以杂交晚粳稻甬优8号、常规粳稻武运粳19为材料，在机械化精量直播方式下，研究了不同播量对其产量及物质生产的影响。结果表明，每667 m2播种量甬优8号1.5~2.2 kg、武运粳19号2.2~3.0 kg处理的产量最高；其群体均能于有效分蘖临界叶龄期够苗，拔节期达高峰苗，且数量适宜，最终成穗率较高（75%左右）；最大叶面积指数均出现在孕穗期，数值适宜；抽穗后干物质积累多，成熟期生物学产量高。

Effects of different sowing rate on yield and dry matter production for mechanical precise-quantity direct seeded rice were studied using japonica rice Yongyou 8 and Wuyunjing 19 as materials. The results showed that the yield of 1.5~2.2 kg/667 m2 sowing rate （Yongyou 8） and 2.2~3.0 kg/667 m2 sowing rate（Wuyunjing 19） were highest than other treats. The population of stems and tillers of which achieved the expected number punctually at the critical leaf-age for productive tillers, and reached the peak with an appropriate value, ultimately arrived at a higher ratio of productive tillers to total tillers. Their maximal LAI appeared at the booting stage and the values were appropriate. The dry matter accumulation of both two models were remarkably higher than others from heading to maturity. The numbers of dry matter accumulation of 1.5~2.2 kg/667 m2 sowing rate （Yongyou 8） and 2.2~3.0 kg/667 m2 sowing rate （Wuyunjing 19） were highest in maturity.