Investigation on allelopathic potential of Zhumeria majdae Rech essential oil on two wheat cultivars

Zhumeria majdae Rech. has been used as traditional medicine in southern part of Iran. Essential oils and extracts from different parts of the plant have allelopathic effects. Present study investigated allelopathic effects of Zhumeria majdae Rech. essential oil on germination percentage, pigment content (chlorophyll and carotenoid) and antioxidant enzymes (catalase and Guiacol Peroxidase) activities on two wheat cultivars, Azar2 and Sardari. Plants were grown in perlite and the 10- days treated plants were used for the measurements. Different concentrations of the essential oil were obtained by 2.5% Arabic Gum solution. Distilled water and 2.5% Arabic Gum solution were used as control. Results indicated that germination percentage, pigment content, and the two antioxidant enzymes activities of the species treated with Arabic Gum were equal to those of the species treated with distilled water. With increasing essential oil concentration, in both cultivars, the germination percentage and chlorophyll content decreased and the carotenoid content increased. In the presence of essential oil, catalase activity increased slightly in both cultivars. In conclusion, it could be stated that incremnet of pigment content and antioxidant enzymes activities reduce their harmful effects on growth and development of the species through lowering the Reactive Oxigen Species (ROS) concentration.