水氮配施对轮作冬小麦-夏玉米灌浆期光合特性的影响

研究不同水氮配施对轮作冬小麦-夏玉米灌浆期叶面积指数、光合速率、蒸腾速率及叶片水分利用效率的影响。结果表明,冬小麦旗叶光合速率和蒸腾速率均以处理W1500N210最高,叶面积指数和叶片水分利用率均以处理W1500N210最高,夏玉米叶片光合速率在处理W1500N210达到最高,蒸腾速率则以处理W1500N210最高;灌水和施氮及其交互效应对冬小麦、夏玉米叶面积指数、叶片光合速率、蒸腾速率和叶片水分利用率均有显著影响;冬小麦、夏玉米灌浆期叶面积指数、叶片光合速率、蒸腾速率和叶片水分利用率均随施氮量和灌水量的增加而增加;但施氮量超过210kg／hm^2时不再显著增加。

Effects of Nitrogen and Irrigation on the Photosynthetic Characteristics at Filling Stage in Rotation of Winter Wheat and Summer Maize

The field experiments were performed using split-plot design to investigate the effects of different nitrogen and irrigation levels on the leaf area index and photosynthetic characteristics at filling stage in rotation of winter wheat and summer maize.The results showed that: the highest values of net photosynthetic rate(Pn) and transpiration rate(Tr) were observed in treatment W1500N210 and the highest leaf area index(LAI) and leaf water use efficiency(LWUE) were obtained in treatment W1500N270 at the filling stage of winter wheat;the maximal Tr and Pn were got in treatment W1500N270 and W1500N210 at the filling stage of summer maize,respectively.The significant effects of irrigation,nitrogen and their interaction were found in LAI,Tr,Pn and LWUE of winter wheat and summer maize.LAI,Tr,Pn and LWUE of winter wheat and summer maize increased with the increase of irrigation and nitrogen,which did not significantly increase when the nitrogen contents exceeded 210 kg/hm2.