The effect of drought stress on the seed germination of Calotropis procera L. and improvement of drought tolerance

Calotropis procera seed's has poor germination in field condition. Seed germination is a critical stage of species survival. To investigate the effects of drought (Kcl, KNo3 and PEG-6000-respectively) on seed germination a factorial experimental plans was conductec in a completely randomized block and factoriel design with three replications. In the first experiment, the main factors were 2 levels of treatment (non prim and prim) and 9 levels of drought of Kcl and KNo3 (0, -1, -3, -5, -7, -9, -11, -13, -15 bar) and 6 levels of drought PEG (0, -0.1, -0.3, -0.5, -0.7,-0.9 bar). The experiment includes two environments (Lamerd and Sistan-Baluchestan). The results indicate that the effect of the drought levels is significant on seed germination properties; however, environment has not significant effects on germination rate and its percentage. Any increase in the drought stress reduces the seed germination rate, the corresponding percentage seedlings length, the pre-treatment using. Results showed that germination percentage, germination rate, seedling dry weight and seedling length. Using common solution (Kcl -20 bar, KN03 -20 bar, PEG -1 bar) as a pre-treatment of the seeds for 3 days period will enhance the germination properties.