Alleviating drought stress in sesame seedling by priming and irrigation of beeswax waste and licorice extracts

In order to study the effect of priming and irrigation with beeswax waste and licorice extracts on germination, morphological and biochemical characteristics of sesame in drought stress condition, an experiment was conducted as factorial arrangement based on completely randomized design with four replications. The experimental treatments were drought stress (0, -2, -4 and -8 bar), priming (priming with water, beeswax waste extract at 2000 ppm and licorice extract at 5000 ppm) and irrigation with the extracts (water, beeswax waste extract at 2000 ppm and licorice extract at 5000 ppm). The results showed that the priming with beeswax waste extract caused to increase in percentage and speed of germination, seedling dry matter, radicle and plumule length, and CAT and APX activitie in drought stress condition, but MDA and proline contents were significantly decreased by that. Interaction of drought and irrigation showed that in drought stress condition, irrigation with beeswax and licorice extract led to increasing CAT and APX activities that consequently resulted to increasing seedling dry matter and radicle and plumule length. Interaction of priming and irrigation showed that the highest values of seedling dry matter (21.53 mg), radicle length (54.53 mm), plumule length (9.33 mm), CAT (0.377 unit mg-1 protein) and APX (0.557 unit mg-1 protein) activities was assigned to interaction of priming with beeswax waste extract × irrigation with licorice extract. Therefore, it seems that the most appropriate treatment for alleviating the negative effects of drought stress on sesame is pre-treatment with beeswax waste extract and irrigation with licorice extract.