边坡先锋植物木豆的抗旱性

Drought Resistance Research for Slope Pioneer Plant Cajanus cajan

[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。

[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 water control method was used for drought stress of C. cajan. Changes of net photosynthetic rate（ Pn）,stomatal conductance（ Gs）,transpiration rate（ Tr）,intercellular CO2concentration（ Ci）,water use efficiency（ Pn / Tr）,malondialdehyde（ MDA）,proline（ Pro） and soluble glucose content 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 ecological environment of dry-heat area. It is the optimal shrub to control degraded mountain land.