Role of Heme Oxygenase1 in Alteration of Antioxidant Defense Responses of Brassica juncea (L.) Czern. under Salt Stress Condition

Economically important crops are frequently facing many stresses, such as salt stress. They have developed an antioxidant defense network for preventing and repairing oxidative damage caused by salt stress. In this study, Brassica juncea seedlings were subjected to salt stress (NaCl) for time course analysis (1 st -5 th day) of heme oxygenase1 (HO1) activity along with other antioxidant enzymes. Treatment of salt induced lipid peroxidation and H2O2 content in root tissue as days of treatment increased. However, 1 st and 2 nd day of treatment did not modify these parameters, were similar to control values. HO1, Ascorbate peroxidase (APX), Peroxidase (POD) and Glutathione reductase (GR) activities were highest at 5 th day of treatment. Gene expression pattern of HO1 was similar as shown in biochemical analysis. These results showed that HO1 along with other antioxidant enzymes play an essential protective role against salt stress in B. juncea seedlings.