直播水稻分蘖早、分蘖速度快，单株分蘖相对较多，群体较大，分蘖末期至拔节、幼穗分化期往往出现“脱力”现象，引起分蘖成穗率下降，穗型变小。采用常规补施氨肥，因用量不易掌握，经常出现分蘖消退延缓、群体调控失调、茎秆基节拉长、抗倒能力降低等情况，影响产量的进一步 Direct-seeded rice has early tillering, fast tillering speed, relatively large number of tillers per plant, large population, late-tillering stage to jointing, and often appear “de-force” phenomenon during panicle differentiation, causing the panicle rate to decline and the panicle type to become smaller. Conventional supplementation of ammonia fertilizer, due to the amount of difficult to grasp, often delayed retreat tillering, population control disorders, elongation of stem base, anti-down ability to reduce the impact of further production