[Responses of spring corn growth and yield in a cold area of China to field warming at nighttime during pre-anthesis stage].

By using the facility for increasing free air temperature, a field experiment was conducted in a cold area of Northeast China to study the responses of the growth and yield of rain-fed spring corn to the field warming at nighttime during pre-anthesis stage. Under the field warming at nighttime, the nighttime temperature in 0-10 cm soil layer increased by 1.7 degrees C, and the soil moisture content had a slight decrease. Nighttime warming advanced the spring corn phenophases obviously, shorted the pre-anthesis phase by 1 day, and prolonged the post-anthesis phase by 1 day. Nighttime warming also promoted the corn seedlings growth and the root length. Comparing with those in un-warming treatment, green leaf area and three-ear-leave area in nighttime warming treatment increased by 13.5% and 14.6%, and the aboveground biomass, grain yield, and 100-grain mass increased significantly by 8.2%, 9.3%, and 7.1%, respectively. It was suggested that the climate warming (especially the nighttime warming) in Northeast China could improve spring corn growth, and directly affect the corn yield.