Abstract:

[Objective] This study was conducted to characterize the drought resistance of alfalfa varieties domestically bred in China and introduced from abroad during germination period, and to select the alfalfa varieties with strong drought resistance. [Method] Polyethylene glycol 6000 （PEG-6000） solutions were used to simulate drought stress on five alfalfa germplasm materials （Xinmu No.4, Zhongmu No.3, Gena, A-17, D-23） at concentrations of 0, 5%, 10%, 15% and 20%, respectively. The control group （CK） was treated with distilled water. The germination indices and drought resistance coefficient of the alfalfa germplasm materials at different PEG-6000 treatment concentrations during germination period were measured, and their drought resistance performance was comprehensively assessed using the membership function method. [Result] The analysis of germination indices as well as the multi-dimensionally and comprehensively evaluation on germination indices by the membership function method demonstrated that Gena had the highest drought resistance during germination period among the tested alfalfa varieties, followed by A-17, Xinmu No.4, D-23 and Zhongmu No.3. [Conclusion] Under PEG-6000 simulated drought conditions, the alfalfa variety with the best comprehensive drought resistance was Gona, followed by A-17.

Key words: alfalfa, seed germination, drought resistance, membership function, PEG-6000