Studies On Growth And Resistance Of Festuca Arundinacea Under The Stress Of Cd²⁺ And Cd²⁺-Zn²⁺

Festuca arundinacea Schreb attributes to Festuca , Gramineae, it is typical of anti-decease, cold-resisted and drought-resisted. In this paper,we adopt potted plant Festuca arundinacea Schreb to study the effect of growth and resistance under different concentrations of Cadmium and Zinc and the compound of Cadmium and Zinc stress, and investigate how Festuca arundinacea Schreb bear the pollution of Cadmium and Zinc and the interaction between Cadmium and Zinc. The main conclusions are as follows:1. The seed germination is promoted under the low concentrations of Zn²⁺, and the seed germination is inhibited under the Cd²⁺ stress. The root and plant length decreases with the increasing concentration of Cd²⁺ and Zn²⁺. Zn²⁺and Cd²⁺ stress has more significant inhibition effects on root than on the seedling, and the relationship between inhibition rate of root elongation and Zn²⁺ and Cd²⁺ concentration is astounding.The Intervene Concentration 50 of Festuca arundinacea Schreb under the Zn²⁺ and Cd²⁺ stress is 58.12mg·L^-1 and 3.94mg·L^-1 respectively. Toxicity of root is heavier than seedling.2. Growth increases when the concentration of Zn²⁺ is 600mg·kg^-1, and plant height and biomass are more than the control. With the increase of the concentration of Cd²⁺ ,the more toxical effect of the growth, this effect can be typical of the low height of plant, the low content of chlorophyll and the increase of the content of MDA. This paper shows that when the concentration of Cd²⁺ is lower than 10 mg·kg^-1 and more than 1 mg·kg^-1, certain concentration of Zn²⁺ can alleviate the damage brought by Cd²⁺. The content of chlorophyll under the compounds of Zn²⁺ and Cd²⁺ is lower than that of control. MDA content increased according to the increasing of concentration, and the protein content decreases under the high concentration of Cd²⁺ and Zn²⁺ stress.3. Single concentration of Cd²⁺ and Zn²⁺ has great effects on the activity of SOD,POD and CAT, the accelerated and inhibited effects are dependant on the sort and concentration of heavy metals. Under certain concentrations of Cd²⁺ and Zn²⁺, the activity of SOD,POD and CAT increases, but when the concentration is high, some activity decreases.The compounds pollution of Zn²⁺and Cd²⁺ has complex effect on anti-enzyme system, and this pollution relates to the different combination between Zn²⁺and Cd²⁺. SOD,POD and CAT activity have difference bewteen leaf and root.