Seed Germination And Seedling Growth Of Triticum Arstivum Under The Stress Of Cu And Pb

In rencent years, the environmental pollution caused by heavy metal has brought extensive attention. Heavy metal had effect on the growth and the physiological activity of crops when in soil. Therefore, the research of crops growth and the physiological changes under heavy metal stress has profound effect. This paper studied the germination,growth and antioxidant effects of Triticum arstivum under different concentration of single Cd and Cu and Cd-Pb compounds, The results were as follows :1.Low concentration Cu,Pb and Cd-Cu compounds had little effect on the germination of Triticum arstivum. 1.6 mg·L^-1Cu promoted germination rate, and significantly increased the seedling height and root length. The germination rate, germination index, energy index, height and root length decreased gradually and the seedling growth was seriously inhibited along with the increasing concentration of single Cu and Pb and Cu-Pb compounds.The inhibition on root of Cu, Pb and Cu-Pb compounds was bigger than bud.The poisoning effect of Cu-Pb compounds on seed germination was bigger than on single Cu and Pb stress.2.50 mg·kg^-1 Cu stress promoted the growth of Triticum arstivum slightly, seedling height, root length and biomass increased campared with the control, but the difference was not significant. In low concentrations of Pb and Cu-Pb compounds stress, the growth of Triticum arstivum has been inhibited. With the increasing concentration of single Cu,Pb and Cu-Pb compounds,the growth of Triticum arstivum has been inhibited severely. The effect of Cu-Pb compounds on the growth of Triticum arstivum was bigger than single Cu and Pb stress.3. 50 mg·kg^-1Cu stress increased the chlorophyll content of Triticum arstivum. In addition, with the increasing concentration of single Cu,Pb and Cu-Pb compounds, the chlorophyll concent was gradually declined. Cu-Pb compounds had the largest effect on chlorophyll content. MDA and praline concent gradually increased with the increasing concentration of single Cu and Pb, and had positive correlation with Cu and Pb concentration. Cu, Pb and Cu-Pb compounds stress have obviously affected SOD, POD and CAT activity. Under single Cu and Pb treatment, SOD activity rised and then declind, along with the increasing concentration, POD and CAT activity rised in general. When SOD activity was inhibited, POD and CAT activity were still be activated. POD activity was reduced under high concentration of Cu-Pb compound .Single Cu and Pb and Cu-Pb compounds had little effect on CAT activity.