土壤干旱胁迫对紫叶小檗和小叶黄杨光合生理特性的影响

Effects of Soil Drought Stress on Photosynthetic Physiological Characteristics of Berberis thunbergii cv. atropurpurea and Buxus sinica

[目的]研究紫叶小檗和小叶黄杨在不同土壤水分胁迫下的光合生理特性。[方法]在盆栽试验中,将土壤相对含水量设90%~95%、60%~65%、40%~45%和20%~25%4个梯度,分别为对照、轻度、中度和重度干旱胁迫处理,干旱胁迫后第10天测定2种植物的叶绿素荧光和光合作用参数。[结果]随着水分胁迫的加重,2种植物主要光合参数Pn、Tr、Gs逐渐降低;WUE先升后降,紫叶小檗在轻度水分胁迫时WUE最高,小叶黄杨在中度水分胁迫时WUE最高;两植物叶绿素荧光参数Fo升高,Fm、Fv、Fv/Fm、Fv/Fo降低,其中紫叶小檗的变幅均大于小叶黄杨。[结论]水分胁迫对紫叶小檗和小叶黄杨的光合生理特性产生较大影响,但二者变化幅度有差异,紫叶小檗对土壤水分胁迫更为敏感,小叶黄杨的抗干旱能力明显大于紫叶小檗。

[Objective] The propose was to study the photosynthetic physiological characteristics in Berberis thunbergii cv.atropurpurea and Buxus sinica under different soil water stress.[Method] In the pot test,the relative water contents in the soil were set up as 4 grades of 90%-95%,60%-65%,40%-45% and 20%-25%,which were the CK and light,middle and heavy drought stress treatment.The chlorophyll fluorescence and photosynthetic parameter of 2 plants were determined on 10th after drought stress treatment.[Result] With the increase of water stress degree,the main photosynthetic parameter such as Pn,Tr and Gs of the 2 plants were gradually decreased;WUE of the 2 plants were increased first and then reduced,in which,WUE of B.thunbergii cv.atropurpurea was the highest in light water stress,but that of B.sinica was the highest in middle water stress;as for the chlorophyll fluorescence parameter of the 2 plants,Fo was increased,while Fm,Fv,Fv/Fm and Fv/Fo were decreased,in which,B.thunbergii cv.atropurpurea had higher change than B.sinica.[Conclusion] The water stress had greater effects on the photosynthetic physiological characteristics of B.thunbergii cv.atropurpurea and B.sinica,but their change extent differed.B.thunbergii cv.atropurpurea was more sensitive to soil water stress and B.sinica had greater drought resistance than B.thunbergii cv.atropurpurea.