水氮运筹对伊犁河流域新垦土壤冬小麦旗叶SPAD值、净光合速率及产量的影响

【目的】针对新疆伊犁河流域新垦土壤土层薄、坡度大、保水保肥差等特性,开展研究获得新垦区最佳水肥调控措施。【方法】采用正交试验法研究了水、氮两因素对冬小麦旗叶SPAD值、净光合速率(Pn)及产量的影响。【结果】施纯氮量、灌溉总量是影响冬小麦生理性状和产量的主要因素,其次是施肥比例和灌溉频数;极差分析说明,施氮量和施肥比例对旗叶SPAD值的影响大于灌溉量和灌溉频数;而对净光合速率影响的主次排序是灌溉频数>施氮量>灌溉量和施肥比例。【结论】综合小麦叶片SPAD、净光合速率Pn以及产量方差分析的结果,推荐伊犁河流域新垦区冬小麦种植最佳施纯氮量为375 kg/hm2,灌溉量为4 500 m3/hm2,优化施肥制度为,全生育期追施两次氮肥,分别在返青期与拔节期,施肥量分配比例为6∶4,优化灌溉频数为6次。

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.