The effect of chitosan on some physiological and biochemictry characterization in basil (Ocimum basilicum)

Basil (Ocimum basilicum) is a medicinal plant of the family of Lamiaceae. It contains phenylpropanoid and terpenoid componds. Chitosan with elicitor action induce defence mechanisms of plant. In the present study، the effect of chitosan on malondialdehyde (MDA)، hydrogen peroxide (H2O2)، gayacol peroxidase (GPX)، peroxidase (POD) and poly phenol oxidase (PPO) antioxidant enzymes activity، phenol compounds، flavonoids، antosyanin، chlorophyl a، b and carotenoid، soluble sugars and proline was evaluated. The plants were treated at pre flowering stage with 2 g/L chitosan and harvested after 1، 2، 3، and 5 days after chitosan. Comparing with control، the results showed that MDA and H2O2 increase in shoot in different harvest stages under treatment with chitosan. Also antioxidant enzymes activity، phenol compounds، flavonoids، antocyanin، chlorophyll a، b and carotenoid، soluble sugars and proline، in comparison with control، increased in many cases in different harvest steges. So it seems that chitosan، as a biotic elicitor، enhanced antioxidant enzymes activity and secondary metabolites production.