不同栽培密度对猫爪草果期光合蒸腾特性的影响

在不同栽培密度条件下,利用CI-340便携式光合系统,对猫爪草果期的净光合速率、蒸腾速率及相关的生理因子(叶温、气孔导度、胞间CO2浓度)和生态因子(光合有效辐射、大气CO2浓度、气温、大气相对湿度)进行了测定分析,结果表明,随着密度的增加,净光合速率和气孔导度先缓慢增加后显著降低,蒸腾速率呈现高-低-高趋势,胞间CO2浓度随密度增加显著升高。经过相关性分析,影响猫爪草光合蒸腾特性的主要因子为大气相对湿度(RH)、大气CO2浓度(Ca)、气孔导度(Gs)和叶温(Tl)。在高密度条件下非气孔因素影响净光合速率(Pn)的变化,在中低栽培密度条件下,气孔因素影响净光合速率(Pn)的变化。

Effects of Different Cultivation Density on Photosynthesis and Transpiration of Ranunculus ternatus Thunb.during the Fruiting Stage

Under different cultivation density,net photosynthetic rate,transpiration rate and related physiological factors(leaf temperature,stomatec conductance,intercellular CO2 concentration) and ecological factors(PAR radiation,atmospheric CO2 concentrations,temperature and relative humidity of the atmosphere) of Ranunculus ternatus Thunb.during the fruiting stage were mea-sured and analyzed by using CI-340 portale photosynthesis system.The results showed that with the increase of the cultivation density,the net photosynthesis and stomatic conductance were increased slowly firstly,and then decreased significantly.While the transpiration rate showed a trend of high-low-high,internal CO2 concentration significantly increased with the increase of density.Coefficient analysis showed that the atmosphere relative humidity(RH),CO2 concentration in the field,stomatic conductance(Gs) and leaf temperature(Tl)were the main factors influencing the characteristics of photosynthesis and transpiration.Non-stoma-related factors affected net photosynthetic rate(Pn) changes under high-density conditions,while under low-density conditions stomatic factors affected net photosynthetic rate(Pn) changes.