Cadmium stress in Dongying wild soybean seedlings: growth, Cd accumulation, and photosynthesis

In order to understand better Cd resistance in soybean, Dongying wild soybean treated with different Cd concentrations were evaluated. The biomass, chlorophyll (Chl) content, leaf color, Chl a fluorescence parameters, photosynthesis parameters, and Cd contents were determined. Our results showed that when Cd concentration was ≤ 2 kg m –3 , no significant decrease in biomass, photosynthetic parameters, and maximal photochemical efficiency of PSII was observed. This indicated that Dongying wild soybean resisted Cd toxic effects under such conditions. In addition, atomic absorption experiment results demonstrated that when Cd concentration was ≤ 0.5 kg m –3 , the accumulation of Cd in wild soybean was lower in roots than that in shoots, while the accumulation of Cd was higher in roots than that in shoots when Cd concentration was ≥ 1 kg m –3 . Therefore, Dongying wild soybean showed a certain resistance to Cd and could serve as a valuable germplasm resource for improving the breeding of Cd-resistant soybean.