| Trace elements Zinc (Zn), as the one essential nutrient for human growth and development. Zn deficiency can cause growth retardation of children, mental retardation, decreased immune function and other physical diseases. Since Zn can not be synthesized in the human body, supplemented by the outside world is the only means to make more drugs more safely and effectively in terms of food supplement. In fact, the human body is basically the amount of the required Zn from the food. The difference Zn content in the food is due to the different types of food and variety, and the availability of Zn in soil caused by the difference. The global arable land lack Zn up to 30%. In our country more than 40% arable lands have the Zn deficiency problem. Simple application of Zn fertilizer through the soil to change the soil Zn content of plants and thus affect the absorption of Zn element approach, which will face the enormous economic costs, particularly for developing countries will be hard to be implemented effectively. Therefore, in agricultural production, how to increase the crops uptake Zn and increase crop Zn enrichment of the amount of edible parts on the basis existing resources of Zn. With the development of technology, the 90's, use genetic improvement to make the crops enrichment Zn and use breeding work to get high enrichment Zn crops have gradually expanded and made some considerable progress. But more concentrated on such as rice, wheat, and corn what both are the global food crops As the world oilseed rape, in daily life play a vital role, especially for our people is concerned, there is less to be reported. To better understand the different rape cultivars with different Zn concentrations will have what differences in in the enrichment of Zn and mechanism. this study used self-made root bag method of soil culture experiment, in the neutral purple soil of 5 rapeseed varieties (Brassica)after the application of different concentrations of Zn, Zn accumulation differences, while of different Zn on rape biomass, physiological and biochemicalindicators, root exudates, root tip cells, plant N, P, K and Zn content, soil N, P, K and Zn content to the mechanism for the rape of Zn-rich to provide a theoretical basis.1. Different Zn concentrations on the growth of different varieties of different rape. With increasing concentrations of Zn. rape plant height, root length, aboveground and underground dry weight will have the parabolic trend that at first high and then decreased. Zn concentrations were reflected in the 5.0mg/kg maximum time value. But when the Zn concentration of 20.0mg/kg, Nantong yellow rape and H33 grow better than others.In 5 rape varieties. Erniuwei and Liyangkucai the two species in biomass is better than the other species. 2. With the increasing concentration of Zn 5 rape varieties SOD, CAT and POD activity showed three general tend to drop and then increasing, and the difference between treatments is significant. In the Zn concentration of 5.0mg/kg, each rape cultivars were the lowest of three antioxidant enzymes, with the Zn concentration (≥10.0 mg/kg) increased the enzyme activity continued to show increasing trends. In 5 rape varieties, the two species of Erniuwei and Liyangkucai have the lowest of three antioxidant enzymes. plant growth is better than the other varieties of rape the state. The MDA and Pro in the rape leaves with different Zn concentrations change have the trend which first decreased and then increased, in the 5.0mg/kg the value will down the lowest. In 5 rape varieties, the two species of Erniuwei's and Liyangkucai's MDA and Pro lower than the other species. Show that the two varieties of Zn strong adaptability and resistance.3. Rape chlorophyll a, b and total chlorophyll content increased with the Zn concentration showed a parabolic trend, was first increased and then decreased, and the maximum Zn concentration in the 5.0 mg/kg appeared in, and the differences in chlorophyll content between the different treatments significantly, but Differences among varieties were not significant. Rape plant net photosynthetic rate, transpiration rate and stoma conductance that with the Zn concentration increase which the trend from low to high last to low. When the Zn concentration of 5.0mg/kg, Pn, Tr, Gs high content than other treatments. Intercellular CO2 concentration in the body of rape, it have a opposite trend which compare with the Pn, Tr and Gs. In 5 rape varieties, the two species of Erniuwei and Liyangkucai's Ci content in the 5.0mg/kg will get the lowest. It shows that this 2 species have stronger photosynthetic ability in the other rape varieties.4. To follow in high Zn concentrations (20.0mg/kg) the rape root produced more exudates to respond to environmental stress.5 rape varieties will get 14 amino in the rhizosphere, content in the 0.012～1.783mg/100ml. The main amino acid have gultamic, methionine, leucine, phenylalanin and lysineln 5 rape varieties, the two species of Erniuwei and Liyangkucai's amino higher than the other species, Showed that Zn concentrations of different varieties of rape of different cell membrane permeability. Root tip----as a life activities zone, its cell structure with different concentrations of Zn treatment showed significant differences and significant differences among varieties, compare with CK high concentration (20.0 mg/kg), in rhizosphere cell the mitochondria and vacuoles have most obvious changes, there's swelling of mitochondria and vacuoles of the aggregation. H33 species's root tip cells ultrastructure was not significant compared with the CK, which may be stronger Zn-resistant variety H33 physiological mechanisms.5. In different Zn concentrations, five rape varieties in various parts of N, P, K nutrient uptake and transport differences obvious. Bloom stage nutrient content was lower than maturity stage. grain and leaf nutrient content was significantly higher than in roots and stems. This shows that plants nutrient transfer from the ground to shoot. Shift from vegetative growth to reproductive growth area sites. In 5 rape varieties, the two species of Erniuwei and Liyangkucai's nutrient content is the highest, indicating that the two will be more effective nutrient supply in the shoot and meet the reproductive organs to ensure normal growth and development, to provide guarantees for the grain filling.6. Zn concentrations of different treatments on the soil rhizosphere and non-rhizosphere in nitrogen, phosphorus and potassium effects are different. In rhozosphere soil, with Zn concentration increased the nutrient content will first decrease then increasw,5.0mg/kg the nutrient will get lowest value. In 5 rape varieties, the two species of Erniuwei and Liyangkucai's nutrient will get lowest value in the 5.0mg/kg concentration. That indicating this 2 species of plant nutrients higher than the other plant growth during the growing demand.7. In different part of the plant body, with Zn concentration change to different the rape's Zn content and enrichment contents both significant differences. Especially in the part of rapeseed which Zn content more obvious. The rape roots, stems, leaves and seeds parts are will show higher with the Zn concentration change. That show in the growth process of Zn will transfer from the ground to continue to shoot, and also from vegetative growth to reproductive growth. In the 5 rape varieties, the two species of Erniuwei and Liyangkucai's Zn contents are the highest than the others, show that this 2 species have more ability of absorption for Zn. About the different rape species have the Zn enrichment ability. In 5.0mg/kg Zn concentration, Erniuwei and Liyangkucai have the most enrichment contents. That indicating this 2 rape species the ability to enrich Zn are the best when the Zn concentration in 5.0mg/kg.
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