effects, both in germination percentage and speed, length, weight and alometric coefficient of radicles and plumule. This study was conducted as a factorial experiments with randomized complete block design with three replications. The species factor in three sublevels and the osmotic potential were studied in six sublevels. The data were analysed using permutation radical. The effect of water stress on evaluated characteristes was highly significant and minimum germination percentage was average 89% and 47% for O. sintenisii and O. melanotricha respectively. Germination speed for O. sintenisiti with average 38 seed in day was obtained the first level. Average comparison of length of roots alometric coefficient on O. melanotricha in level 1 % with species two sainfoin significant. This might be attribute to the effect of endosperm and seed size. Since orie of limitation factor for rangeland plant establishment is water, deletion on the germination period, therefore this study would be useful for detection of drough tolerance plants.