夏季高温环境下3个矾根品种的光合特性比较

在夏季高温环境中对3个矾根(Heuchera)品种进行光合特性研究。结果表明:3个矾根品种对强光利用能力较强，大小排序为:‘巴黎’（‘Paris’)＞‘好莱坞’（‘Hollywood’)＞‘草莓漩涡’（‘Strawberry+Swirls’)；在3个矾根品种中，具有明显的光合“午休”现象，’巴黎’具有最高的净光合速率（P_n）；3个品种的水分利用率(WUE)在上午较高，于11:00后WUE维持在较低水平，其大小排序为:‘巴黎’（1.13 mmol·mol^-1）＞‘草莓漩涡’（0.93 mmol·mol^-1）＞‘好莱坞’（0.62 mmol·mol^-1）；蒸腾速率（T_r）、气孔导度（G_s）与P_n呈现相似的双峰曲线变化，胞间二氧化碳浓度（C_i）则与P_n相反。相关性分析表明，植物光合作用与其生理环境因子存在着复杂的相互关系。

Photosynthetic Characteristics of Three Heuchera Varieties at High Temperature in Summer

The photosynthetic characteristics of three Heuchera cultivars, "Paris" (P), "Hollywood" (H), and "Strawberry swirls" (S), were investigated.Three cultivars all exhibited strong capabilities to use intensive light, and the order was P>H>S.All displayed a clear photosynthetic noon break.Cultivar P had highest net photosynthetic rate (P_n).Water use efficiency (E_WUE) of the three cultivars was the highest in the morning,became lower after 11 o’clock,and the order of E_WUE was P（1.13 mmol·mol^-1）＞S（0.93 mmol·mol^-1）＞H（0.62 mmol·mol^-1）.Transpiration rate (T_r) and stomatal conductance (G_s) showed similar changes compared with P_n.However,changes in intercellular carbon dioxide concentration (C_i) were opposite.Correlation analysis showed that there was complex relationship between plant photosynthesis and the physiological and environmental factors