Abstract

In this study, the authors systematically evaluated the effect of low temperature stress on the germination of rapeseeds for 39 oilseed rape (Brassica napus L.) varieties. The results indicated a significant variation in the low temperature resistance of the seeds for different rape varieties. Using clustering method, various varieties were divided into different types, among which Huayouza No. 13, Fengyou 5103, Huayouza 95, Huayouza 62 and Fengyou 701 germinated well at low temperatures, while Zhongshuang No. 8 and Zhongshuang No. 11 showed poor germination. Correlation analysis was performed for 18 indices of seed germination, of which any two of germination percentage (GP), emergence percentage (EP), germination index (GI) and seedling vigour index (SVI) had high significant positive correlation, and they were all high significantly negatively correlated to the mean germination time (MGT). The GP was significantly negatively correlated with dry weight (DW). The MGT also showed a negative correlation with the root length (RL) and the total length (TL). The MGT had a statistically significant positive correlation with DW, and a negative correlation with shoot length (SL). Both the GI and SVI were significantly negatively correlated with DW. No correlation was observed between root to shoot length ratio (RL/SL) and any other index.