Abstract:

【Objective】 The objective of the study was to evaluate waterlogging tolerance of the rapeseed (Brassica napus L.) doubled haploid (DH) population and to screen the most waterlogging-tolerant and waterlogging-sensitive DH lines. 【Method】 For phenotyping, the rapeseed seedlings were grown in plastic pots. Six traits (plant height, root length, shoot dry weight, root dry weight, root/shoot ratio and total dry weight) together with WTC (waterlogging tolerance coefficient) of all the traits were investigated and analyzed. The waterlogging tolerance of the 118 DH lines and their parents were evaluated. 【Result】 The results showed that: the six responsive traits changed significantly under the waterlogging conditions compared with the control in the experiment and the effects of waterlogging were much more severe on RDW than other traits. All of the six traits and WTC of all the traits showed transgressive and continuous distribution under both waterlogging and control conditions. The correlation among all the traits investigated in the study indicated that WTC of SDW, RDW and TDW could be used as available evaluation indices for waterlogging tolerance. 【Conclusion】 Lines 005, 007, and 040 screened from the population are the most waterlogging-tolerant lines and 086, 110, and 119 are the most waterlogging-sensitive lines.

Key words: Brassica napus, seedling stage, waterlogging tolerance, evaluation index