| The winter and spring turnip rape parents (Longyou 7, Longyou 9 and Parkland) and their filial generations, significantly differing in cold tolerance and quality, were comprehensively analyzed. Cold tolerance variations were examined on the basis of five physiological indexes and overwintering rates before and after cooling. The results showed that the physiological indexes of all individuals were increased after cooling. The SOD, POD, CAT, soluble protein and MDA values were 131.16～489.50 U·g-1, 8.59～68.44 U·g-1, 2.63～20.85 U·g-1, 2.53～7.80 mg·g-1 and 3.69～13.67 mg·g-1 before cooling, but reached to 290.87～796.88 U·g-1, 22.63～101.5 U·g-1, 8.89～48.30 U·g-1, 4.46～10.68 mg·g-1 and 5.77～21.25 mg·g-1 respectively after the treatment. In addition, physiological indexes and overwintering rates were segregated. The variation of physiological coefficient in F1 generation was small, and the overwintering rates of filial generations of winter turnip rape for female parents (70.27%) were higher than those of the spring parent for the female parent (64.48%). The variations in F2 and BC1 generations were large, and overwintering rates of a group of winter parents for the recurrent parent (71.43%～76.19%) were significantly higher than the groups of spring parents as the recurrent parent (38.46%～43.75%) in BC1. It was further found that significant correlations between the five physiological characteristics and overwintering rates could be identified. Correlation coefficients were 0.597, 0.757, 0.665, 0.567 and -0.663 respectively. In conclusion, it was feasible to analyze cold tolerance characteristics using these physiological indexes, which could reveal the differences of cold tolerance indexes and overwintering rates in different filial generations, and could provide good base materials for quality improvement of winter turnip rape. |