亏缺灌溉对新疆不同品种春小麦产量和氮素利用的影响

The effects of deficit irrigation on the yield and nitrogen utilization of different spring wheat cultivars under drip irrigation in Xinjiang

【目的】在水肥一体化条件下,研究不同生育期不同亏缺灌溉水平对春小麦产量和氮素利用的影响,为优化新疆春小麦水肥管理、提高小麦生产水肥效益提供技术支撑。【方法】于2022、2023年在石河子大学农学院实验站进行了管栽试验和小区试验,灌溉方式为滴灌。采用裂区设计,主区为干旱敏感品种新春22号(XC22)和耐旱品种新春6号(XC6);副区为灌溉处理,设置全生育期充分灌溉对照[CK,土壤湿度为田间持水量(FC)的75%~80%];分蘖期轻度亏缺(T1,60%~65%FC)、中度亏缺(T2,45%~50%FC);拔节期轻度亏缺(J1,60%~65%FC)、中度亏缺(J2,45%~50%FC)5个处理。调查了开花前后春小麦茎鞘、叶、穗及籽粒干物重、氮素含量,及成熟期小麦产量和产量构成因素;计算了花前氮素积累与转运、花后氮素吸收量及氮素利用率。【结果】两品种小麦成熟期植株氮素积累量(166.15~238.87 kg/hm^(2))、成熟期营养器官氮素分配率、各器官花前氮素转运量(21.76~57.66 kg/hm^(2))及其贡献率(14.15%~31.66%)、植株花前氮素转运量(78.67~147.66kg/hm^(2))及贡献率(51.58%~81.11%)均表现为T2、J2处理低于T1、J1,而T2、J2处理下籽粒氮素分配率、植株花后氮素吸收量及贡献率则高于T1、J1。亏缺灌溉处理下,品种XC6各器官氮素积累与分配、各器官花前氮素转运量及贡献率、产量及产量构成因素总体上高于干旱敏感品种XC22。与CK处理相比,T1处理下耐旱品种(XC6)成熟期植株氮素积累量显著提高了9.98%,茎鞘花前氮素转运量及贡献率分别提高了24.06%、18.91%,植株花前氮素转运量及贡献率分别显著提高了19.21%、12.53%,产量显著提高了12.17%,氮素利用率提高了2.25%,氮肥生产效率显著提高了12.16%,氮素收获指数提高了3.71%。而干旱敏感品种XC22的各项指标在4个亏缺灌溉处理下均低于CK。【结论】在新疆灌溉绿洲农业区,分蘖期轻度亏缺灌溉(60%~65%FC)可显著提高耐旱型春小麦花前氮素的积累量和向籽粒的转运,提高氮素利用率和氮素收获指数,并有效提高产量,进而达到节水高产的效果;而干旱敏感型品种不适宜于任何时期的亏缺灌溉。

【Objectives】Exploring the response characteristics of spring wheat cultivars with different drought resistant capacities to deficit irrigation during the growth period,to provide technical support for optimizing water and fertilizer management of spring wheat in Xinjiang.【Methods】In 2022 and 2023,pipe and field planting experiments,with the split zone design,were conducted at the Agricultural College Experimental Station of Shihezi University.The main factor was cultivar,including a drought sensitive cultivar Xinchun22(XC22)and drought resistant cultivar Xinchun6(XC6).The sub-factor was deficit irrigation period,including a full irrigation control(75%−80%of field water capacity)throughout the entire growth period(CK);a mild deficit irrigation(T1,60%−65%FC),and a moderate deficit irrigation(T2,45%−50%FC)during tillering stage,and mild and moderate deficit irrigation during jointing stage(J1,and J2),respectively.At initial and after flowering stage,plant samples were collected for the determination of dry matter and nitrogen content of various organs,and at maturing stage the yield and yield components were investigated.Then the pre-anthesis N accumulation and export,post-anthesis N accumulation,and nitrogen fertilizer use efficiency were calculated.【Results】The N accumulation(166.15−238.87 kg/hm^(2)),vegetative organ N allocation rate,pre-anthesis N export(21.76−57.66 kg/hm^(2))and its contribution to grain(14.15%−31.66%),pre-anthesis total nitrogen export(78.67−147.66 kg/hm^(2))and contribution rate(51.58%−81.11%)of the two wheat cultivars were all lower in the T2 and J2 treatments than in T1 and J1,while the grain N allocation rate,post-flowering N absorption and contribution rate of plants were higher in the T2 and J2 treatments than in T1 and J1.Under deficit irrigation treatment T1 and J1,XC6 was recorded higher pre-anthesis N accumulation,export and contribution rate in various organs,and yield and yield components than XC22.For XC6,compared with CK,T1 treatment significantly increased the pre-anthesis N export and contribution rates by 24.06%and 18.91%in stems and sheaths,and by 19.21%and 12.53%in whole plants,thereby enhanced maturing plant N accumulation by 9.98%and yield by 12.17%,and elevated N use efficiency,fertilizer N production efficiency,and N harvest index by 2.25%,12.16%,and 3.71%.【Conclusions】For drought resistant spring wheat cultivar,mild deficit irrigation at tillering stage(60%−65%FC)is suitable for the accumulation and transportation of nitrogen at pre-anthesis stage,so could improve nitrogen absorption and nitrogen harvest index,and effectively increase yield,and achieve water-saving and high-yield effects.However,deficit irrigation is not suitable for the yield and nitrogen use efficiency of drought sensitive wheat cultivar,regardless drought stress period and intensity.