摘要
宁夏红枣开花期,用CIRAS-1便携式光合仪测定田间活体红枣的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、细胞间隙CO2浓度(Ci)等光合生理生态因子,以及光合有效辐射(PAR)、大气CO2浓度(Ca)、相对湿度(RH)、大气温度(Ta)、叶温(Tl)等环境因子的日变化。结果表明:红枣Pn日变化曲线为"双峰"型,午间有明显的"午休"现象,气孔因素是导致其"午休"的主要原因。Tr、Gs和Ci的日变化曲线均为"双峰"型,红枣叶片Pn随环境因子日变化的最优逐步多元回归方程为YPn=-49.168-0.002 21 xPAR+1.776 xTa-0.445 xTl+0.003 736 xCi+0.67 xRH(R2=0.994,P<0.05),Ta和RH是对Pn直接影响最大的生态因子,而其他因子间接影响Pn的变化。
During the full-bloom stage of Ningxia ZiZyphus jujube,the diurnal dynamics of photosynthetic rate（Pn）,transpiration rate（Tr）,stomatal conductance（Gs）and internal CO2（Ci）,as well as the ecological factors photosynthetically active radiation（PAR）,CO2 concentration in field（Ca）,relative humidity（RH）,air temperature（Ta）and lear temperature（Tl）were measured.The results showed that the diurnal net photosynthetic rate of ZiZyphus jujube in sunny day exhibited double-peak pattern.There was a significant midday depression with ZiZyphus jujube,which was caused principally by stomatal factors such as stomatal conductance.The curves of diurnal variation in Tr,Gs and Ci of ZiZyphus jujube leaves also had two peaks.The most optimal equation describing diurnal variation of Pn was attained by the method of stepwise multiple—regression as follows：YPn=-49.168-0.002 21 xPAR＋1.776 xTa-0.445 xTl＋0.003 736 xCi＋0.67 xRH（R2=0.994,P0.05）.With the analysis of partial correlation and path on Pn and environmental factors,it was concluded that Ta and RH had the greatest effect on the diurnal dynamics of Pn,while other factors indirectly affected Pn.
出处
《现代农业科技》
2012年第4期278-280,282,共4页
Modern Agricultural Science and Technology
基金
宁夏回族自治区科技厅科技攻关项目"枣树病虫害演变规律及预测预报和综合防控技术研究"
关键词
红枣
光合速率
环境因子
日变化
逐步多元回归
通径分析
ZiZyphus jujube
photosynthetic rate
environmental factors
diurnal variation
stepwise multipie-regression
path analysis
