Effect of exogenous Gly on the growth and oxidative damage of alfalfa seedling under Cd stress
外源甘氨酸对镉胁迫下苜蓿幼苗生长和氧化损伤的影响

Protective effects of Gly against Cd toxicity in alfalfa seedlings were investigated. Cd toxicity reduces the activity of SOD and CAT, resulting in oxidative damage such as high MDA content and Evans blue uptake by alfalfa seedling root. Supplementation of Cd with Gly increases SOD and CAT activity and decreases MDA accumulation, thereby reducing oxidative damage in alfalfa seedlings. Cd treatment also reduces NR activity while Gly enhances NR activity in Cd-treated alfalfa seedlings. On the other hand, tungstate (NR inhibitor) supply reverses the effect of Gly by decreasing NR activity and inhibiting seedling growth. The results suggest that enhanced Cd tolerance by Gly treatment is correlated with increasing activities of antioxidative enzymes and NR in alfalfa seedlings.