Study On Physiology And Identification Index Of Cold Resistance Of Zenia Insignis Chun

Seedlings and one-year dortmant shoots of 6 provenances of Z. insignis were taken as materials in this study, that is:Tongdao, Xingyi, Xincheng, Jjianghua, Jingxi and.Yingde.9 physiological and biochemical indexes that relative to resistence were studied after low tempreture treatment, then used SPSS to do the data processing, correlation analysis, main component analysis and regression analysis included. Results are as follows:1. During the low-temperature inducement, the contents of soluble protein and soluble carbohydrate, the SOD enzyme activity presented a correlation positively with cold resistance of Z. insignis at 0.01 level, the increase of proline contents and POD enzyme activity correlated positively with cold resistance of Z. insignis at 0.05 level, respectively, the contents of MDA correlated negatively with that at 0.01 level. The results showed that the content of soluble protein, soluble carbohydrate, MDA and the activity of SOD enzyme could be taken as main factors to identify the cold resistence of Z. insignis seedings;2. When the tempreture fell to 7℃, the contents of soluble protein, soluble carbohydrate and proline came to maximum, the same as the activity SOD and POD enzyme; At the same time, the contents of MDA came to minimum. It indicated that the Z. insignis had the maximal cold resistance at 7℃;3. The results of PAGE of soluble protein indicated that 5 bands might have correlation to plant cold resistance,'two of which appeared after low-temperature inducement and the rest showed the increase of soluble protein;4. The equation measuring cold resistance was founded:Y=-5.433+0.270X1+0.328X2+0.004X4-1.383X9 (X1, X2, X4, X9 represent respectively:soluble proteins content, soluble carbohydrates content, SOD enzyme activity and MDA content);5. The electric conductivity of the one-year shoots of 6 Z. insignis provenances were increased with the temperature decrease, and showed a significant difference at -12℃. When put the relative electric conductivity in different temperature treatments into Logistic equation, the semi-lethal temperature of the 6 provenances can be calculated, as follows:Tongdao-13.06℃, Xingyi -12.07℃, Xincheng -11.29℃, Jianghua-10.22℃, Jingxi-10.76℃, Yingde -11.74℃;6. The results of cluster analysis showed that the 6 tested provenances could be divided into 3 groups according to their index character, as follows: strong cold resistance, moderate cold resistance, weak cold resistance. Tongdao belonged to the strong group; Xingyi, Xincheng and Yingde belonged to the moderate group; Jianghua and Jingxi belonged to the weak group;7. The sequence of cold resistance of 6 provenances was:Tongdao> Xingyi>Yingde>Xincheng>Jianghua> Jingxi.