试验结果表明，播种期对精量穴直播早稻产量、有效穗数、结实率和千粒重影响较大，而对每穗总粒数影响不明显；随播种期推迟，各品种发育阶段均相应推迟，全生育期明显缩短。瑞安地区早稻在4月5-12日直播较为适宜。

The experiment results showed that sowing date had a great effect on yield, effective panicles, seed setting rate and 1000-grain weight, but had no obvious effect on total grain number per panicle of precision hill–drop drilling early rice Zhongzao 39. The development stages were postponed correspondingly, the whole growth periods were obviously shortened with the delay of sowing date. The suitable date of precision hill–drop drilling early rice is April 5-12 in Ruian city.