为明确水分管理方式、施氮量和用种量对水直播稻生长发育特性、产量和苗期稻田杂草发生的影响，于2021年以卓两优1126为试验材料，采用再裂区试验设计，在湖南省浏阳市开展大田试验。以水分管理方式为主区，施氮量为副区，播种量为再副区。水分管理（播种至3叶1心期）设淹水（W1）和湿润（W2）2个处理；施氮量设0 kg/hm²（N0）、150 kg/hm²（N1）和195 kg/hm²（N2）3个处理；播种量设15.0 kg/hm²（D1）、22.5 kg/hm²（D2）和30.0 kg/hm²（D3）3个处理。结果表明，不同水分管理方式间苗期稻田杂草总数差异极显著，而不同施氮量和用种量处理间杂草总数差异不显著。W1处理水稻平均产量为8.5 t/hm²，显著高于W2处理；N1和N2处理间水稻平均产量差异不显著，但均显著高于N0处理；水稻产量随着用种量的增加而增加，但不同用种量处理间差异不显著。综上，水稻淹水直播条件下，施氮量为150 kg/hm²，播种量为15.0 kg/hm²，并于3叶1心期除草1次，可在减少除草剂用量的同时实现水稻增产。

A field experiment was conducted in Liuyang City, Hunan Province in 2021 to explore the effects of water management methods, nitrogen application rate, and sowing rate on direct seeding rice growth and development characteristics, yield, and weed occurrence in rice fields, using Zhuoliangyou 1126 as the experimental material. The experimental design was a split-split-plot arrangement, the main plots had different water management methods (W1, flooding; W2, wetting), the subplots had different nitrogen application rate (N0, 0 kg/hm²; N1, 150 kg/hm²; N2, 195 kg/hm²) and sowing rate (D1, 15.0 kg/hm²; D2, 22.5 kg/hm²; D3, 30.0 kg/hm²). The results showed that there was a significant difference in the total number of weeds under different water management treatments, while there was no significant difference in the total number of weeds under different nitrogen application rate treatments and sowing rate treatments. The rice yield of W1 treatment was 8.5 t/hm², significantly higher than that of W2 treatment. The difference in average rice yield between N1 and N2 treatments was not significant, but both were significantly higher than the N0 treatment. The rice yield increased with the increase of sowing rate, but there was no significant difference between different sowing rate treatments. In summary, under the condition of submerged direct seeding of rice, the nitrogen application rate was 150 kg/hm², the sowing rate was 15.0 kg/hm², and weeding once during the 3-leaf and 1-heart stage could achieve rice yield increase while reducing the amount of herbicide used.