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Phytoremediation of Zn, Cu pollution is one direction of today's environment and biology research. Currently screening of plant species for phytoremediation is mainly concentrated in the hyperaccumulators. Hyperaccumulators has strong enrichment capacity, but there are a small amount of biological growth areas and constrained environment, species with fewer resources and other unfavorable factors, thus limiting the application of this green biotechnology. This topic intends to use the woody plant poplar as an alternative plant for phytoremediation, test simulation Zn, Cu stress environment, research poplar on Zn, Cu stress physiological response and enriched the distribution of in vivo Zn, Cu, law to explore the resistance and restoration of the potential difference between the different poplar materials for the use of poplar phytoremediation provide some theoretical preparation. In this study, Huazhong Agricultural University, 5 poplar material base cuttings as test materials (I-69 South anti evergreen Yang, the lobular Yang and Lushan Yang), using different concentrations of Zn, Cu carry out treatment, research Zn, Cu poplar materials plant growth, leaf relative conductivity, chlorophyll content, soluble protein content and malondialdehyde (MDA), the impact analysis of Zn, Cu 5 poplar material in vivo distribution, accumulation and migration characteristics, planting poplar material, soil, Zn, Cu content and the pH value changes, and the poplar accumulation of Zn, Cu and Toxicity physiological mechanisms discussed. The following main results: (1) from the apparent form, of 5 Poplar materials of Zn, Cu stress resistance were lobular Young> the Lushan Young> South anti-2> 1-69> evergreen Yang. (2) 5 poplar material of height and diameter growth rate decreased significantly with Zn, Cu stress increases. Considering the changes in growth indicators, the five poplar material growth on Zn, Cu stress resistance were Lushan Yang,> Nankang 2,> 1-69 Young> the evergreen Young> lobular Yang. (3) with Zn concentration increases, the biomass of poplar materials exist increasing trend after the first drop, with the Cu concentration increased, poplar biomass downward trend, Zn, Cu interaction stress conditions, poplar The biomass decrease the rate gradually decreasing trend with the increase in the concentration of both interaction, moderate concentrations of Zn, Cu interactions promote the accumulation of poplar biomass. (4) with Zn, Cu concentration, of 5 Poplar materials chlorophyll relative content was significantly reduced. Among them, the lobular Yang by stress, leaf relative chlorophyll content is still the highest, and the content faster recovery. (5) with Zn, Cu processing time, the poplar leaf relative conductivity increases gradually. Significant difference among the materials, lobular Yang and South anti-2 cell membrane by the lowest degree of injury. Poplar leaf relative conductivity increased rate with Zn, Cu interaction concentration increase gradually decreasing trend, the high concentration of Zn, Cu mutual constraints on poplar cell membrane destruction. (6) Zn, Cu treatment after 21 d, the size of the content of soluble protein in the leaves of poplar material: lobular Yang evergreen Young> the Lushan Young> South anti-2 I-69 Young. The soluble protein content of Cu ion concentration increased first and then decreased trend, with increased Zn ion concentration down then up, and reached the highest value in the 600 mg / g. (7) poplar leaves MDA content with the treatment time gradually increases. Significant difference between the respective materials. Overall, the MDA content in the leaves of poplar with Zn ion concentration on the rise, with the concentration of Cu ions is presented first and then decreased. Zn, Cu interaction, MDA content in the leaves of poplar with Zn, Cu interact with the increasing concentration of reducing, with Zn, Cu interaction concentration, poplar leaf membrane increase in the level of damage. (8) different poplar material on Zn, Cu enrichment capabilities exist between species, the lobular Yang body Zn, Cu accumulation of the most strongest enrichment capacity and lobular Yang Zn accumulated in the root, and mainly of Cu accumulated in the stem; 5 poplar absorbed by the material Zn accumulation in various organs of root> leaf> stem; Cu accumulation in various organs of root> stem> leaf. (9) different concentrations of Zn processing of Zn, Cu migration coefficient in various parts of the poplar had no significant effect, different concentrations of Cu reached a significant level only on the amount of Cu accumulation in the root, the poplar roots of accumulated Cu content with the deal with the increase of Cu concentration increases. Overall, poplar Zn, Cu stress has a strong endurance, low concentrations of Zn on Growth had no influence, and high concentrations of Zn, Cu on Growth produce toxic effects, and with the stress concentration improve the treatment time and increase the level of poison. Zn, Cu stress, five poplar material on Zn, Cu of resistance Sort: the lobular Young> South anti evergreen Yang> I-69 Yang Lushan Yang and five poplar material Consolidated Inter the resistance significantly different. 5 poplar material alone on Zn, Cu's sort of resistance are: the lobular Yang> South anti-2 I-69 Young evergreen Yang Lushan Yang.
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