Abstract:

For the sake of discussing the physiological and ecological response and resistance difference to cadmium (Cd) of plants in different developmental stages under the intimidate of Cd, a pot experiment was conducted to study the dynamics of seedling growth and chlorophyll contents, SOD (superoxide dismutase) activities, POD (Peroxidase) activities and MDA (malondialdehyde) contents in leaves of Glycine max (Wu Yue Wang and Ri Ben Qing) under the stress of Cd in seedling stage, flowering-poding early stage and flowering-poding advanced stage, and comparative analysis the resistance of the two varieties to cadmium. The results showed that the most significant stimulating effects of Cd concentrations on the heights of Wu Yue Wang and Ri Ben Qing were 0.50 mg/kg and 0.25 mg/kg, respectively. Those on chlorophyll contents of Wu Yue Wang at seedling stage, early flowering-poding stage and flowering-poding advanced stage were 0.25 mg/kg, 0.50 mg/kg, 2.50 mg/kg, respectively. But, those on chlorophyll contents of Ri Ben Qing at different stages were all 0.25 mg/kg. At early flowering-poding stage, below 0.50 mg/kg of Cd, SOD activity of Ri Ben Qing rose slowly with the increase of Cd concentrations added in soil, but SOD activity of Wu Yue Wang basically changed quite slightly. The most significant stimulating effects of Cd concentrations on SOD activity of Wu Yue Wang and Ri Ben Qing at early flowering-poding stage were 2.50 mg/kg and 1.00 mg/kg, respectively. All the facts above showed that Ri Ben Qing was more sensitive to Cd stress at different developmental Stages than Wu Yue Wang.