Assessment of the Hazardous Effects of Cd on Physiological and Biochemical Characteristics of Soybean Genotypes.

Heavy metal contamination in soil has become a serious problem, and cadmium (Cd) in particular is of increasing global concern due to its readily taken up by plants. The selection of plant genotypes with low Cd uptake in roots and its transport to edible parts is a realistic approach to alleviate adverse effects of Cd contamination. In view of these considerations, series of experiments were performed to identify the genotypic difference in physiological and biochemical characteristics of soybean genotypes by applying different Cd concentrations. Twenty three soybean genotypes were grown at 0 and 2.0 µmol L-1 Cd in nutrient solution to compare the difference in Cd tolerance. Biometric, physiological and biochemical parameters revealed better performance for S951-3 and high sensitivity of Q17-3 to Cd toxicity. S951-3 and Q17-3 were used in the succeeding experiment to investigate the mechanisms of Cd tolerance in soybean. The Cd (5.0 µmol L-1) reduced growth, chlorophyll content and photosynthetic rate in both genotypes, but the extent of reduction was different. Cadmium, MDA contents, and activity of antioxidant enzymes were significantly increased with Cd treatment, being higher in Q17-3. These data suggest S951-3 as more resistant genotype than Q17-3 to Cd stress. © 2014 Friends Science Publishers [ABSTRACT FROM AUTHOR]