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The development of modern industry and agriculture, resulting in heavy metal pollution is worsening. This article nurture and peanut callus dense water as the experimental material, Zn2 heavy metals and Ass stress factors, to explore the mechanism of heavy metal stress on aquatic plants. The results show that: (1) with 70% alcohol sterilization 30s, and then with 2% sodium hypochlorite sterilization 15min and finally to 0.1% mercuric sterilization 5min can kill most microorganisms, sterile culture for water peanut better sterilization. Selection of stem segments with axillary buds as explants and inoculated in 1/2MS be 6-BA (2.5mg / L) / NAA (0.1mg / L) medium, the highest rate of callus induction. Stress (2) different Zn2 concentration (0,10,50,100,200 mg / L), low concentrations of Zn2 (10 mg / L) of water peanut callus not hurt so much when Zn2 ??concentration lt; 50 mg / L when plant callus cells of superoxide dismutase, peroxidase and hydrogen peroxide activity of soluble protein, free proline, GSH and AsA contents were increased. With Zn2 concentration can cause chlorophyll a, chlorophyll b decreased soluble protein content decreased, proline, glutathione and ascorbic acid content decreased; water peanut callus ROS scavenging system, SOD, POD CAT three enzymes balance is destroyed, can not effectively prevent the accumulation of 02 - and H202, higher content of free proline accumulation MDA content height. The scanning electron microscope findings ZN2 destruction of the membrane systems of the cell, particularly chloroplasts, mitochondria, endoplasmic reticulum, nucleus caused irreversible damage. Zn2 broke the physiological and structural basis of water peanut callus required for normal metabolism, disrupted metabolic balance, resulting in the death of callus. However, changes in the structure to lag behind the physiological changes. Zn2 water peanut callus lethal concentration range 50-200mg / L. (3) Ass concentration (0,5,10,25,50 mg / L) under duress, water peanut callus chlorophyll a, chlorophyll b and soluble protein content declining, malondialdehyde (MDA) and free proline rise; peroxidase and catalase activity first increased and then decreased the superoxide activity sexual activity downward trend, glutathione and ascorbic acid content first and then decreased, but higher than the control value. The As5 water peanut callus lethal concentration in the range of 10-50mg / L. In summary, the toxic effects of heavy metals on the water peanut callus poisoned with heavy metals on aquatic plants physiological and structural changes are basically the same, that is, the amount of heavy metals pollution on plant callus growth did not significantly affect With the increase of the concentration of the toxic effects become more apparent. By poisoning resulting from the processing of callus conclusion has practical value, can be applied to aquatic plants for water pollution governance research which has the advantage of not external factors and mass production and callus , which is of great significance to improve efficiency and cost savings in the course of the study.
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