边坡先锋植物木豆的抗旱性

目的]探究干旱胁迫对木豆光合及生理生化指标的影响,为水电边坡生态修复中的物种筛选、植被群落的重建提供参考。方法]采用盆栽控水法进行干旱胁迫,测定木豆叶片净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、胞间CO2浓度(Ci)、水分利用效率(Pn/Tr)、丙二醛(MDA)含量、脯氨酸(Pro)含量和可溶性糖含量8个抗旱指标的变化。结果]木豆幼苗受水分变化的影响显著,在干旱胁迫下Pn、Gs、Tr、Ci、Pn/Tr等光合指标均显著下降,表现出不利的负向生理生态学响应;木豆叶片MDA、Pro和可溶性糖含量均显著增加以有效应对干旱胁迫。结论]木豆的抗旱能力较强,适应于干热地区的生态环境,是水电边坡治理与开发的优选灌木。

Drought Resistance Research for Slope Pioneer Plant Cajanus cajan

Objective] To explore the effects of drought stress on photosynthesis,physiological and biochemical indices of Cajanus cajan,and to provide scientific references for species screening and community reconstruction in ecological restoration of hydropower slope. Method] Pot wa-ter control method was used for drought stress of C.cajan.Changes of net photosynthetic rate (Pn),stomatal conductance (Gs),transpiration rate (Tr),intercellular CO2 concentration (Ci),water use efficiency (Pn/Tr),malondialdehyde (MDA),proline (Pro) and soluble glucose con-tent were detected in C.cajan.Result] C.cajan seedlings were greatly affected by the moisture change.Under drought stress,the Pn,Gs,Tr, Ci and Pn/Tr all significantly decreased,showing a negative photosynthetic response to the drought stress.MDA,Pro and soluble glucose content significantly increased,so as to effectively respond to drought stress. Conclusion] C.cajan has strong draught tolerance,can adapt to the ecolog-ical environment of dry-heat area.It is the optimal shrub to control degraded mountain land.