Effects of Cr~(6+) Stress on Physiological and Biochemical Properties of Soybean Seedlings

By the method of solution culture,and with the soybean(Glycine max L.) cultivar Yudou No.24 as experimental material,this paper studied the effects of different Cr6+ concentration on the physiological and biochemical characteristics of soybean seedlings.The results showed that with the increasing Cr6+ concentration supplemented in solution,dry weight of root and shoot,ratio of root to shoot,chlorophyll content,ratio of chlorophyll a to chlorophyll b and superoxide dismutase(SOD) activity in soybean seedlings all decreased,whereas malondialdehyde(MDA) content and peroxidase(POD) activity increased gradually.Furthermore,the inhibition of Cr6+ stress to root was more serious than to shoot,and chlorophyll a was more sensitive to Cr6+ stress than chlorophyll b.Under lower Cr6+ concentration(10 mg/L) stress,root and shoot dry weight,ratio of root to shoot,chlorophyll content and SOD activity were not inhibited obviously,and MDA content increased slightly,suggesting that Yudou No.24 could tolerate the lower Cr6+ stress to a certain extent.