Response antioxidant enzymes, lipid peroxidation and cell death of rice cultivars to salinity stress

A factorial experiment in hydroponic conditions was conducted to evaluate the activity of antioxidant enzymes, membrane stability and Na concentration in seedling of some rice cultivars, in 2014 summer in Ramin Agriculture and Natural Resources University of Khuzestan. Experimental factors were included salinity levels of NaCl (0, 4 and 8 ds.m-1) and rice cultivars (Amol3, Daniel, Shafagh, Fajr and Red Anboori). Some attributes including, hydrogen peroxide, malondialdehyde, peroxidase, electrolyte leakage, Na concentration and shoot dry weight were measured. The result showed that salinity levels significantly decreased shoot dry weight and increased antioxidant enzymes, membrane peroxidation, electrolyte leakage, and Na concentration. Rice cultivars responded differently to salinity levels. Red Anboori and Amol3 Cultivars had the highest antioxidants and the lowest lipid peroxidation. These two cultivars in control condition had lowest shoot dry weight (5.15 and 5.51 g.plant-1). However, these cultivars had no significant difference with other cultivars in 8 dS.m-1 salinity condition. On the other, Danyal and Fajr cultivars were obtained greatest reduction in shoot dry weight under severe stress (51.9 and 49.4 percent respectively). So Red Anbory and Amol 3 cultivars by increasing enzymatic defense system and reduce damage to cell membranes as tolerant cultivars at the seedling stage compared to another cultivars will be introduced.