Abstract:  Northeast China is the main rice producing area in China, and chilling damage is the most serious meteorological disaster affecting rice production in this area. Study on the temporal and spatial distribution of sterile-type chilling damage in the rice growth-suited areas with different maturity is helpful to provide the scientific basis for the rational production and management of rice in Northeast China. Based on the daily mean air temperature data at 167 meteorological stations and rice growth stage record data at 28 phenological observation stations, Chilling Damage Grade of Rice Northern China (GB / t 34967-2017) was selected to evaluate sterile-type chilling damage in the rice growth-suited areas with different maturity in Northeast China. First, the rice growth-suited areas with different maturity at three stages 1986-1995, 1996-2005 and 2006-2015 were determined based on the 80% guarantee rate of active accumulated temperature. Then, the ratio (F) of the meteorological stations with sterile-type chilling damage and frequency (P) of chilling damage were calculated to analyze temporal and spatial distribution of the damage from 1986 to 2015. The results showed that the area unsuitable for rice growth decreased gradually and the rice growth-suited area with different maturity showed an expanding trend towards north and east. Among them, the late-maturating rice area showed the most significant increase. The ratio (F) of the stations with sterile-type chilling damage was the largest in the early-maturating rice area, followed by the late-maturating rice area and midseason-maturating rice area. The occurrence frequency (P) of sterile-type chilling damage varied greatly among stations and rice growth-suited areas with different maturity. During 1986-1995, 1996-2005 and 2006-2015, obvious sterile-type chilling damage mainly occurred in the midseason-maturating, late-maturating and early-maturating rice area, respectively. During 2006-2015, the frequency (P) of sterile-type chilling damage with Sever grade reduced in the early-maturating rice area, while the frequency (P) with Middle grade in the midseason-maturating rice area and Slight grade in the late-maturating rice area increased. It should be noted that sterile-type chilling damage in Northeast China was still uncertain despite the overall decline in frequency, and probably occurred in any area and any year. The fluctuation of sterile-type chilling damage led to the increase of its uncertainty. In the context of climate change, the planting system, disaster prevention and relief measures should be reasonably arranged in combination with the characteristics of sterile-type chilling damage occurrences, so as to reduce its impact on rice yield.

Key words:  Rice, Maturity, Active accumulated temperature, Sterile-type chilling damage of rice, Northeast China