对不同海拔条件下高海拔粳稻的产量构成因素进行了比较分析。结果显示，在不同海拔条件下高海拔粳稻产量构成因素的表型及与产量的相关性和通径系数均存在较大差异。在产量构成因素中，结实率（132.39%）、有效穗数（113.78%）对海拔的反应最为敏感，千粒重次之（106.78%），而每穗总粒数（102.29%）则较稳定。造成高海拔粳稻产量下降的主要原因是结实率和有效穗数的下降。因此，可通过选择有效穗数和结实率对海拔反应较为迟钝的品种类型来提高高海拔粳稻的稳产性。

The yield components of high altitude japonica rice in different altitude areas were analyzed. The results showed that the phenotype of yield components and its correlation coefficients and path coefficients with yield were significantly different. The seed setting rate （132.39%）, the effective panicles （113.78%） are more sensitive to latitude, follows by 1000-grain weight （106.78%）, while the total grains per panicle（102.29%） is relatively stable. The main reasons for lower yield of japonica rice at high altitude are mainly due to the decline in seed setting rate and effective panicles. Therefore, we can choose the japonica varieties, which seed setting rate and effective panicles are low sensitive to latitude, to improve the yield stability at high altitude region.