摘要
使用LI-6400便携式光合测定系统对濒危植物广西火桐幼树叶片净光合速率(Pn)及其影响因子日变化速率进行测定,并进行相关分析、逐步回归分析和通径分析。结果表明:广西火桐净光合速率(Pn)日变化曲线为"双峰"型,变化趋势与蒸腾速率(Tr)相同;具有明显的"光合午休"现象,午间净光合速率(Pn)降低主要由气孔导度(Gs)降低引起;影响广西火桐叶片净光合速率(Pn)的主要生理因子是蒸腾速率(Tr),主要生态因子是光照强度(PAR)和空气相对湿度(RH)。栽培管理中可通过增加透光度、适当浇水等措施来调节蒸腾速率,提高净光合速率,促进苗木快速生长。
The diurnal variation and the factors affecting net photosynthetic rate（Pn） in Erythropsis Kwangsiensis were measured using LI-6400 portable photosynthetic analyzer in sunny days during October 2009,and the data were analyzed statistically for correlation,stepwise regression and path analysis.The results showed two different peaks in the curve of diurnal variations in Pn,and a similar trend was observed with transpiration rate（Tr）.The midday depression in photosynthesis was significant,and it was principally caused by decrease in stomatal conductance（Gs）.The main physiological factor which affected diurnal variation in Pn was found to be Tr,and the main ecological factors were the light intensity（PAR） and relative humidity（RH）.The light transmittance increase,proper management of irrigation during the cultivation may help in adjusting Tr,increasing Pn,and promoting the growth of seedlings.
出处
《广西农业科学》
CSCD
2010年第11期1165-1169,共5页
Guangxi Agricultural Sciences
基金
广西自然科学基金项目(桂科自0832222)
中国科学院知识创新工程项目
关键词
濒危植物
广西火桐
净光合速率
生理生态因子
通径分析
endangered plant
Erythropsis kwangsiensis
net photosynthetic rate
physio-ecological factors
path analysis
