Effect of Irrigation Pattern on Photosynthetic Diurnal Changes of Intercropped Wheat in Irrigated Area in Oasis
In order to investigate the effects of alternative irrigation on photosynthetic characteristics of intercropped wheat,with conventional irrigation as the control,diurnal changes of photosynthetic rate (Pn) and its physio-ecological factors were measured.Direct effect and indirect effect of environmental factors on Pn were calculated with variance analysis,correlation analysis and path analysis,so as to provide scientific basis for implementation of alternative partial root-zone irrigation for wheat/maize intercropping.The results indicated that Pn under four treatments appeared as double peak curves,and the majority of peaks appeared at 12:00 and 16:00,and the former was higher than the latter.The photosynthesis showed "down ward" at midday.Diurnal changes of transpiration rate(Tr) in CW and AW3 treatment showed a similar trend to that of Pn.However,AW1 and AW2 were expressed as a single peak curve,and Tr of AW1 and AW2 treatment was relatively backward,as compared to Pn.Photosynthetic available radiation (PAR)was the major environmental factor that affected Pn of intercropped wheat under different treatments;meanwhile,it was subjected to stomatal conductance(Gs) and Tr.As for environmental factors,interaction between air temperature and air relative humidity has certain effect on Pn which was the main limiting factor.Therefore,intercropped wheat with alternative irrigation keep the similar Pn through adjusting leaf stomatal conductance and reducing luxury transpiration,thus improving leaf water use efficiency(WUE)compared to conventional irrigation.
Alternative irrigationIntercroppingWheatPhotosynthetic characteristicPath analysis
NETL
NSTL
万方数据
维普
