The damage and the protection response of old leaves of mango under enhanced UV-B radiation.
Liu Peng, Zhou KaiBing, Pan XueFeng
Author Affiliation: Key Laboratory of Protection and Development Utilization of Tropical Crop Germplasm Resources, Ministry of Education, Hainan University, Haikou 570228, Hainan, China.
Plant Physiology Communications 46 : 787-792
Abstract : In a pot trial, the 12-month-old leaves from young mangoes (Mangifera indica) trees were irradiated under UV-B radiation for 0 (control), 2, 4, 6, 8, 10, and 12 minutes, respectively, 3 replicates for each treatment. Results of determination showed that after UV-B treatment, the content of malonaldehyde (MDA) and the relative conductivity were higher, while the content of chlorophyll and the ratio of chlorophyll a/b became lower. It indicated that the enhanced UV-B radiation caused the damages of leaves, which were even worse with longer treatment period. The UV-B treated leaves had higher contents of soluble protein, protective pigments (flavonoids, carotenoids) and reduced glutathione (GSH), higher activities of antioxidant enzymes (superoxide dismutase, catalase, and peroxidase), and lower content of ascorbic acid than the control, which indicated that the enhanced UV-B radiation induced elevated resistance of enhanced UV-B radiation in cells through intensifying the oxidant scavenging activities and absorbing part of the enhanced UV-B radiation.