高温胁迫对希蒙得木幼苗叶片光合生理特性的影响

在人工气候室内采用盆栽土培的方法,研究了不同程度高温胁迫对希蒙得木幼苗叶片光合作用和相关生理指标的影响.结果表明,对照(CK)叶片净光合速率(Pn)日变化呈“双峰”型,高温处理后叶片净光合速率日变化呈“单峰”型,T1和T2处理比CK同一时间峰值分别下降了17.4％和35.5％.T1和T2处理叶片的蒸腾速率(Tr)显著降...

Effects of High-temperature Stress on Physiological Characteristics of Seedling Leaf in Simmondsia chinensis

Using phytotron to simulate high temperature environment,the study was made on the physiological characteristics of leaves of S.chinensis under different degree of high-temperature stress(CK,T1,T2) were studied.The results showed that diurnal change of net photosynthetic rate(Pn) of CK was double peak type,but those under T1 and T2 were single-peak type and they decreased by 17.4% and 35.5% respectively than CK.With the intensification of the stress temperature,transpiration rate(Tr) and stomata conductance(Gs) decreased significantly,while the intercellular CO2 concentration(Ci) increased.It showed that the decrease of Pn wasn't mainly stomata factor.Moreover,the leaf relative water content(LRWC) decreased significantly.The content of chlorophyll(Chl),relative conductivity,the content of malondialdehyde(MDA),the activity of peroxidase(POD) and superoxide dismutase(SOD),Proline(Pro) and soluble sugar increased significantly with the intensification of the stress temperature.The research indicated that S.chinensis had a good high-temperature resistance capability.