摘要
研究了南方杨树主栽品种‘中新4’(Populus deltoides CL.‘Zhongxin4’)幼株在6、7月两种不同生态条件下的光合生理特性。结果表明,高温(≥32℃)初期的净光合速率下降以气孔限制因素为主导;随高温时间延长和RH(相对湿度)降低,气孔及非气孔限制同时作用。‘中新4’对高温胁迫的耐受程度随RH的不同而变化,RH降低,温度胁迫程度加大,表观量子效率下降。在空气湿润条件下,Pn(净光合速率)与PAR(叶片光合有效辐射)呈正相关;而在空气干燥的条件下,Pn与RH呈正相关。
The photosynthetic physiology of poplar ‘Zhongxin 4＇ （Populus deltoides CL. ‘Zhongxin 4＇） was studied in this paper. The result showed that the net photosynthetic rate （Pn） decreased in high temperature stress （above 32℃）, and stomatal limitation was the most important factor at early stage. With the elongation of time in high temperature and reduction of relative humidity（RH）, stomatal and non-stomatal limitation acted simultaneously. The heat tolerance of poplar ‘Zhongxin 4＇ varied with RH. When RH decreased, the temperature stress increased, the solar energy utilization efficiency decreased. Under humid condition, Pn was positively correlated with photosynthetic active radiation （PAR）. Under add condition, Pn was positively correlated with RH.
出处
《亚热带植物科学》
2008年第3期26-30,共5页
Subtropical Plant Science
基金
广西自然科学基金(桂科自0542033)资助
