effect of seed priming on germination and seedling growth of the caper (capparis spinosa) under drought stress

objective: to evaluate the effect of chemical stimuli on germination and seedling growth of caper (capparis spinosa) under drought stress. methods: factorial experiment in a completely randomized design with four replicates per treatment were performed. first factor of priming include three levels of acetylsalicylic acid (300, 200 and 100 mg/l), gibberellic acid levels (500, 250 and 125 ppm), ascorbic acid levels (300, 200 and 100 mg/l) and distilled water as a control and the second factor was drought stress levels (0, -0.3, -0.6, -0.9 and -1.2 mpa). results: the results showed that priming increases germination rate, germination percent, root length, seedling length, shoot length and seed vigor index under drought stress. among of levels used in priming, acetylsalicylic acid 200 mg/l has greatest effect on the germination of plants under drought stress. according to the survey results, priming with salicylic acid compared with other acids have more effect on germination characteristics of caper under drought stress. conclusions: thus, using of this method can be useful for improving seed germination characteristics of plants in arid and semi-arid regions.