Effect of seed priming on germination characteristics and some antioxidant enzymes activity of Basil (Ocimum basilicum L.) under drought stress conditions

Seed pre-treatment technique has been introduced as a germination and establishment enhancer under environmental stress. In order to study the effects of priming on germination characteristics growth and some antioxidant enzymes activity of basil (Ocimum basilicum L.) under drought stress conditions, a factorial experiment in a completely randomized design with four replications, at the physiology lab of the Islamic Azad University of Ardebil in 2013 was carried out. Experimental treatments include drought stress at four levels (0, -4, -8 and -12 bar) and three pre-treatments including potassium nitrate with concentrations of 1% and 2%, water as hydro priming and control treatment. The results showed that the effect of drought stress and priming on germination components and antioxidant enzymes was significant. The results showed that drought stress reduced the percentage of germination, pace of germination, rootlet length, seedling length and increased activity of superoxide dismutase, glutathione peroxidase, catalase and ascorbate peroxidase enzymes. The results of the comparison of mean interactions of drought stress and priming showed that the maximum activity of Antioxidant enzymes were obtained by pre-treatment of potassium nitrate with a concentration of 1% in a -12 bar drought level. In general, it can be concluded that basil seed pre-treatment with 1% potassium nitrate improves the basil germination parameters under drought stress conditions and increased the tolerance of basil plant to drought stress by increasing the activity of antioxidant enzymes in the germination stage.