Studies On The Effects Of Medicament Treatment On Improving The Heat-resistance Of Primula .L

Three factors on five levels of orthogonal design experiments (temperature, medicament and consistency) were conducted to study the effects of temperature and medicament treatment on improving the heat-resistance of Primula obconica and Primula vulgaris. The main results are as follows:1. Under the stress of the different levels of high temperature, both P. obconica and P. vulgaris without SA and CaCl₂ treatments indicated that: their relative electrical conductivity and MDA content increased along with the increment of temperature. The content of free proline, soluble carbohyarate, soluble protein, chlorophyll and the activity of SOD increased at the beginning and decreased later on. The increasing climax usually occurred at 48 or 96 hours after the experiments were conducted. This indicates that the heat-resistance of both P. obconica and P. vulgaris are low in natural state.2. There were significant effects on both P. obconica and P. vulgaris with the treatments of SA and CaCl₂, which played a role in maintaining plant's normal physiological activities under the stress. And the content of the free proline, soluble protein, soluble carbohyarate, chlorophyll and the activity of SOD increased at the beginning and decreased later on but the relative electrical conductivity and MDA content increased continuously during the process, but the amplitudes were lower than the treatments without SA and CaCl₂. According to the analysis of the correlation of the indexes, the relative electrical conductivity had positive correlation with MAD (P＜0.01); free proline, soluble carbohyarate, soluble protein, SOD activity and chlorophyll had positive correlation with each other (P＜0.01); while the relative electrical conductivity and MAD had negative correlation with free proline, soluble carbohyarate, soluble protein, SOD activity and chlorophyll (P＜0.001).3. Under five levels of fixed temperature, the physiological and biochemical indexes showed that the heat-resistance of non-medicament treated P. obconica were always higher than that of P. vulgaris. In the experiments of medicament treatment Membership Function was introduced to have a comprehensive evaluation on heat-resistance of P. obconica and P. vulgaris under five levels of fixed temperature. The results were as follows: P. obconica 30℃: The compages of SA (150 mg·L^-1) and CaCl₂(1500 mg·L^-1) can increase plant's heat-resistance observably. 32℃: Using SA only (200 mg·L^-1) can increase plant's heat-resistance observably.34℃: The compages of SA (50mg·L^-1) and CaCl₂(1500 mg·L^-1) can increase plant's heat-resistance observably.36℃: The compages of SA (50 mg·L^-1) and CaCl₂(2000 mg·L^-1) can increase plant's heat-resistance observably.38℃: The compages of SA (150 mg·L^-1) and CaCl₂(1000 mg·L^-1) can increase plant's heat-resistance observably. P. vulgaris: 30℃: The compages of SA (150 mg·L^-1) and CaCl₂ (1500 mg·L^-1) can increase plant's heat-resistance observably.32℃: Using SA only (200 mg·L^-1) can increase plant's heat-resistance observably.34℃: Using SA only (150 mg·L^-1) can increase plant's heat-resistance observably. 36℃: The compages of SA (150 mg·L^-1) and CaCl₂ (500 mg·L^-1) can increase plant's heat-resistance observably. 38℃: The compages of SA (150 mg·L^-1) and CaCl (1000 mg·L^-1) can increase plant's heat-resistance observably.4. Using SA only (namely CaCl₂ was fixed to 0 mg·L^-1),200 mg·L^-1 and 150 mg·L^-1 can increase plant's heat-resistance and decrease free radical and cell membrane lipid peroxidation and protect biological macromolecule; but when the temperature was fixed to 36℃and 38℃, 100 mg·L^-1 and 50 mg·L^-1 of SA with certain consistency can not efficiently increase heat-resistance of P. obconica and P. vulgaris. Using CaCl₂ only (namely SA was fixed to 0 mg·L^-1),the consistency (500 mg·L^-1,1000 mg·L^-1,1500 mg·L^-1,2000 mg·L^-1) can not significantly increase plant's heat-resistance of P. obconica and P. vulgaris; When both SA and CaCl₂ were used, the fixed levels of CaCl₂ (≤1500 mg·L^-1) can increase heat-resistance of P. obconica and P. vulgaris at low level of SA(≤150 mg·L^-1); while at high level of SA(150～200 mg·L^-1), heat-resistance of P. obconica and P. vulgaris decreased along with the increment of CaCl₂ consistency past 1500 mg·L^-1.