Abstract: Based on the meteorological data of the Jingzhou national meteorological observation station in the past 68 years from 1953 to 2020, the cold dew wind grade index of the main rice varieties was determined, and the occurrence situation and evolution law of the cold dew wind in Jingzhou City were analyzed. Taking 2020 as an example, the effect of cold dew wind on indica rice was analyzed. The results showed that different rice varieties had different resistance to low temperature. The cold dew wind index for indica hybrid rice should be the daily average temperature below 23 ℃ for 3 consecutive days or more, and the cold dew wind index for indica conventional rice should be the daily average temperature below 22 ℃ for 3 consecutive days or more. The earliest cold dew wind could occur in mid-to-late August, and the latest occurred in early October. The frequency of moderate and severe cold dew wind was higher from mid-to-late September to early October. After 2000, the beginning of the cold dew wind was obviously ahead, and the amplitude increased. The cold dew wind in 2020 caused the production reduction of single cropping late rice, shrimp rice, double cropping late rice and ratoon rice to different degrees. From the perspective of safe heading, the safe full heading period of indica conventional rice in Jingzhou City was September 13, and the safe full heading period of indica hybrid rice was September 12. The sowing period of double-season late rice, one-season rice and direct-seeding shrimp rice should be reasonably arranged.

Key words: cold dew wind, indica hybrid rice, indica conventional rice, Jingzhou City