4种苦苣苔科植物光合特性的比较

以苦苣苔科植物半蒴苣苔（Hemiboea henryi Clarke）、温州长蒴苣苔（Didymocarpus cortusifolius（Hance）W．T．Wang）、牛耳朵（Chirita eburnea Hance）和大花旋蒴苣苔（Boea clarkeana Hemsl．）为材料，测定并比较了它们的生理生态因子、光合作用和叶绿素荧光参数．结果表明：4种苦苣苔科植物的净光合速率日变化曲线均为双峰曲线，峰形也相似；4种苦苣苔科植物均有较低的光补偿点和光饱和点，以及较高的CO2补偿点和CO2饱和点，说明低光照（600～750μmol·m-2·s-1）和高CO2浓度（1277—1965mg／m3）可以有效促进植物的生长和发育．叶绿素荧光参数的测定结果显示：随着光合有效辐射从0μmol·m-2·s-1增加到1400μmol·m-2·s-1，4种苦苣苔科植物的光系统Ⅱ实际光化学量子产量和光化学猝灭值逐渐下降，表观电子传递速率和非光化学猝灭值则增加；光化学量子产量、表观电子传递速率和光化学猝灭的大小顺序为温州长蒴苣苔〉牛耳朵〉半蒴苣苔〉大花旋蒴苣苔，非光化学猝灭均值的大小顺序为牛耳朵〉半蒴苣苔〉温州长蒴苣苔〉大花旋蒴苣苔．表明4种苦苣苔科植物中，牛耳朵同时具有较高的光利用能力和光适应能力，是引种开发的优选品种．

Comparative study on the photosynthesis and chlorophyll fluorescence of four Gesneriaceae species

Eco-physiology parameters, photosynthesis and chlorophyll fluorescence of four endangered Gesne- riaeeae species, Herniboea henryi Clarke, Boea clarkeana Hemsl. , Chirita eburnea Hance, and Didymocarpus cortusifolius （ Hance） W. T. Wang, were determined. The curve of diurnal variation of leaf photosyntbeses of these Gesneriaceae species were similar and showed two peaks in a day with ＂Wuxiu＂ phenomenon. The low light compensation points and light saturation points and the high CO2 compensation points and CO2 saturation points suggested that low irradiation （600-750 μmol·m-2·s-1） and high CO2 concentration （1 277 - 1 965 mg/m3 ） would enhance plant growth and development. The study on chlorophyll fluorescence parame-ters of four Gesneriaceae species showed that the quantum yield of PS Ⅱ linear electron （ Yield） and photo- chemical quenching coefficient （qP ） decreased as photosynthetic active radiation （PAR ） increased from 0 to 1 400 μmol·m-2 ·s-1, while the apparent photosynthetic electron transport rate （ ETR） and coefficients of non-photochemical fluorescence quenching （ qN） had reverse trends. The values of Yield, ETR, qP and qN obtained from the four Gesneriaceae species had the different sequences, i e, D. cortusifolius 〉 C. eburnea 〉 H. henry 〉 B. clarkeana for Yield, ETR and qP, and C. eburnea 〉 H. henryi 〉 D. cortusifolius 〉 B. clarkeana for qN. The chlorophyll fluorescence parameters of four Gesneriaceae species showed that the photosynthetic physiological functions of C. eburnea were better than those of the others, and it would be a suitable candidate used as preference species.