Abstract: The impact of climate changes on crops widely attracts people^,s attention, respectively in the cold and arid regions in northern China, so it is necessary to develop a technique for rapeseed production adapting to the warmed climate. Nine cultivars with different levels of resistance to cold were performed in the original growing (Tianshui) region and northern-extending region (Zhangye). Data related to growth and development were determined during growth stages. The results showed that the over-wintering rate of winter rapeseed reduced from 93.0%–100.0% (the original region) to 40.0%–95.0% (the northern-extending region); the growing period delayed from 280–284 days to 287–289 days. The vegetative growth period before wilt leaf stage and the transition stage from vegetative growth to reproductive growth were shortened greatly, while the duration from wilt leaf stage to regreen stage was longer,showing a “short-long-short” growth pattern in northern-extended winter rapeseed. So the plant height and branch length were shortened, and the dry matter weight of northern-extended winter rapeseed was also decreased. The 1000-grain weight and the seeds pee riliqua were higher at Zhangye than at Tianshui. The yield of Tianyou 8 with strong winter resistance decreased from the original regions, 2 518.8 kg ha^–1 to 1 666.5 kg ha^–1; but that of the ultrastrong cultivar Longyou 6 increased from 741 kg ha^–1 to 3 333 kg ha^–1. because winter rapeseed in the northern-extending region grows under poor climatic conditions,Ultra winter-hardy rape cultivars, reasonable sowing date and planting density should be necessary to ensure the high over-winter rate.

Key words: Winter rape Northern-extending region, Growth and development characteristics