High weed infestation and low nitrogen (N) recovery are among the major causes of lower yield in dry-seeded rice (DSR) compared with transplanted rice. The effects of N rate and planting density dynamics on rice productivity and N-use efficiency (NUE) have been extensively studied in transplanted rice. However, information on the combined impact of N rates, weed regimes, and crop plant densities on rice productivity and NUE is very limited in DSR systems. Attaining synchrony between crop demand and N supply is a key in optimizing the tradeoffs amongst environmental pollution, kernel yield, and profit. Experiments were conducted in 2012 and 2013 to assess the impact of weed regimes (partial weedy and weed-free), N rates (0, 100, 150, and 200 kg ha⁻¹), and rice seeding rates (50 and 100 kg ha⁻¹) on crop productivity, N efficiency indices, and synchronization between crop demand and N supply. The seeding rate of 50 kg ha⁻¹ was better when the sunlight was not a limiting factor. The application of 150 kg N ha⁻¹ produced higher yield-contributing attributes and grain yield (5.2–6.6 t ha⁻¹) of rice than 100 (4.7–5.6 t ha⁻¹) and 200 kg N ha⁻¹ (4.9–6.5 t ha⁻¹). The highest physiological efficiency (40–53 kg grain kg⁻¹ N uptake by plants) was achieved at 150 kg N ha⁻¹. Partial factor productivity was higher in the plots applied with 150 kg N ha⁻¹ than with 200 kg N ha⁻¹. The best degree of synchrony between crop N demand and supply was achieved at 150 kg N ha⁻¹. The results of this study suggest that for harvesting better grain yield, DSR crop should be planted using a seed rate of 50 kg ha⁻¹ in combination with 150 kg N ha⁻¹.

与移栽水稻相比，高杂草侵染和低氮 (N) 回收率是干种水稻 (DSR) 产量较低的主要原因。已在移栽水稻中广泛研究了氮肥量和种植密度动态对水稻生产力和氮素利用效率 (NUE) 的影响。然而，在 DSR 系统中，关于氮肥率、杂草状况和作物植株密度对水稻生产力和 NUE 的综合影响的信息非常有限。实现作物需求和氮供应之间的同步是优化环境污染、籽粒产量和利润之间权衡的关键。2012 年和 2013 年进行了实验，以评估杂草状况（部分杂草和无杂草）、施氮量（0、100、150 和 200 kg ha ^-1）和水稻播种量（50 和 100 kg ha）的影响⁻¹) 对作物生产力、N 效率指数以及作物需求和 N 供应之间的同步性。当阳光不是限制因素时，50 kg ha ^-1的播种量更好。150千克Ñ公顷的应用^-1产生更高的产率，有助于属性和籽粒产量（5.2-6.6吨公顷^-1大米）超过100（4.7-5.6吨公顷^-1）和200千克氮公顷^-1（4.9- 6.5 吨公顷^-1 )。 在 150 kg N ha ^-1时达到最高的生理效率（40–53 kg 谷物 kg ^-1 N 被植物吸收）。施用 150 kg N ha ^-1的地块的部分要素生产力高于施用200 kg N ha ^-1的地块. 在 150 kg N ha ^-1时实现了作物氮需求和供应之间的最佳同步程度。该研究的结果表明，为了获得更好的谷物产量，应使用 50 kg ha ^-1的播种量和 150 kg N ha ^-1的播种量来种植 DSR 作物。