以桐乡大面积应用的常规晚粳稻秀水134、秀水14和嘉67为材料,研究了不同叶龄和株距对机插常规晚粳稻产量及其构成、群体茎蘖动态的影响。结果表明,随着移栽叶龄的延长,有效穗数和总颖花量显著下降,每穗粒数和千粒重显著上升,结实率不同处理间差异不显著。3.0叶龄处理下机插常规粳稻产量最高（9.73 t/hm²）,比3.5叶龄和4.0叶龄处理分别高5.99%和15.14%。随着密度降低,有效穗数、总颖花量及千粒重均显著下降,而每穗粒数增加不明显。14 cm株距处理下机插常规粳稻产量最高（9.34 t/hm²）,比16 cm和18 cm处理分别高2.86%和10.66%。综合来看,在桐乡常规晚粳稻作机插栽培,以3.0叶龄移栽、行株距30 cm×14 cm为宜。

Using conventional late japonica rice Xiushui 134, Xiushui 14 and Jia 67 as materials, which were widely used in Tongxiang City, the effects of different leaf age and plant spacing on the yield and composition and the dynamics of stems and tillers of conventional late japonica rice were studied. The results showed that, the number of effective panicles and total spikelets decreased significantly, the number of grains per panicle and the thousand-grain weight increased significantly, and there was no significant difference in seed setting rate among different treatments with the extension of the transplanted seedling age. The yield of machine-transplanted conventional japonica rice at 3.0 leaves treatment was the highest（9.73 t/hm²）, which was 5.99% and 15.14% higher than 3.5 leaves and 4.0 leaves treatments, respectively. With the decrease of planting density, the number of effective spikes, total spikelets and 1000-grain weight all decreased significantly, while the number of grains per spike did not increase significantly. The average yield of machine-transplanted conventional japonica rice（9.34 t/hm²） under the 14 cm plant spacing treatment was the highest, which was 2.86% and 10.66% higher than that of the 16 cm and 18 cm treatments, respectively. In conclusion, the seedling age of 3 leaves with 30 cm×14 cm spacing seems to be the optimal seedling age and planting density for machine-transplanted conventional japonica rice.