Abstract: The effects of exogenous methyl jasmonate on the physiological and biochemical characteristics and the expression of cold-resistant transcription factor in wheat seedlings under cold acclimation were studied with cultivar “Aikang 58”. The test wheat seedlings were set in two groups：the controlled group was sprayed with double distilled water at low temperature of 4℃，and the treated group was sprayed with 100 μmol/L of methyl jasmonate at 4℃ for a week. The physiological and biochemical results showed that the survival rate of wheat seedling treated with 100 μmol/L of exogenous methyl jasmonate was 91%，significantly increased than that of the controlled group. The SOD、CAT and POD activity of the treated group increased 34%、 50% and 14% than that of the controlled group，respectively，the content of soluble proteins increased 30%，and intracellular free proline content increased 14%，while MDA content decreased by 5%. There was a significant difference between the treated group and the controlled group. The quantitative real-time PCR showed that 100 μmol/L of exogenous methyl jasmonate significantly increased expression of cold responsive transcription factors TaCBFⅣd-B4，TaCBFⅢd-B19，TaCBFⅢc-D3，and TaCBFⅢd-D19，and the expression of TaCBFⅣd-B4 was the highest. The results indicated that spraying 100 μmol/L exogenous methyl jasmonate enhanced the tolerance of wheat seedlings to low temperature stress.

Key words: exogenous methyl jasmonate, wheat, low temperature tolerance, physiological and biochemical characteristics, cold-resistant transcription factor TaCBFs