Abstract: According to the division of geographic area, choosing observation data of early rice yields, percentage of output decrease, yield structure and corresponding high temperature parameter namely continuous days of daily mean temperature over 30 ℃ and daily maximum temperature over 35 ℃ from 9 representative meteorological stations at county-level from 1981 to 2015, and using the method of path coefficient analysis, the impacts of high temperature induced heat damage on percentage of output decrease and yield structure of early rice were quantitatively analysised. The results showed that the probability of high temperature stress in early rice in Jiangxi Province was about 80%, which was 30% when the percentage of production was reduced by more than 3%, and the daily maximum temperature had a greater impact than the daily average temperature. The high temperature duration significantly affected the 1 000-grain weight, empty shell rate, and unfulfilled grain rate of early rice. Except for the 1 000-grain weight, which was affected by the daily maximum temperature in southern and eastern rice, the daily average temperature of the rest of the region had a significant impact on the rice yield composition.

Key words: early rice, percentage of output decrease, yield structure, high temperature induced heat damage, quantitative analysis