Study On Cold Resistance Of Populus Deltoids Cv.Zhonghua Hongye And Salicaceae Sp

Populus deltoids cv. Zhonghua hongye and Salicaceae sp. belong to the largesize of the tree， because of its rapid growth and excellent viewing, application themin landscape greening will have obvious effect.But in the process of introduction andCultivation indifferent regions, affected by the low temperature of environment, two kindsof plants often damage and even death phenomenon in winter.In this paper, take theannualred Populus deltoids cv. Zhonghua hongye and Salicaceae sp. as the testmaterial, they from the Baoding City of the Hebei province,studied the physiologicalcharacteristics under the different and low temperature, and by determining the relativeconductivity, MDA, solublesugar and soluble protein content, protective enzyme andcombined with the trend growth rate of recovery of shoots seven relevant experimentalindex. Study of cold resistance physiological mechanism of Populus deltoids cv.Zhonghua hongye and Salicaceae sp. comprehensive the evaluation combined withmembership function method of two kinds of plant cold resistance, through the testingindex data analysis results show that:(1)In the low temperature treatment process, gradually decreases with the temperature,the relative conductivity of the body of branches and roots from Populus deltoids cv.Zhonghua hongye and Salicaceae sp. showed gradually increased, but there weredifferences between the amplitude of variation.At-20℃, the relative electricconductivity value in the branch of Salicaceae sp. has reached more than50%, the relative electric conductivity value in branches of Populus deltoids cv.Zhonghua at-15℃has reached55.83%, and the relative electric conductivity in theroots of Populus deltoids cv. Zhonghua hongye and Salicaceae sp. reached49.83%and53.93%at-10℃.According to the test data and the Logistic equation isdetermined of four kinds of tested materials and semi lethaltemperature (LT50): semi lethal temperature in the branches and roots of Populusdeltoids cv. Zhonghua hongye are-11.46℃and-6.24℃, semi lethaltemperature in the branches and roots of Salicaceae sp. are-15.83℃and-10.07℃.(2)The measure of MDA in different and low temperature and conditions showed that: the contents of MDA in all tests of materials gradually decreases with thetemperature.The MDA in The branch of Salicaceae in the low temperature was thelowest and the smallest increased. The results of variance analysis showed that: in thetested materials, The branch of Salicaceae sp. has strong cold resistance, the root system ofPopulus deltoids cv. Zhonghua hongye has he worst cold resistance.(3)According to the analysis of the test data in the low temperature condition of artificial,the results showed that: the activity of SOD in all materials showed the downward.Trends after the first rise.The SOD activities of the branches and roots in Populus deltoidscv. Zhonghua hongye from the initial stage to-15℃increased gradually, and reachedthe peak at-15℃, SOD activity treatment decreased after low temperature;From the initialstage to-20℃，the SOD activity in the branch and root of Salicaceae sp. graduallyincreased, the rising trend is relatively slow than the branch and root of Populus deltoidscv. Zhonghua hongye. and SOD enzyme activity reached the peak at-20℃, then theenzyme activity gradually decreased.The trend of POD activity and SOD activity isbasically the same. According to the result of variance analysis showed that the significantdifference between different varieties of SOD and POD enzyme activity.(4)The soluble sugar content in different product test materials showed agradual upwardtrend after low temperature treatment, the analysis from the trend of soluble sugar contentof test materials, soluble sugar content in resistant variety was higher than that in the weakcold resistance varieties.(5)Under low temperature condition, the protein content of each test material increasedfirst and then decreased. In a certain temperature range, the increase in protein content,the branches and root of Populus deltoids cv. Zhonghua hongye reached the peak at-15℃, the protein content decreased gradually after the branches and root of Salicaceae sp.reached the peak at-20℃, the protein content decreased gradually after the tend. But thecold hardiness variety of poor its protein content was significantly less the than that ofvarieties better cold tolerance, cold resistance and plant is closely related to the proteincontent.(6)Through the relative conductivity of the branches and roots of Populus deltoidscv. Zhonghua hongye and Salicaceae sp. in the relative conductivity, SOD activity, PODactivity, MDA content, soluble sugar content and soluble protein content of6indicators.And use the fuzzy comprehensive with evaluation method of probability, sorted based onthe cold resistance of tested materials comprehensive evaluation data, its cold resistance inorder:the branches of Salicaceae sp.＞the branches of Populus deltoids cv.Zhonghuahongye＞the roots of Salicaceae sp.＞the roots of Populus deltoids cv. Zhonghuahongye（Salicaceae sp.＞Populus deltoids cv. Zhonghua hongye）.The comprehensiveevaluation result of Populus deltoids cv. Zhonghua hongye and Salicaceae sp. in coldhardiness and branches to restore growth and field performance is basically the same, by using fuzzy probability score were evaluated with the feasibility of Populus deltoidscv. Zhonghua hongye.