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In this study, two tea varieties of the Mingshanbaihao and Pingyang extremely early study using orthogonal experiment method pot experiment, soil application of different concentrations of Cr (NO3) 3.9 H2O, As2O3, Cd (NO3) 2.4 H2O, Pb (CH3COO) 2.3 H2O, a system of Cr, As, Cd, Pb combined pollution on physiological characteristics of tea. The results show that: (1) Cr, As, Cd, Pb combined pollution impact on the amount of tea tree spring shoots growth combined pollution of two tea varieties of spring shoots two leaves and a bud length and weight are obvious. Compare spring shoots length, two varieties in addition to treatment 1 and treatment 2 and 4 the length of the spring shoots higher than that of the control, the remaining processing were lower than the control. The spring shoots weight, in addition to dealing with a higher than that of the control, the remaining processing are lower than that of the control. This spring shoots growth of two varieties of the tea plant are subject to composite pollution inhibition, the degree of inhibition of Mingshanbaihao strong in Pingyang extremely early, extend the time with the pollution, the the tea tree victimization severity. (2) Cr, As, Cd, Pb compound contamination on photosynthesis physiological impact in this experiment, the tested varieties of chlorophyll a and b content and total chlorophyll significantly lower than the control. Range analysis can be seen, the composite impact of pollution on the Mingshanbaihao chlorophyll a, b content and total chlorophyll same trend, with Cr, As, Cd, Pb concentrations increase and reduce, Cr, As the three indicators the greatest impact; extremely early for Pingyang Cr chlorophyll a and total for the first increases and then lower the maximum 100mg/kg concentrations, indicating that the soil add a concentration of 50,100 mg / kg of the outer source Cr chlorophyll a and total stimulus effect, As, Cd, Pb both influence is declining. The two cultivars tested chlorophyll synthesis overall by the degree of inhibition, and the degree of suppression Mingshanbaihao strong in Pingyang extremely early. Compared with the control, the two tested cultivars net photosynthetic rate (Pn), stomatal conductance degrees (Gs), intercellular CO2 concentration (Ci), transpiration rate (Tr) are reduced, that the combined pollution 2 The varieties tested photosynthesis has also been suppressed. Range analysis, the Cr 2 Leaf Ci, Gs, Tr affect most obvious As Pingyang special early Pn impact Pb Mingshanbaihao Pn. Analysis of variance showed that soil to add Cr and As of Pingyang special early blade Pn, Gs, Ci, Tr influence are extremely significant, Pingyang extremely early leaves of Cr and As pollution is the most sensitive. Of soil Cr of the Mingshanbaihao blade Ci, Pn, Gs, Tr affect were significantly; the Mingshanbaihao Cr contamination is the most sensitive, As contamination is relatively weak. (3) Cr, As, Cd, Pb compound pollution on tea plant resistance physiology combined pollution two tested varieties SOD, POD, CAT activity, proline, malondialdehyde (MDA), the relative conductivity of content showed a increasing trend in each treatment were significantly higher than the control. The three kinds of activity increase of Cr, As, Cd, Pb compound pollution in the experimental concentration range, tea has tolerated; proline, malondialdehyde stress resistance index increase, indicating the tea antioxidant enzyme activity increase under the combined pollution and can not avoid membrane lipid peroxidation in the occurrence of composite pollution has had a toxic effect on the tea leaves. The range analysis show that Cr of Pingyang extremely early SOD, POD, CAT activity, proline, the relative conductivity of the content of the greatest impact, As malondialdehyde; the purpose of Mingshanbaihao, Cr of more than six indicators the impact. The analysis of variance showed that the soil two tea varieties above six indicators were significantly adding exogenous Cr. Multiple regression analysis showed that the kinds of elements Cr, As, Cd, Pb4 early Pingyang special SOD, POD, CAT activity, proline, malondialdehyde content, relative conductivity showed synergistic activity and proline malondialdehyde synthesis is mainly affected by the impact of Cr, As. For Mingshanbaihao four elements of SOD, POD activity and proline, malondialdehyde content, relative conductivity showed synergistic elements Cr, As, Pb CAT activity showed a synergistic effect, Cd its showed antagonism the synthesis activity Mingshanbaihao is mainly influenced by Cr impact, proline, MDA content, relative conductivity of synthetic Cr and As. The gt; concentration sequence for Pb Cr, As, Pb, Cd added of Cr gt; of As gt; Cd. Highest concentration of Pb, but the tea physiological characteristics of the relatively minimal; As the concentration is low, but it is a key factor to affect the physiological characteristics; the Cd concentration much higher than the soil environmental quality standards in the soil threshold, but tea tree physiological characteristics of relatively small. These results indicate that, Cr, As, Pb, Cd, In addition to the elements by add tea, but also by the co-existence of elements, and its impact is more complex, depending on the combination of the concentration of the element at a certain point, coexisting elements most antagonistic or synergistic effects. Therefore, the combined pollution on physiological characteristics of tea is a combined effect. Different varieties due to differences in genetic characteristics, the composite pollution physiological response in common, there are differences. The experimental results show that, Is Pingyang special earlier Pekoe composite pollution tolerance stronger than mountains.
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