3种紫金牛属植物光合光响应特性的研究

Photosynthesis Light Response Characteristics of Three Ardisia Species

利用LI-6400便携式光合测定系统对人工遮阳栽培的东南紫金牛、朱砂根、红凉伞3种紫金牛属植物叶片进行光模拟试验，结果表明：在低光照下，随着光合有效辐射强度（PARi）的增强，3种植物的净光合速率（Pn）增大，蒸腾速率（Tr）加大，叶温（Tf）均升高，气孔导度（Gs）迅速增大，胞间CO2浓度（Ci）值下降，水分利用效率（WUE）增加。当PARi达到400 μmol·m^-2·S^-1时，出现了明显的光抑制现象；当PARi达到800 μmol·m^-2·S^-1时，Gs下降，气孔运动受到影响。3种植物的光合饱和点（LSP）在199．2518—281．5106μmol·m^-2·S^-1，光补偿点（LCP）在11．9340-51．6789μmol．m^-2.S^-1，最大WUE为2．27-7．56μmolCO2·mmol^-1 H2O，说明3种植物耐阴喜湿的特性，可以适应室内的生态环境。对3种植物进行对比分析表明，东南紫金牛的LSP及LCP相对较高，Tr比较大，Tf变幅小，Gs大，说明东南紫金牛与朱砂根及其变种红凉伞相比，有较好的适应强光的能力，生长势强。

Light simulation experiment on Ardisia sieboldii, A. crenata and A. crenata vat. bicolor cultivated under shade and determination by portable photosynthesis system （LI-6400） demonstrated that net photosynthetic rate （Pn）, transpiration rate （Tr）, leaf temperature （Tf）, stomatal conductance （Gs） and water use efficiency （WUE） of three plants increased, while intercellular CO2 concentration （C/） decreased with low light and enhancement of photosynthetic active radiation （PARi） treatment. When PARi reached 400μmol . m^-2 . s^-1, there had an obvious inhibition of photosynthesis, while PARi topped 800μmol. m^-2 . s^-1, stomatal conductance reduced and stomatal movement were affected. Light saturation point（LSP）, light compensation point（LCP） and maximum water use efficiency of three plants were 199.251 8 - 281.510 61μmol. m^-2 . s^-1, 11.934 0 - 51.678 9 μmol . m^-2 . s^-1and 2.27 - 7.56 μmolCO2 . mmol^-1H2O respectively. The experiment resulted that three Ardiasia species had property of shade tolerance and hygrophilous, could adapted indoor environment. Contrastive analysis indicated that A. sieboldii had higher light saturation point and compensation point, greater transpiration rate and stomatal conductance and less variation range of leaf temperature than the other two species. It had better ability to adapt intense light and hail stronger growth vigor.