Effects of Regulated Deficit Irrigation on the Photosynthetic Rate and Transpiration Rate of Greenhouse Grape under Delayed Cultivation

Effects of regulated deficit irrigation on the photosynthetic rate and transpiration rate of greenhouse grape were studied in Zhangye irrigation experiment station.The results showed that:the changes of net photosynthetic rate(Pn),transpiration rate(Tr)and stomatal conductance(Gs)were all double-peak curves.The moderate regulated deficit in the sprout stage had the highest WUE.Net photosynthetic rate, transpiration rate and stomatal conductance value had a significant positive correlation.Compared to contrast treatment,the correlation coefficient between the net photosynthetic rate and stomatal conductance under regulated deficit was higher than that in the contrast treatment,which showed that a certain water stress could improve the ability of plant regulating environment through the stomatal.