Abstract
A decrease in catalase activity is a key factor increasing salt stress-induced oxidative injury in rice seelings. Catalase activity is inhibited by salicylic acid (SA). NaCl treatment increased SA content in rice seedlings. On the contrary, in Echinochloa crus-galli seedlings which are tolerant to salinity, SA content did not increased. Rice and E. crus-galli seedlings were treated with NaCl after SA application. No significant difference in growth and ΦPSII was observed between SA treated and non-treated rice seedlings under salt stress. On the contrary, SA pre-treatment enhanced the reduction of growth and ΦPSII in E. crus-galli seedlings. Moreover, in E. crus-galli seedlings, SA + NaCl treatment caused a decrease in catalase activity and an increase in superoxide disumutase. It was suggested that SA accumulation is involved in the change in antioxidative enzyme activity, resulting in the induction of oxidative injury.
