鱼藤(dErrIS TrIfOlIATA)是红树林常见伴生藤本植物。为了解其对潮间带高盐生境的响应和适应,研究了0~40的盐度对鱼藤幼苗生长、光合和叶绿素荧光的影响。结果表明:1)盐度低于20处理,幼苗生长相对较快;2)随盐度升高,根冠比下降、地下部分生物量受到影响大于地上;3)随盐度升高,净光合速率(Pn)、蒸腾速率(Tr)和气孔导度(gS)呈显著下降趋势;胞间CO_2浓度(CI)先降低后升高,盐度为20时达到最小值;Tr和气孔限制值(lS)与CI趋势相反;PSⅡ实际光化学量子产量显著下降,非光化学淬灭系数趋势与之相反。综上表明,盐胁迫对鱼藤幼苗生长、光合和叶绿素荧光均有影响,盐度越高,抑制越明显;低盐(盐度低于20)利于鱼藤幼苗生长。Derris trifoliata is a vine plant that commonly grows in the edges of mangroves in China.In order to understand its response and adaptability to salt stress in inter-tidal habitats, we manipulated 0～40‰salinities on the seedlings of D.trifoliata, and investigated the growth, photosynthesis and chlorophyll fluorescence of the seedlings.The results showed that D.trifoliata seedlings grew faster under 20‰salinity.The root-shoot ratio declined with the increase of salinity, indicating salt stress had a greater effect on underground biomass than aboveground biomass.Net photosynthetic rate (Pn), transpiration rate (Tr) and stomatal conductance (Gs) decreased significantly with the increase of salinity.Intercellular CO_2 concentration (Ci) decreased first and then increased, with the minimum value occurring under 20‰salinity; while transpiration rate (Tr) and stomatal limitation value (Ls) exhibited a reverse trend.PSⅡactual photochemical quantum yield decreased significantly, while non-photochemical quenching coefficient was opposite.The results suggested that higher salinity inhibited the growth, photosynthesis and chlorophyll fluorescence of D.trifoliata seedlings and that lower salinity (≤20‰) was propitious to the growth of D.trifoliata seedlings.国家自然科学基金项目(30600077);福建省自然科学基金(2006J0146
