Stress Effect and Response Mechanism of Cd2+,Cu2+,Zn2+ and Pb2+ on Potamogeton crispus L.Growth
To estimate the influence of different heavy metals to the Potamogeton crispus L.,especially the growth and development of its winter buds,the stresses of Cd2+,Cu2+,Zn2+ and Pb2+ in different concentrations to the growth and development of winter buds of Potamogeton crispus L.were studied,through the quantitative determination of germinated number of winter buds,chlorophyll of the leaves,soluble protein,malondialdehyde (MDA),and antioxidant system.As a result,under the same concentrations,Cu2+ had the most obvious effect on physiological and biochemical indexes of the plant.The Cd2+ ranked the second and followed by Pb2+ and Zn2+.The plants cannot grow normally or even survive with concentration of Cu2+ or Cd2+ higher than 0.5 mg/L.At the same time,the plants can grow normally under 10 mg/L of Zn2+ or Pb2+ treatment,which provided effective basis for aquatic plant in the metal threshold for ecological repair.