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Cd (Cadmium) is a highly toxic, mobility, easy accumulation of heavy metals. In recent years, due to environmental pollution, pesticides and fertilizers and other chemical products as well as long-term heavy use of inappropriate management practices (such as irrigation, sludge and slag soil improvement, organic fertilizers containing Cd, etc.), a lot of agricultural land have been affected to varying degrees cadmium pollution, in which land and orchard land vegetables more serious. Soil cadmium pollution can lead to reduced plant respiration, chlorophyll synthesis is blocked, reduced photosynthesis, nucleic acid and protein synthesis is blocked, inhibition of stomatal opening, affecting water metabolism, interfere with leaf nitrogen metabolism, disrupt the balance of nutrient absorption, causing confusion in plant metabolism, nutrient disorders, normal plant growth is retarded, thus resulting in decreased quality of agricultural products, cut or even crops to farmers bring severe mental and economic losses. More importantly, cadmium can enter the food chain through the plant, human and animal health threat. Human or animal prolonged 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 has a strong carcinogenic, teratogenic effects. Chardonnay (Chardonnay transliteration, also translated: Chardonnay) originating from Burgundy, is currently the world's most popular wine grapes, an early maturing variety. As for a variety of types of weather, cold-resistant, high yield and stable, easy to grow, almost all wine producing regions in the world widely planted. As the wine industry to flourish in our country, as China cultivars Chardonnay wine varieties, faced with a wide variety of pests and diseases and natural disasters infringement (frost, drought) threat, in order to improve the quality of Chardonnay grapes, production quality wines, grape cultivation resistant rootstocks also become a research hotspot. Based on the above understanding, the subject of the use of Chardonnay (Chardonnay) self-rooted and grafted seedlings as test materials, by adding exogenous cadmium and cadmium uptake inhibitors to explore the mechanism of cadmium poisoning of grape and self-rooted and grafted seedlings to cadmium response, and calcium chloride on the toxicity of cadmium chloride absorption and relieve the inhibition effect of scientific cultivation of grapes and production of pollution-free products to provide reference and theoretical basis. In this experiment, self-rooted Chardonnay, Chardonnay anvil S04, Chardonnay rootstock 5BB as test materials, the use of CdCl2 · H2O 1/2Hoagland poured roots approach to study cadmium on Chardonnay and seedling physiological effects accumulation and distribution patterns. The results showed that: ① high concentrations of cadmium (3mmol / L) can inhibit the germination of seedlings Chardonnay, internode elongation and thicker, shoot elongation, reduced leaf area, significantly reducing the growth rate of new shoots. ② different concentrations of Cd on Chardonnay seedling antioxidant enzyme activities were different. Cadmium (0.5,1 mmol / L) can stimulate the expression of enzymes to improve the activity and root activity, increased soluble protein content and oxygen radical production rate, decreased MDA content, high cadmium (4mmol / L) will play an inhibitory effect. Activity decreased, soluble protein and free radical production rate decreased, MDA content increased, causing massive accumulation of ROS in plants, causing oxidative damage. ① 1mmol / L cadmium stress, with the treatment time, Chardonnay seedlings protective enzyme activities and relative conductivity increased first and then decreased, while in 3d Cd stress, SOD and POD enzyme responsive, activity increased significantly , is the main oxygen scavenging enzymes, 7d after processing, CAT and APX activity began to increase, indicating that the two enzymes is to help clear. ④ Chardonnay cadmium accumulation of seedlings in the root gt; stem gt; petiole gt; blade gt; shoots. This reflects the Chardonnay strong seedling roots to cadmium interception. Cadmium Chardonnay seedling roots and leaves the subcellular distribution of cell wall gt; soluble fraction gt; organelles. More than 50% of the cell wall of cadmium accumulation, probably Chardonnay seedlings to cadmium tolerance mechanisms. ⑤ In the Chardonnay seedling roots, mainly sodium chloride extractable Cd exist. Followed by acetic acid extractable, again for the hydrochloric acid extractable, ethanol extractable, deionized water extractable content minimum. As the concentration increases, the extractable content varied from which sodium chloride and acetate extractable extractable upward trend. ⑥ cadmium chloride stress, Chardonnay seedling roots in nitrate and ammonia nitrogen content decreased significantly, leaves two forms of nitrogen content increased, possibly because of reduced root activity and cadmium nitrate reductase activity, decreased Chardonnay seedling root system to absorb nitrate and ammonium nitrogen, interfere with nitrogen metabolism, caused by inhibiting nitrogen assimilation, resulting in a large number of ammonium nitrogen in leaves accumulate, causing ammonia poisoning. ⑦ adding exogenous calcium can inhibit the absorption of cadmium and transportation, increasing NaCl roots extractable content, promote root activity and expression of protective enzymes, soluble protein content increased, decreased MDA content, has played a significant toxic effects mitigation, including Add 5mmol / L CaCl2 is better.
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