3个木通品种光合特性的比较

摘要

In order to screen outAkebia cultivarwith high photosynthetic efifciencyand to provide theoretical basisfor introductionand cultivation ofAkebia, photosynthetic parametersand chlorophyll contentin threeAkebia cultivarswere determined by Li-6400xt portable photosynthesis system, photosynthetic-lightresponse curvesand photosynthetic-CO2 response curvesfor threeAkebiacultivars (A. quinata,A. trifoliata,A. trifoliatavar)wereanalyzed,and differences of photosynthetic characteristicsin three Akebia cultivarswere compared. Theresults showed that: (1)Most ofindexes ofA. quinatawere higher than those ofA. trifoliataandA. trifoliatavar,and the differences between themreached signiifcant level (P<0.5),including net photosyntheticrate (Pn), stomatal conductance (Gs), transpirationrate (Tr),intercellular CO2 concentration (Ci), chlorophyll content, themaximum net photosyntheticrate (Pmax),light saturation point (LSP),and carboxylation efifciency (CE); (2) Someindexes ofA. quinataarelower thanA. trifoliataandA. trifoliatavar.,and they werewater use efifciency (WUE),light compensation point (LCP),apparentquantum yield (AQY), darkrespirationrate (Rd), CO2 saturation pointand CO2 compensation point; (3) The order of three Akebia cultivars based on photosynthetic efifciencyfrom high tolowwasA. quinata,A. trifoliate,A. trifoliatavar.%为了筛选高光效的木通品种,为木通引种栽培提供理论依据,利用Li-6400xt便携式光合仪对3个木通品种(木通、三叶木通、白木通)的光合参数和叶绿素含量进行测定,分析了其光合-光响应曲线及CO2响应曲线,比较了3个品种之间光合特性的差异.结果表明,木通的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、胞间CO2浓度(Ci)、叶绿素含量、最大净光合速率(Pmax)、光饱和点(LSP)、羧化效率(CE)均高于三叶木通和白木通,且差异显著(P<0.05);木通的水分利用效率(WUE)、光补偿点(LCP)、表观量子效(AQY)、暗呼吸速率(Rd)、CO2饱和点和CO2补偿点均低于三叶木通和白木通;3个木通品种的光合效率由高到低的顺序为木通、三叶木通、白木通.