Effects of Choline Chloride on Antioxidative Metabolism and Catalpol Content of Rehmannia glutinosa under Drought Stress

Effects of choline chloride(CC) on antioxidative metabolism,permeability of cell membrane,chlorophyll fluorescence parameters and catalpol content of Rehmannia glutinosa were studied by spraying CC solutions in diffreent concentrations(0,100,300,500 mg/L) on the leaves of Rehmannia glutinosa subjected to drought stress.The results showed that higher activities of superoxide dismutase(SOD),ascorbate peroxidase(APX) and catalase(CAT) were maintained in leaves pretreated with CC under drought stress.Therefore,content of malondialdehyde(MDA) and relative electrical conductivity were reduced.Simultaneously,degradation of chlorophyll was slowed down and higher Fv/Fo,Fv/Fm,ФPSⅡ and qP in leaves pretreated with CC were maintained.Consequently,yield and catalpol centent of Rehmannia glutinosa rhizome were obviously increased under drought stress.Comparatively,the concentration of 300 mg/L had the best effect.