| 'Climbing plant' is the general name for plant group which possesses special life type. It cannot stand independently but depends on other objects to assist it in its upward ascent.This is done by winding the objects with caulis or climbing using a 'climbing organ'. This group of plants is widely distributed all over the world in a wide variety of species, and they therefore, have a significant effect on the appearance and structure of community, particularly on those of tropical and subtropical regions. Many species possess significant economic value, however, some of them can also severely endanger the forest community, agricultural crops and other plant life. The current knowledge on climbing plants comes mainly from observations of tropical climbing plants. Despite the high level of ecological research achieved so far, research in specific area is still far from adequate, lacking not only depth and extent, but also with regards to other areas such as, the mechanism of ecological adaptation for liana.Climbing plants are perfect for studying plant behavior ecology. This is so because climbing plants are likely to encounter intensive-changing environmental condition during their growth (especially change of illumination). Secondly, there is a large proportion (30-40%) of climbing plants which belong to dioecism, and hence a gap between male and female plants on morphology, biological characteristic, economic value and so on. This dissertation focuses on herbaceous climbing plants, perennial or annual species such as dioecious Trchosahthes kirilowii Maxin and Dioscorea opposita thumb, and monoecious Luffa cylindrical(L)Roem, It attempts to discover how climbing plants adapted to various environments and the mechanism of adaptation from aspects ofphysiological and reproductive ecologiesAt present, due to overuse of Chlorofluorocarbons(CFCs), the ozonosphere has become thinner and thinner, and the Ultraviolet-B( UV-B)radiation has increased considerably. Human beings now realize the damaging effects of enhanced UV-B radiation. Research has shown that, even if destruction of the ozonosphere is stopped, it will still need about 100 years to renew it to a normal state. As a result, studies on the effects of ozonosphere thinning and the consequences of UV-B radiation on plant and ecosystem will not decline but on the contrary, is likely to increase in popularity. In order to provide scientific evidence on the ecological aftereffect of UV-B radiation, this dissertation uses climbing plants to investigate the effect of UV-B radiation on them under greenhouse and field conditions.Effects of UV-B radiation on Trchosahthes kirilowii Maxin seedlings in greenhouse-grown were first investigated. The results indicated that: (1) In comparison to the controls, exposure to 2.9iw/cm2 UV-B radiation significantly decreased chlorophyll a and chlorophyll b content and the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase(ASP) in leaves, but, however, significantly increased the membrane permeability and lipid peroxidation(MDA) content, led to accumulation of plant contents of endogenous abscicic acid(ABA), decreased contents of endogenous indole-3-acetic acid(IAA) and gibberellic acid(GA1/3) while it increased content of endogenous zeatinriboside(ZR). Exposure to UV-B radiation reduced the height, leaf area of plants, and the weight of roots, stems and leaves. As a result, total biomass and accumulation of dry matter were decreased. Exposure to UV-B radiation significantly increased the stomatal diffuse resistance and decreased the transpiration rate; however it hardly affected the water content of seedlings. (2) In comparison to the controls, additions of 2mg/L a-naphthalene acetic acid(ct-NAA) increased the content of chlorophyll(Chl) and carotenoids(Car) and the activities of SOD, CAT, POD, and ASP, but did not significantly affect membrane permeability and MDA content hi leaves. The addition of a-NAA could significantly increase the contents of IAA and GA1/3, just s...
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