| Cd (Cadmium) is a highly toxic, migration, easy accumulation of heavy metals. In recent years, due to environmental pollution, pesticides,fertilizers and other chemical products as well as the long-term heavy use of inappropriate management (such as sewage irrigation, sludge and slag soil improvement, organic fertilizers containing Cd, etc.), a lot of agricultural land has been subject to varying levels cadmium pollution, including vegetables and orchards are more serious.Cadmium contamination of soil can lead to reduced plant respiration, chlorophyll synthesis blocked, reduced photosynthesis, nucleic acid and protein synthesis blocked, inhibited stomatal opening of water metabolism, interfere with leaf nitrogen metabolism, disrupting nutrient absorption balance, resulting in confusion in plant metabolism, nutrient disorders, blocked normal growth and development of plants and cause reduced quality of agricultural products, cut production or even crops, to farmers have serious mental and economic losses. More importantly, cadmium can enter the food chain through plants, human and animal health threat. Human or animal, if the long-term ingestion of contaminated plants or agricultural products, cadmium can accumulate in humans and animals, and thus lead to osteoporosis, bone disease, kidney damage and a series of illnesses, and is extremely carcinogenic, teratogenic effects.Chardonnay grapevine (Vitis viniferaa)originating from Burgundy, the world's most popular wine grape, is early maturing varieties. As for all types of weather, cold, high output and stable, easy to grow, it can almost be grown in all wine regions of the world. With the wine-industry booming in China, Chardonnay as one of main cultivated varieties of grapewine, face against a wide range of pests and diseases and natural disasters (freezing, drought and flood) threats, in order to improve the quality of Chardonnay grapes, production of high quality wine, rootstocks has become a hot topic. Based on the above understanding,The young plants self-rooted and grafted on rootstock 5BB/SO4 were used as material to study the effects of cadmium in Chardonnay grapevine (Vitis vinifera). The toxic response mechanism of cadmium on the self-rooted and grafted seedlings to cadmium stess were studied by add to cadmium and inhibitors.We also explored calcium chloride on the inhibitory effect of toxicity as the theory of reference and basis of grape cultivation and production of pollution-free scientific.In this experiment, a mixture of CdCl2·2H2O+1/2 Hoagland were poured into roots to study cadmium accumulation and physiological effects and distribution of its shape in Chardonnay.The main results were as follows:①High concentration of cadmium (3mmol/L) inhibited the germination, node elongation and thicker, shoot elongation, and reduced the blade area,significantly reduced the growth rate of shoots.②Within the range of 0～mmol·L-1, Effects of different concentrations of cadmium on antioxidant enzyme activities in young plants is different.Low-cadmium (0.5,1 mmol/L) can stimulate the expression of enzymes to improve the activity and root activity, increased soluble protein contents and oxygen radical production rate and reduced the MDA contents. high cadmium (4mmol/L) inhibited the play. Activity decreased, soluble protein and free radical production rate decreased, MDA content increased, causing a large number of plants, the accumulation of ROS, causing oxidative damage.③Under the 1mmol/L Cd stress, the activities of antioxidant enzymes and the relative conductivity increased first and then decreased with the treatment time.Three days later treated by cadmium, SOD and POD, activities increased significantly, is the main enzymes scavenging reactive oxygen species,while CAT and APX activity began to increase in 7d after treatment,, that is to help remove the lots of ROS.④The compartment and accumulation of cadmium in root, stem,shoot and leaf were significantly different. The accumulation rule was:root> stem> petiole> leaves> shoots. Contents of cadmium in roots and stems take above 90% of the whole plants. This reflects the roots played a strong rejection role of cadmium. Subcellular distribution of cadmium contents is cell wall>soluble Section>organelles either in roots or leaves. Accumulated in the cell wall more than 50% of cadmium, probably is one of the cadmium tolerance mechanisms of chardonnay plants.⑤The extractable Cd exists mainly sodium chloride in the Chardonnay seedling roots, followed by acetic acid extraction of state, then, hydrochloric acid and ethanol extractable, deionized water extractable at least. As the concentration increased, the extraction changes in different states, including sodium chloride and acetic acid extractable upward trend.⑥Contents of nitrate and ammonia nitrogen was significantly decreased in roots,while t increased sharply in leaves under the cadmium stress.It's possibly to reduce nitrate and ammonium absorption because of root activity and cadmium nitrate reductase activity reduced, interference with nitrogen metabolism, nitrogen assimilation caused to stop, resulting ammonium toxicity for a large number of leaves of ammonium accumulation.⑦Exogenous calcium can inhibit the absorption and transportation of cadmium.It cannot only increase sodium chloride extractable contents in roots, and promote root activity and the expression of protective enzymes, but also increased soluble protein content, decreased MDA contents.Compared to 10mmol/L, Adding 5mmol/L CaCl2 played a significant and better toxic effects of mitigation.
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