Mechanisms of selenium improving the resistance of rice to ferrous toxicity

摘要

In this study, pot experiment was conducted to study the mechanisms of selenium (Se) on scavenging excessive free radicals, and on alleviatiag membrane lipid peroxidation of rice under ferrous (Fe) stress. The activities of ascorbic acid peroxidase (AsA-POD), giulathione reductase (GR), glutatione peroxidase (GSH-Px), the contents of reduced glutatione (GSH), malondialdehyde (MDA) in rice leaves, and 1000-grain weight of rice, grain filling rate, as well as rice yield were measured. Compared with ferrous stress, in Se1 treatment the activities of AsA-POD and GR increased by 53% and 27% in tillering stage, significant at P=0.05, GSH content increased by 63%-82%, significant at P=0.05 in every stage, MDA content in the rice leaves in Sel treatment decreased by 12%-32%, significant at P =0.05, and decreased by 7.5% in the tillering and by 24% panicle stage in Se2 treatment. Compared to no-Se control, adequate Se nutrition increased 1000-grain weight of rice by 1.77 g, significant at P=0.01, grain filling rate by 3.3 percentage points, significant at P = 0.05, and yield from 86.80 g to 91.74 g per pot.