In this research, filed experiments in Tianshui (original planting area) and Lanzhou (extending northern area), Gansu province, with 50 winter varieties of B.napus rapes from domestic and international resources, were conducted to study the adaptation and the physiological and biochemical characteristics of the winter Brassica napus. The following indexes were included in this analysis including catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) activities, malondialdehyde (MDA), soluble protein (SP) contents, and photosynthetic parameters during the pre-winter cold acclimation stage. The results showed that the wintering rate of varieties (lines) tested in Lanzhou was decreased largely compared to that in Tianshui, which suggested that Tianshui was the north boundary of winter rape planting. Some growth morphologies of winter rapeseed seedlings were changed. 78% of leaf color of varieties (lines) were deepened, 52% of the petiole length of varieties (lines) became shorter, and the number of cleft leaf pairs of most varieties (lines) went increased from 1-2 to 3-4. Gs and Ci of leaves were decreased by 1.54% and 60.53% on average, respectively, while Tr was increased by 44.27% with low temperature treatment. Pns of different varieties (lines) varied significantly. The protective enzyme activities, soluble protein and MDA contents of the varieties tested in Lanzhou were increased compared to those in Tianshui, and the average increases were 29.37% and 48.82%, respectively. Through correlation analyses, it was found that there were significant positive pairwise correlations among the POD activity, soluble protein content and the wintering rate, and a negative correlation between MDA content and the wintering rate. |