Enhancement of senescence in excised rice leaves by hydrogen peroxide

Publisher Website
Google Scholar
Abstract
Changes in the catalase activity and the effect of hydrogen peroxide (H2O2) were studied during the senescence of excised rice (Oryza sativa L. cv. Ratna) leaves. Catalase activity declined upon detachment of leaves. Regression analysis showed a strong positive correlation between the decline in the catalase activity with the decline in the soluble protein content (r = 0.9827; n = 13). Infiltration of H2O2 into the leaves accelerated chlorophyll loss and α-amino nitrogen accumulation. Infiltration of glycolate or xanthine (serving as substrates for the formation of H2O2) into the leaves had a similar effect. Application of aminotriazole, a strong inhibitor of catalase, also accelerated the senescence of excised rice leaves. These results indicate that leaf senescence can be accelerated by increasing the endogenous H2O2 level in the leaf tissues.