Abstract: 【Objective】 The purpose of this project is to study the dynamics and rules of source sink characteristics and yield formation of spring wheat in drip irrigation under nitrogen-fixing cultivation and to propose a stable and high-yielding population structure control index in order to seek the best nitrogen application rate.【Method】Five nitrogen fertilizers gradients were set up in this experiment: Xinchun 31 (high pole) and Xinchun 6 (short pole), 300 kg/hm² (N1) and 275 kg/hm², 250 kg/hm² (N3), 225 kg/hm² (N4) and no nitrogen fertilizer (N5).【Result】The results showed that the quality of 275 kg/hm² (N2) and 250 kg/hm² (N3) populations was the best under the treatments of N application and Xinchun 6, The rate of LAI at the booting stage reached 7.7 and 6.8, respectively, and the ratio of grain number to leaf and grain weight to leaf also reached 4,215.8 seeds/m², 199 g/m² and 4,233.2 seeds/m², 203.9 g/m². The contribution rate of post-anthesis dry matter accumulation to yield also reached 75.04% and 75.52% respectively. The highest yield of N2 was obtained in New Year 31, which was 3.5%-37.7% higher than that of other treatments. The highest yield of N3 was obtained in Xinchun 6, which increased by 2.5%-33.5% compared with other treatments. Through the path analysis of yield components, the combination of 1,000-grain weight and grain number per spike had the greatest effect on the yield of Xinchun 31 and Xinchun 6, respectively, with coefficients of 0.755,9 and 0.525,2. After the nitrogen application rate and the yield were fitted, it was found that the yield reached the highest when the nitrogen application rates reached 286 and 258 kg/hm².【Conclusion】In this experiment, nitrogen fertilizer was reduced by 300 kg/hm² (N1) in high-yield nitrogen crops in wheat fields in Xinjiang. The results showed that the amount of nitrogen fertilizer applied in the treatment of Xinchun 31 was 275 kg/hm²(N2). Xinchun 6 was 250 kg/hm²(N3) significantly improved the wheat population structure. Therefore, it can be shown that appropriate reduction of nitrogen can optimize population structure to achieve high yield, but for different types of varieties, nitrogen application rates suitable for local cultivation conditions should be selected.

Key words: spring wheat; reduction of nitrogen application; population structure; yield; drip irrigation

摘要： 【目的】研究减氮栽培模式下,滴灌春小麦群体源库特征及产量形成的动态及规律,分析与产量目标相结合的高产稳产滴灌春小麦群体结构调控指标,寻求滴灌小麦最佳施氮量。【方法】供试品种为新春31号(高秆)和新春6号(矮秆),5个减氮梯度为300(N1)、275(N2)、250(N3)和225 kg/hm²(N4)和不施氮肥(N5)。【结果】在不同施氮量处理下,新春31号与新春6号分别在275 kg/hm²(N2)和250 kg/hm²(N3)群体质量表现为最优,茎蘖成穗率分别达到了79.19% 和75.91%,孕穗期LAI也达到7.7和6.8,粒数叶比与粒重叶比也分别达到了4 215.8粒/m²、199 g/m²和4 233.2粒/m²、203.9 g/m²,花后干物质累积对产量的贡献率分别达到75.04%和75.52%。新春31号以N2的产量最高,比其他处理提高了3.5%~37.7%;新春6号以N3的产量最高,比其他处理增产了2.5%~33.5%;对产量构成进行通径分析,新春31号和新春6号分别以千粒重和穗粒数对产量的综合作用最大系数为0.755 9和0.525 2;对施氮量和产量进行拟合,当两品种施氮量分别达到286和258 kg/hm²时产量达最高。【结论】在新疆麦区高产大量投入氮肥300 kg/hm²(N1)的基础上,降低施氮量,研究结果表明,减量施氮处理新春31号275 kg/hm²(N2)与新春6号250 kg/hm²(N3)明显改善了小麦群体结构。因此表明恰当的减量施氮,可以优化群体结构获得高产,但对于不同品种类型,应当选择适宜当地栽培条件的施氮量。

关键词: 春小麦, 减量施氮, 群体结构, 产量, 滴灌