| Oil-Tea belongs to Camellial.L.of Theaceae which is a unique and important edible woody oil plant in southern China .It is one of the four famous oil plants in the world. In this paper, by simulating different concentrations of acid rain on the three varieties (number1,number2,number3) of Camellia oleifera seed to sprout in response to experimental stress。The results showed that :There is a certain degree of inhibitionon for seed germination by simulated acid rain pH3.5 Camellia stress。The content of MDA increase with decreassing of the pH value Of acid rain,showed negative correlation,and correlation coefficient R <-0.96**;But the content of POD reduce with the reduction of the pH value Of acid rain,showed positive correlation, and correlation coefficient R>0.94*;The number 1 and number 3 performance to the changes that the content of POD increasing at first and reducing at last with the stress time of acid rain increasing. The number 2 performance to the changes that the content of POD increasing with the stress time of acid rain increasing.In this paper, by simulating different concentrations of acid rain on No. 1,2,3 Camellia varieties for seedling growth in response to experimental stress. Discussing from the physiological and ecological aspects of Camellia seedling growth in response to the situation,the main results of the following :①Through a comprehensive analysis of experimental data by DPS can be drawn that the pH value of less than 4.5 of simulated acid rain significantly lower the content of chlorophyll a,chlorophyll b,total chlorophyll and the ratio of chlorophyll a and chlorophyll b.Show that the pH value of acid rain reduced the inhibition of chlorophyll synthesis,accelerated the decomposition of chlorophyll,declined the ratio of chlorophyll a and chlorophyll b,reveal that synthesis mechanism of photosynthetic pigments in leaves have been damaged.②Over a period of time after the stress of different concentrations simulated acid rain,with the decrease of pH value of simulated acid rain,the content of Proline and MDA increased remarkably, showed negative correlation,and correlation coefficient respectively were R <-0.9**,R<-0.93**. There is a significant difference between the CK treatment and the each of treatment which the pH less than 5.5 on the content of MDA.And there are some significant differences between the contrast (CK) treatment and the each of treatment which the pH less than 4.5 on the content of MDA and proline. In addition,the content of proline increased with acid rain stress time, and the content of MDA first increased and then decreased which in the leaves of each different variety treatment. ③The activity of SOD in Camellia oleifera Abel Seedling leaves are decreased significantly with the the pH value decreased,the correlation coefficient more than 0.918(R>0.918**).There are to achieve a significant difference level between contrast treatment (CK) and the PH value less than 5.5 of each treatment on the SOD activity.It showes that the SOD activity of Leaves was significantly inhibited after enhancing concentration of acid rain. Under the conditions of this experiment ,with the stress time continue, the SOD activity occurred changes that first declined and then rised,finally decreased in Camellia seedlings.④After a certain period of time of Acid rain stress, K+, Mg2+, Ca2+ exudation volume of Camellia seedling leaves reducted with the increase of the PH value, showed a certain negative effect, the correlation coefficient R <-0.91 **. There are significant differences between contrast treatment (CK) and the PH value less than 4.5 of each treatment on the K+,Mg2+,Ca2+ exudation volume.⑤There are positive correlations among total chlorophyll,chlorophyll a / b and SOD that they showed respectively negative correlation with the content of MDA,proline,Ca2+,Mg2+,K+.And there are positive correlations among the content of MDA,proline,Ca2+,Mg2+ and K+.⑥After the stress of acid rain for a certain period of time, net photosynthetic rate (Pn), transpiration rate (E)and stomatal conductance (Gs) first rised and then declined with the reduction of pH value in varieties of Camellia seedling.The leaf net photosynthetic rate (Pn) achieve maximum under pH4.5,and reach the minimum value under PH2.5. There is a significant positive correlation among them. The leaf intercellular carbon dioxide (Ci) concentration showed a negative correlation effect with the stomatal limitation value (Ls) and leaf water use efficiency (WUE) in varieties of Camellia oleifera seedling which don't show significant changes with the pH value of acid rain,and this effect is significant.The leaf stomatal limitation value (Ls) and leaf water use efficiency (WUE) showed positive correlation which reaches extremely significant level .After the disposa of acid rain under pH 2.5,the reduction of Gs associated with increasing of Ci, at the same time Ls is reducing which in The process of reducing on Pn,which belongs to the type of non-stomatal limitation.⑦The largest photochemical efficiency,the potential activity of PSⅡand actual photochemical efficiency of Camellia oleifera seedling leaves have markedly declined under pH2.5 .The largest quantum yield of photochemistry (Fv / Fm) declined with the the reduction of PH value that shown a downward trend,the positive correlation coefficient more than 0.83( R> 0.83).The potential activity of PSⅡ(Fv / Fo) of Camellia oleifera seedling declined with the reduction of PH value,the positive correlation coefficient more than 0.993(R≥0.993 **).The value of actual photochemical efficiency of leaves decreased with the reduction of PH value, the positive correlation coefficient more than 0.73( R> 0.73). That present a positive correlation Among them more or less.⑧To some extent,Camellia seedling growth was inhibited by the stress of acid rain. Tree height and diameter showed a decreasing change with the reduction of the PH value .They present a positive correlation,and the correlation was significant. The injury on the leaves of Camellia varieties seedling was very obvious under pH2.5 compared with other treatment,but the victimization rate is not very high.
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