北疆春麦冬播早熟高产生理机制及调控技术研究

The objective of this study was to investigate the effect of the later the sowing and large variation, the late often encounter the hazard of dry-hot wind, the prominent problem are yields low and unstable of North Xinjiang. The new alternative planting pattern was proposed, which was planting spring wheat in winter, by seeding before winter, the spring wheat in bud state under the soil winter, early emergence and maturity in early spring. In recent years, the production practice has proved the feasible of the planting pattern, which have existed the outstanding problems in the low emergence rate and week seedlings (because wheat bud is covered by snow nearly five months, and restore slow growth and early into seedlings by snow water immersion in early spring), such as a result, that growth and development characteristics and yield formation were different from planting wheat in spring, and it was not established that the cultivation technical system of the earlier maturity and high yield, and affecting the popularization and application of this planting pattern. Based on this, the project focuses on the freezing resistance of bud of spring wheat by overwintering, and moisture resistant mechanism and regulation index in early spring. To explore the rule of growth development process, matter accumulation and allocation features, grain filling and quality characteristics, revealing physiological mechanisms of early maturity and high-yielding. At the same time, to research the key regulation technologies of planting spring wheat in winter of high yield and high efficiency under drip irrigation, and to establish technical notes, in order to provide a basis and technique guidance for wheat planting after cotton harvest is developing to new planting patterns for realizes the increase of yield and profit in North Xinjiang.

针对北疆的棉茬春小麦因早春融雪影响播期晚且变幅大、后期常遇干热风危害、产量低而不稳的突出问题，提出了新型替代种植模式---春麦冬播，即通过临冬前播种，使春麦以种芽状态在土下越冬，早春早出苗，提早成熟。近年的生产实践已证明此种种植方式具有可行性，但其存在出苗率低和弱苗（因小麦种芽在冬季积雪覆盖下休眠近5个月，在早春雪水浸泡中重新恢复缓慢生长而提早成苗）等突出问题，由此导致的其生育特性和产量形成不同于春播小麦，其早熟高产的配套栽培技术体系尚未建立，影响该种植方式的推广应用。基于此，本项目重点研究春麦种芽越冬抗冻、早春抗湿成苗机制及调控指标，探索春麦冬播生育进程规律、物质积累分配特性、籽粒灌浆特征及品质形成特点，揭示其早熟高产的生理机制。同时，研究在滴灌条件下春麦冬播高产高效的关键调控技术，建立技术规范。为北疆的棉茬小麦发展新型种植模式实现增产增效提供理论和技术指导。

本项目针对北疆棉茬春小麦存在冬季积雪量大，早春融雪慢，土壤含水量过大而导致晚播、晚熟，灌浆期常遇干热风危害，产量低而不稳、水肥利用效率不高等突出问题，提出春麦冬播，即春小麦种子以萌动至一叶一心状态越冬，早春利用积雪融水出苗，较春小麦早出苗，提早成熟、节水。本项目系统研究了冬播期对不同春麦品种越冬出苗率和成苗质量的影响、冬播春麦生育特性与产量形成特征、滴灌条件下不同水氮处理组合对冬播春麦产量、品质及水氮利用效率的影响规律、北疆棉茬冬播春麦高产高效配套技术等。研究结果如下：冬播期对春季出苗率无影响。三年平均结果显示，10月下旬至11月上旬播种，其出苗率变幅54.1%-66.5%。乌鲁木齐越冬期日最低温度在-3.56℃～-6.81℃的范围内，出苗率随温度降低而下降，出苗率大幅度降低是发芽期至出苗期遭受严重冻害的结果。冬播小麦出苗率品种间差异显著，在奇台县越冬期4cm土层最低温度为-7.93℃条件下，春性小麦品种平均出苗率（60.30%）显著高于冬性小麦品种（34.18%），宁春系列品种的平均出苗率（60.82%）高于新春系列品种（42.67%）。冬性品种的平均生育期较春性品种长6d且晚熟，新春系列品种的平均生育期（103d）长于农麦和永良系列品种(88d)及宁春系列品种（92d）；冬播较春播早出苗9-15d、早成熟8-11d、延长生育期6-18d。冬播小麦较春播降低总茎数峰值且提前出现。新冬41、新春6号、新春43号的产量较高，为7581.6-7935.6kg﹒hm-2，获得高产的穗数为431.7×104-515.8×104﹒hm-2,穗粒数31.6-36.3,千粒重46.8-52.8g。综合考虑产量、出苗率、成熟期等因素，新春6号、新冬41号、新春43号适合冬播。春麦冬播较春小麦降低籽粒蛋白质含量、沉降值、湿面筋含量，冬播期对小麦籽粒品质指标无影响。北疆春麦冬播适宜的水氮运筹模式为总滴水量为3600-4200m3﹒hm-2、总施氮量为135-210kg﹒hm-2，可获得产量近7500kg﹒hm-2。制定北疆春麦冬播节水高产栽培技术规程，并大面积应用。在越冬条件好的北疆麦区春麦冬播，可以降低干热风危害风险，容易实现小麦早熟节水高产目标。该项目研究成果应用价值大。