Effects end of seasonal drought stress on germination parameters and seedling heterotrophic growth of wheat cultivars

In order to investigate the effect of drought stress on germination parameters and heterotrophic growth of different wheat cultivars, a factorial experiment was carried out in a completely randomized design with 6 replications in a research greenhouse of Faculty of Agriculture and Natural Resources, University of Gonbad-e- Kavous in 2016-2017 .The treatments were included wheat cultivars in 5 levels (Aftab, Qaboos, Kohdasht, Karim and Line 17) and drought stress in four levels (full irrigation as the control, slight water stress (25% water depletion of field capacity) , intensive water stress (50% water depletion of field capacity) and very intensive water stress (75% water depletion of field capacity). The results of this experiment showed that maternal drought stress was significant only on radicle dry weight, plumule dry weight and seed vigor. There was a significant positive correlation between plumule dry weight, plumule length and seed vigor. It can be said that drought stress can greatly affect the seed vigor of different wheat cultivars. So that seed vigor of different cultivars was different at each stress level. The effect of cultivar was significant on all traits except radicle dry weight. Therefore, germination and seedling growth were more affected by cultivars. Regarding the negligible effect of drought stress on most germination traits, it can be concluded that genetic than environment (maternal drought stress) had a more effective effect on germination and heterotrophic characteristics of seedlings of wheat seeds