中文摘要：

为明确新疆干旱区滴灌春小麦水氮耦合对小麦根系的时空分布、水氮利用率及产量的影响,以新春19号为试验材料,利用田间定位试验研究了4个灌水量处理（W0：0 m^3/hm^2、W1：1 500 m^3/hm^2、W2：4 500 m^3/hm^2、Wck：3 750m^3/hm^2）、4个施氮量处理（N0：0kg/hm^2、N1：150kg/hm^2、N2：450kg/hm^2、Nck：300kg/hm^2）对拔节期、抽穗期、开花期及成熟期小麦根系根长密度、根体积、根质量等在0-100cm土层的垂直分布、动态变化和产量及其构成因素的影响。结果表明,0-20cm是各处理根量值（根质量、根体积、根长密度）最大的土层,也是根系活动最为旺盛的区域;土壤水氮适宜（WckNck）时,表层根量增加;水氮过多会导致根系生长受抑（W2N2）,根系活力下降,根系衰亡提前,影响水分吸收,导致水分、氮素利用率低且产量下降;水氮亏缺（W1N1）虽然有助于提高小麦水分、氮素利用率,但产量较低;土壤水分严重缺乏（W0N0）,根系吸水困难,对表层土壤根系数量的增加不利,导致减产。建议在水资源相对充沛条件下滴灌小麦采用WckNck处理,更有利于实现节水、节肥和高产统一。

英文摘要：

Field experiment was conducted to study the spatial and temporal distributions of spring wheat roots,water use efficiency,nitrogen use efficiency and yield under drip irrigation in the arid region of Xinjiang,with the spring wheat cultivar Xinchun19 as test material.There were four irrigation amount treatments in the fixed field trail,including no irrigation（W0）,1 500m^3/hm^2（W1）,4 500m^3/hm^2（W2）and3 750m^3/hm^2（Wck）and four fertilizing amount treatments,including no fertilizing（N0）,150kg/hm^2（N1）,450kg/hm^2（N2）,300kg/hm^2（Nck）.The experiment detected the vertical distribution and dynamic change of root length density,root volume,root weight of wheat in 0-100cm soil depth at jointing stage,heading stage,flowering period and mature period.The results showed that the largest amount of root characteristics（root weight,root length density and root volume）was found at 0-20cm soil depth,which was the most active region for wheat root system.Total amount of root system in the surface layer was increased in the appropriate soil moisture and nitrogen（WckNck）.But excessive water and nitrogen amounts（W2N2）inhibited the growth of root systems,reduced the root activity and the absorption amount of water and nitrogen,and caused lower water and nitrogen use efficiencies and yield for wheat.Although low irrigation and nitrogen amount（W1N1）enhanced water and nitrogen use efficiencies under dry conditions,the wheat yield was lower.An acute shortage of water and nitrogen（W0N0）caused hard water and nitrogen absorption,lowest yield and root number also decreased at surface layer of soil.Therefore,it was better to use WckNcktreatment at the condition of abundant water and nitrogen resources to realize the unity of water and nitrogen saving and high yield.