| Sunfan originated from Australia, is excellent perennial ornamental flower. With the characteristic of fast growth, good adaptability, easy maintenance, blossom in every year, much flowers, long flowering period, floriated beautiful, bright red and rich color and so on. It was introduced and planted in Chongqing and hubei province by 948 project of State Bureau of Forestry. Because of big variance between the origin and our country in climate, soil, environment and so on, it is great important for introduction to have research on physiological adaptation of sunfan in our country. The experiments of light, high temperature, water stress on cutting seedlings of sunfan were conducted to study the effect of morphological characteristics and physiological response of Scaevola aemula under light stress, high temperature stress, water stress. And physiological adaptive capacity under different environment condition was confirmed and mechanism of response of cutting seedling of sunfan to light, high temperature and water stress was explored. It provided theory reference for introduction and resource assessment of Sceavola aemula. And it also was reference for the choice of environment condition for introduction place of sunfan.The experiment of high temperature stress was used to study the variance of physiological index, such as growth characteristic, chlorophyll, soluble protein, soluble sugar, proline, MDA, antioxidant enzymes system, and so on. And the experiment was also used to explore adaptation and physiological response mechanism of sun fan to the high temperature. The results indicated that high temperature stress has large impact on morphology and physiological character of sunfan. As temperature arise. injury index showed a rising trend; Pigment like Chla, Chlb, Ca, Chla/Chlb, Chl(total) and osmoregulation substance like soluble protein, soluble sugar were rising first and then descended. While MDA, Pro, and POD activity descending first and the rising. And SOD, CAT activity,Car/Chl(total) were rising. With the elongation of treatment time, Most of physiological index of cutting seedlings showed regular variation. The content of Pro descended gradually when was treated at 35℃, while content of soluble protein and SOD activity first descended and then went arise. When was treated at 40℃,the content of pigment and chlorophyll gradually elevates With the elongation of treatment time. The content of soluble protein, SOD, and POD decline gradually. The content of pro declined first and then went arise. However, the content of MDA showed the opposite variation trend. When was treated at 46℃, cutting seedling showed obvious damage status with the elongation of treatment time. small leaves, wilt and tend to death. And it was very significant difference in injury index compared to control; The content of Chla, Chlb, Car, Chl(total) and soluble protein declined gradually with the time prolonged. But content of MDA, Pro and CAT,POD,SOD activity showed rising trend; the content of soluble sugar descend first and then increased with 1.5 higher than control after 3 days treatment. Correlation analysis indicated that it has significantly correlation between physiological index, which indicated that it has cooperative response capacity to high temperature stress. The production of chlorophyll and carotenoid was inhibited. osmoregulation substance such as soluble sugar, soluble protein and CAT,POD,SOD activity was induced by high temperature stress. And the response system of cooperative physiology to the high temperature stress of sunfan was formed.Through water stress experiments, the changes of some physiological indices including Chlorophyll, soluble protein, soluble sugar, proline, MDA, and antioxidant enzymes system of Sunfan under different water condition were studied, as well as changes of growth properties of Sunfan, to discuss Sunfan'adaptability and physiological response mechanism under different water condition. The results showed that water stress have greater effect on Sunfan' morphological and physiological characteristics. The Sunfan showed strong injury symptom as water stress intensified; with the extension of time, injury indices increased, leaves become smaller and their color became shallow. Under continuous drought conditions, leaves withered gradually and finally died with rapid decrease of soil water; with the flooded treatment, the edges of leaves had necrosis symptoms. With the natural drought treatment, Chla, Chlb and Chl(Total) all decreased rapidly to 81.6%,94.4%, 84.5% of the control; the content of carotenoids decreased; Chla/Chlb,Car/Chl(Total),POD all first increased then declined; The content of MDA presented down-up-down trend; The content of soluble sugar, soluble protein all first declined and then increased; The content of proline, CAT,SOD all presented a rising trend with the increase of time, and CAT was higher than control in each time and SOD was 1.3 times as many as the control. With the flooded treatment, as process time increased. Chla, Chlb and Chl(Total) all decreased to 83.8%,99.7%,87.4% of control:the content of carotenoid, POD all presented decreased-increased-decreased trend; Chla/chlb,Car/chI(Total),SOD all showed trend of that first increased then declined; MDA and soluble protein all presented down-up-down trend; Soluble sugar first decreased then increased; The activity of CAT and proline all presented a rising trend with the increasing of time, and CAT was higher than the control in each time and the content of proline was 1.7 time as many as the control. Correlation analysis indicated that it has significantly correlation between physiological index, which indicated that it has cooperative response capacity to water stress. The production of chlorophyll and carotenoid was inhibited. osmoregulation substance such as soluble sugar, soluble protein and CAT,POD,SOD activity was induced by water stress. And the response system of cooperative physiology to water stress of sunfan was formed.The experiment of different light intensity on sunfan was used to study the variance of physiological index, such as growth characteristic, chlorophyll, soluble Protein, soluble sugar proline, MDA, antioxidant enzymes system, and so on. And the experiment was also used to explorer adaptation and physiological response mechanism of sunfan under different light intensity. The results indicated that different light intensity has big impact on morphology and physiological characteristic of sunfan. As light transmittance declined, and the time prolonged. More leaves, small leaf area, fine plant and the injury index became higher. It has significant difference compare to control, and the plant was nearly to death under serious stress when was treated at light transmittance of 18.5%; As transmittance declined, Chla, Chlb, Car, Chl(Total) increased significantly, Chla/chlb reduced evidently, and Car/(Total) decreased firstly, then went arise and decreased again:The content of MDA went increased. first and then decreased When was treated at serious stress (18.5%), the peak was 1.3 higher than the control; Soluble protein increased with 1.5 higher than control; Soluble sugar decreased gradually and was lower than the control; Content of Proline increased with the time prolonged; SOD activity increased first and then decreased, and the peak was about 5.3 higher than control. POD activity showed rising trend. Correlation analysis indicated that it has significantly correlation between physiological index, which indicated that it has cooperative response capacity to different light intensity. The production of chlorophyll and carotenoid was inhibited. osmoregulation substance such as soluble sugar, soluble protein and CAT,POD,SOD activity was induced by weak light. And the response system of cooperative physiology to different light intensity of sunfan was formed. |
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