摘要
以卷柏为试材,从卷柏的净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度与大气CO2浓度比值(Ci/Ca)、蒸腾速率(Tr)和水分利用效率(WUE)5个生理指标入手,研究了不同程度的干旱胁迫对卷柏光合日变化的影响。结果表明:正常浇水的卷柏光合速率日变化曲线为双峰,具有明显午休现象;干旱胁迫使得卷柏的光合速率、气孔导度、蒸腾速率降低,对植株的光合日变化影响明显;轻度干旱胁迫条件下,卷柏的光合作用日变化与CK基本一致;中度干旱胁迫条件下,卷柏光合速率日变化曲线仍表现出双峰现象,但全天净光合速率值明显下降;重度干旱胁迫条件下,卷柏光合速率日变化曲线的"双峰"和"午休"现象消失,气孔导度、蒸腾速率的数值变化范围较小,且接近于零。
Taking Selaginella tamaariscina as experimental materials, from five physiological indexes of Selaginella tamariscina starting, the net photosynthetic rate （Pn）, stomatal conductance （Gs）, the ratio of intercellular CO2 concentration and atmospheric CO2 concentration （Ci/Ca）, transpiration rate （Tr） and water use efficiency （WUE）, diurnal photosynthetic changes of Selaginella tarnariscina under different drought stress conditions were studied. The results showed that the net photosynthetic rate of the normal watering plants （CK） showed a bimodal curve of diurnal variation and had a character of photosynthetic depression at midday;The net photosynthetic rate, stomatal conductance and transpiration rate of Selaginella tamariscina decreased under drought stress; Diurnal photosynthetic changes of Selaginella tarnariscina under mild drought stress condition were the same as CK; Diurnal photosynthetic changes of Selaginella tamariscina under moderate drought stress condition also showed a bimodal curve, but the net photosynthetic rate all day significantly decreased; The midday depression phenomenon and bimodal curve of SelagineUa tamariscina under severe drought stress condition disappear, the change of stomatal conductance and transpiration rate was close to zero range all day.
出处
《北方园艺》
CAS
北大核心
2012年第6期61-63,共3页
Northern Horticulture
基金
辽宁省交通厅资助项目(200612)
关键词
卷柏
干旱胁迫
净光合速率
光合日变化
Selaginelta tamariscind
drought stress
net photosynthetic rate
photosynthetic change
