Abstract: The chilling tolerance of 14 maize hybrids at germination and seedling growth stage were identified under room temperature and low temperature stress conditions. The relative values of each trait including germination rate, mean germination time, the height of shoot, the length of root, dry weight of shoot and root were used as indexes to assess chilling tolerance. The results show that the dry weight of root of maize hybrids with chilling tolerance didn’t decrease. Maize hybrids were clustered into three groups: chilling tolerance, intermediate chilling tolerance and chilling sensitivity. The chilling tolerance varieties included Zhengdan 958, Jiyuan 1 and Jundan 20, while Jinbei 288 and Gaoyou 1 belonged to chilling sensitivity varieties and the rest were ascribed to intermediate chilling tolerance varieties. The correlation analyses show that the relative values of shoot height, dry weight of shoot and root were suitable parameters for evaluating chilling tolerance.

Key words: maize hybrid, germination and seedling growth stage, chilling tolerance identification