Photosynthetic Indexes Variation of Xanthoceras sorbifolia under Drought Stress
The aim of this research is to determine the threshold of irrigation so that it can make sure of the normal growth of Xanthoceras sorbifolia at the same time of saving water by exploring photosynthetic physiology changes of X.sorbifolia under drought stress.In this study,through pot experiment,the photosynthetic indexes and fluorescence parameters of X.sorbifolia were determined by using Li-6400 under 5 water densities.The soil water content was controlled respectively at 80％ (T1),60％ (T2),40％ (T3),20％(T4) of the maximum water holding capacity,with normal irrigation as CK.The result showed that the parameters(Pn,Tr,Gs,qP) decreased with the increase of drought stress time and drought gradient,which caused the photosynthesis restrained.The fluorescence parameters (Fv/Fo,Fv/Fm and WUE) decreased with the aggravation of water stress and they showed T2 ＞ T3 ＞ T4.However,the photosynthetic parameters (Pn,Gs,Ci) of T1 decreased because of adequate irrigation.The seedling photosynthetic indexes of X.sorbifolia showed CK ＞ T2 ＞ T1 ＞ T3 ＞ T4 by PCA (principle component analysis) under different water condition.Results indicate that WUE is the highest and all the photosynthetic indexes perform better when field water content is 60％.
国家科技期刊平台
NSTL
万方数据
维普
