Identification of Low Temperature Tolerance and Germplasm Screening in Germinating Stage of Vegetable Soybean

Soybean seed germination period is easily affected by low temperature conditions, resulting in poor quality of seedling emergence, and then affect the yield and quality of soybean.To compare the resistance of different vegetable soybean varieties under low temperature stress, this study selected 18 vegetable soybean varieties as materials, and carried out 15 ℃ constant low temperature treatment in the germination stage.We measured the phenotypic indexes and antioxidant enzyme activities under different low temperature stress, and then comprehensive evaluated the low temperature tolerance of vegetable soybean of the varieties in the germination stage with membership function method.The results showed that the low temperature tolerance of 18 vegetable soybean varieties was significantly different under the low temperature stress of 15 ℃.The germination energy and germination rate of Liaoxian, Shenxian 15, Youxisan and Chunpengtezao were greater than 95%, with high antioxidant enzyme activity and low MDA content.Higher antioxidant enzyme activity could help protect them from the damage of reactive oxygen species and alleviate the damage of its own stress, so they had a strong low temperature tolerance.The germination energy and germination rate of Shounong 8, Shenxian 3, Chunfengzaozaoshu 60, Xinfutezao, Xinxian 1 and Longquanshenjian were relatively low, indicating that its seeds germinated slowly or did not germinate under low temperature environment, the germination was inhibited, and they had weak low temperature tolerance.The low temperature tolerance of other vegetable soybean varieties were moderate.