通过盆栽实验,研究了干旱胁迫对南方常用绿化与护坡豆科灌木山毛豆Tephrosia candida、望江南Cassia occidentalis和猪屎豆Crotalaria pallida生物量分配、水分利用效率和生理特性的影响。结果表明:随着干旱胁迫程度的加剧,3种灌木的生物量下降,根冠比增加;干旱胁迫可提高3种灌木的水分利用效率,其中山毛豆和望江南在中度干旱下效率最高,猪屎豆在轻度干旱下最高;随着干旱胁迫程度的增加,3种灌木的脯氨酸(Pro)含量持续上升,望江南和猪屎豆的超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量也逐渐增加,但山毛豆的SOD活性和MDA含量则呈现出先增加后降低的趋势;干旱胁迫降低了3种灌木的叶绿素含量,并影响其叶绿素荧光动力学参数,其中变化幅度最大的是猪屎豆;3种灌木的抗旱性从强到弱依次为望江南〉山毛豆〉猪屎豆。
The potted experiments were conducted to investigate the biomass allocation, water-use efficiency and physiological responses of Tephrosia candida, Cassia occidentalis and Crotalaria pallida. The results show that the biomass of three kinds of shrubs decreased and root-shoot ratio increased with the drought degree aggravating; Drought stress could improve the water-use efficiency of three kinds of shrubs, and the highest water use efficiency in T. candida and C. ccidentalis appeared when they were subjected to moderate drought stress, but in C pallida was at low drought stress; When the drought stress increased, the proline contents of the three shrub species increased gradually, the superoxide dismutase (SOD) activity and malondialdehyde (MDA) content of C. ccidentalis and C. pallida increased, but the SOD activity and MDA content of T. Candida increased first and then reduced; Drought stress decreased chlorophyll contents of three kinds of shrubs, and their chlorophyll fluorescence kinetics parameters were affected, of them C. pallida had the maximum changing range. The order of three species in drought resistance was: C. ccidentalis 〉 T. candida 〉 C. pallida.