氮肥对粳性和糯性糜子干物质积累和产量性状及氮肥利用效率的影响

为探讨不同粳糯性糜子干物质积累、产量及氮素利用效率对不同供氮水平的响应,本研究通过两年田间试验,以粳性糜子品种陇糜13号和糯性糜子品种陇糜14号为试验材料,设置45(N1)、90(N2)和135 kg·hm^-2(N3)3个供氮水平,以不施氮为对照(CK),研究不同供氮水平下不同粳糯性糜子在开花期和成熟期的干物质积累与转运、农艺性状及产量的变化,分析氮素积累量、氮肥农学利用效率、氮肥偏生产力、氮素利用率及氮肥表观利用效率对施氮的响应。结果表明,随着施氮量的增加,不同粳糯性糜子的地上部各器官干重呈单峰曲线变化,在N₂下,开花期和成熟期糜子的茎秆干重、叶片干重、茎鞘干重和穗干重均显著高于CK(P<0.05);随着施氮量的增加,不同粳糯性糜子的氮肥偏生产力呈降低趋势,而氮素利用效率呈先降低后升高的趋势;N₂可以显著提高不同粳糯性糜子的株高、茎粗、穗长、单穗粒重、千粒重及产量,也可提升氮肥农学利用效率和氮肥表观利用率。两年数据表明,N2(90 kg·hm^-2)下陇糜13号的农艺性状、产量及氮素利用效率均优于陇糜14号。综上,本研究条件下,甘肃省会宁地区糜子的推荐氮肥施用量为90 kg·hm^-2,这对西北地区种植不同粳糯性糜子具有生产指导意义。

Effects of Nitrogen Fertilizer on Dry Matter Accumulation,Yield Traits and Nitrogen Use Efficiency of Non-Waxy and Waxy Broomcorn Millet

A two-year field experiment was conducted to investigate the responses of dry matter accumulation, yield and nitrogen use efficiency of different non-waxy and waxy broomcorn millet varieties to different nitrogen levels. Non-waxy broomcorn millet Longmi No.13 and waxy broomcorn millet Longmi No.14 were used as experimental materials, and 45 kg·hm^-2(N1), 90 kg·hm^-2(N2) and 135 kg·hm^-2(N2) with no nitrogen as control (CK) were set under field condition. The dry matter accumulation and translocation, agronomic traits and yield of non-waxy and waxy broomcorn millet varieties at the anthesis and maturity stages were studied under three different nitrogen supply levels. The responses of nitrogen accumulation, nitrogen agronomic efficiency, nitrogen partial factor productivity, nitrogen utilization efficiency, nitrogen apparent recovery efficiency were further analyzed. The results showed that the dry weight of aboveground organs of different broomcorn millet showed a single peak curve with the increase of nitrogen application rate. The dry weight of stem, leaf, sheath and panicle were significantly higher than those without nitrogen application (P<0.05) under the treatment of 90 kg·hm^-2at the anthesis and maturity stages. The nitrogen partial productivity of different broomcorn millet decreased with the increase of nitrogen application rate, while the nitrogen use efficiency decreased first and then increased. The nitrogen application with 90 kg·hm^-2can significantly improve the plant height, stem diameter, panicle length, grain weight per panicle, 1000 grain weight and yield, and elevate nitrogen agronomic efficiency, nitrogen apparent recovery efficiency of different non-waxy and waxy broomcorn millet varieties. The two-year date showed that the agronomic characteristics, yield and nitrogen use efficiency of Longmi 13 treated with 90 kg·hm^-2were better than those of Longmi 14. For this study, the recommended amount of nitrogen fertilizer for planting different non-waxy and waxy broomcorn millet varieties in Huining area of Gansu Province was 90 kg·hm^-2, which has a guiding significance for planting different non-waxy and waxy broomcorn millet in Northwest China.