Abstract
Soybean is one of the most important food crops, breeding salt-tolerant soybean varieties is of great significance to alleviate soybean shortage. In this study, the F-box protein family homologous gene GmFBX322 was cloned from the soybean variety Williams 82 and overexpressed in the Shennong 9 soybean variety to further study and explore the physiological mechanism of soybean salt tolerance. GmFBX322 was constructed on the vector pTF101:35S, and integrated into the genome of Shennong 9 soybean variety by Agrobacterium EHA101-mediated cotyledonary node transformation technology, and 4 overexpressed transgenic lines were obtained, molecular assays were performed on the transformed plants. The expression of GmFBX322 was detected by qRT-PCR and it was found that the leaves of the 4 transgenic lines increased by 2.49, 2.46, 2.77, 2.95 times compared with the wild type; after salt treatment for 12 hours, it was found that the expression of wild type Shennong 9 Inducible expression of GmFBX322. After 72 hours of salt treatment, the leaves of wild-type Shennong 9 soybean plants showed obvious wilting and chlorosis, while the leaves of GmFBX322 plants overexpressing GmFBX322 showed no obvious changes. The leaves were taken at 0, 6, 12, 24, and 48 hours of salt stress to determine the antioxidant activity. Ability and osmotic adjustment level, etc. The results showed that the catalase activity in the leaves of the transgenic lines 2265, 2267, 2269, and 2271 was 2.47, 2.53, 3.59, 2.96 times that of the wild-type plant after 48 hours of salt treatment; the soluble sugar content was 1.22, 1.14, and 1.22 of the wild-type plant. 1.14, 1.57 times; the proline content is 2.20, 1.83, 1.65, 1.84 times of the wild type. After comparing the physiological indicators determined by the experiment, the transgenic lines performed better than the control group, indicating that overexpression of GmFBX322 can enhance the salt tolerance of soybean plants. To verify the function of GmFBX322 gene related to stress resistance, add it to the candidate gene of stress resistance, and provide scientific basis for the selection and breeding of salt-tolerant varieties.