Abstract: High temperature harm at rice florescence was a big problem to rice production in the Yangtze River basin. Average temperature anomaly, the highest temperature anomaly, the frequency and temporal distribution of extra high temperature lasted 3d and 5d in July and August were analyzed respectively with tendency analysis and temperature anomaly analysis, based on observed temperature data from Jingzhou agrometeorological station during 1954-2003. The result showed that the average temperature and the highest temperature in Jianghan Plain did not increased in last 50 years. The frequency of average temperature≥30℃ lasted 3d and 5d, and the highest temperature≥35℃ in July and August increased a little. Extra high temperature weather occurred in the mid and last ten days of July and the first ten days of August in general. High temperature harm occurred more than 100%, and serious high temperature harm occurred 62% from mid of July to first of August. So adjusting rice-planting date and high temperature tolerant breeding to mitigate high temperature harm were recommended in this region.

Key words: Jianghan Plain, Jianghan Plain, Middle-season rice, Florescence, High temperature harm