Abstract: In order to study the ecological adaptability of japonica rice varieties of plateau in local indica rice planting area of Yunnan province, the growth duration, agronomic characters, economic characters, yield and disease resistance of six plateau japonica rice varieties with good-quality, high-yield, resistance to disease and cold tolerance were analyzed by using Yixiang725（hybrid indica rice variety） as control variety. The results showed that japonica rice varieties of plateau could mature safely, and their growth duration was the roughly same level or slightly less than the indica rice variety controt in local indica rice planting area. There was a significant positive correlation between growth duration and yield. The whole growth duration of japonica rice varieties was between 155 and 161 days, and their yield was between 6 939.0 and 10 374.0 kg/hm². The whole growth duration of Yunjing39 was 161 days, which was similar to Yixiang725. In all tested varieties, the yield of Yunjing39 with good comprehensive properties and strong stress resistance was the highest, and was significantly higher than the hybrid indica rice variety control. According to the results, Yunjing39 was suitable for local indica rice planting area. The yields of Chujing28 and Yunjing26 were 9 738.0 kg/hm² and 9 676.5 kg/hm², which were slightly lower than indica rice variety control, but they had a certain application value in local production.

Key words: japonica rice variety of plateau, indica rice planting area, ecological adaptability, growth duration, yield