Effects of Irrigation and Nitrogen on Flag Leaf SPAD,Net Photosynthetic Rate and the Yield of Winter Wheat in the Freshly Plowed Soil of Ili River Basin,Xinjiang

【Objective】Xinjiang Ili River Basin is very important reserve agricultural exploit area in China.The soil type is freshly plowed soil,and its characteristics,thin soil layer,steep slope,lower nutrient and low water preserving capability.Higher water-nitrogen management is demanded to overcome this disadvantage.Therefore,it is significant to discuss the effect of irrigation and nitrogen on flag leaf SPAD,net photosynthetic rate and the yield of winter wheat.【Method and Result】Orthogonal experiment was used and the results showed that total amount of irrigation and nitrogen used in the soil were major factors,followed by fertilizer assignment,irrigation frequency.Range analysis results showed that the influence of amount of nitrogen and irrigation on flag leaf SPAD was greater than that of fertilizer assignment and irrigation frequency.However,the primary and secondary order that influence Pn is irrigation frequency nitrogen amount irrigation amount and fertilizer assignment.【Conclusion】A combination of range analysis results told us that the optimal amount of nitrogen and irrigation is 375 kg/hm2 and 4 500 m3/hm2.The optimal fertilizer regime is top-dressing at the growing period,that is at the green and jointing stage,respectively.Fertilizer application proportion is 6∶ 4.In all growing period,optimum irrigation frequency is six times.