Abstract: In order to reveal the effect of cold damage to rice setting rate, the coldresistant experiment was conducted with artificial climate chamber in Heilongjiang province, four major rice varieties with different coldresistant was selected. The results showed that the setting rate of Kongyu131 was 87% with strongest cold resistance after treatment of 8 days under 15℃, following by Longdao3 and Longdao7, and Kendao12 was 61.5 with slight cold resistant. The temperature of sterile type cold damage of Kongyu 〖JP2〗131 was 15℃〖KG*2〗at heading stage, after the treatment from 4 to 8 days, following by Longdao 3 and Longdao 7（16℃）, and Kendao 12（17℃）. The setting rate of all rice verities reduced to 743% with same accumulated temperature in one day (15℃). So the sterile type cool injury was severe for rice that was consistently in low temperature. Diurnal temperature variation reduced the setting rate from 79.5% to 82.4%, namely sterile type cold damage was weaker than that in normal temperature during partial period.

Key words:  Rice, Artificial climate chamber, Booting and heading stages, Steriletype cold damage, Setting rate