Abstract: Aimed to investigate the effects of air temperature on maize growth and its yield, and to establish a monitoring and evaluation model of maize chilling injury, a ‘sowing by stages’ field experiment with three maize varieties and three sowing dates (early, medium, and late) was conducted in Yushu City of Jilin Province. The seedling growth rate, leaf area index (LAI), biomass, and yield of maize, as well as the air temperature, were observed. The results showed that the growth rate of maize had a close correlation with air temperature. If the mean air temperature raised by 1 ℃, the seedling emergence rate and vegetative growth rate would increase by 17% and 5%, respectively; and if the cumulative temperature increased by 100 ℃·d, the maximum LAI of maize would increase by about 10%, and the maximum biomass and per unit area yield of maize would increase by about 8%. If the mean air temperature in the growth period of maize (the period with daily mean temperature >10 ℃) decreased by 07 ℃, or the active cumulative temperature decreased by 100 ℃·d, the maturing stage of maize would be delayed 7 days, a moderate maize chilling injury would occur, and the biomass and yield of maize would decrease by about 8%. If the mean air temperature decreased by 1 ℃, or the cumulative temperature decreased by 140 ℃·d, the growth stage of maize would be delayed 10 days, severe maize chilling injury would occur, and maize yield would decrease by 10% or more. Under the prerequisite of suitable soil moisture condition, climate warming would be beneficial to the increase of per unit area maize yield in Northeast China.

Key words: Cyanea nozakii, Density, Biomass, Growth, Opening date