Allelopathic potential of Zhumeria majdae essential oil on brassica napus (Talaye cultivar)

The present study investigates the allelopathic potential of Zhumeria majdae essential oil on acanola cultivar, Talaye. Essential oil was extracted by water distillation method, and was dissolved in 1% Arabic gum to achieve required concentrations. Catalase and Guiacol peroxidase activity in the presence of gum Arabic were the same as control; so gum Arabic did not affect enzyme activities. By increasing essential oil, the chlorophyll content decreased but the carotenoid content increased. Guiacol peroxidase activity in the presence of essential oil increased 20 and 60 percent but the increasing trend stopped in 60% of essential oil. Catalase activity increased significantly in the presence of 100% essential oil relative to control. Since relative oxygen species (ROS) increase in the presence of different concentrations of essential oil, plants increase guiacol peroxidase and catalase activity to decrease the ROS concentration, and thus, reduce their harmful effects on growth and development.