Identification of Quality Characters and Screening of Excellent Germplasm of Soybean from Different Sources in Autumn Sowing in Jiangxi Province

In order to deeply explore excellent soybean germplasm resources, 1 897 soybean germplasm resources from different sources were sown in autumn in Jiangxi Province, and the contents of crude protein and crude fat were comprehensively analyzed and evaluated to screen excellent germplasm, so as to provide a material basis for the breeding of new high-quality soybean varieties and germplasm innovation in Jiangxi Province and soybean producing areas in southern China. The results showed that the crude protein content of soybean germplasm from different sources was relatively high, with an average content of 43.05%. The average value ranged from large to small was: Southern＞Huang-Huai-Hai region＞Northern＞Foreign, and the genetic variation coefficient ranged from large to small was: Foreign＞Huang-Huai-Hai region＞Northern＞Southern, but none exceeded 5%. The overall level of crude fat content was low, with an average content of 18.1%. The order of average value was: Foreign＞Northern＞Huang-Huai-Hai region＞Southern, and the genetic variation coefficient from large to small: Foreign＞Huang-Huai-Hai region＞Northern＞Southern. The degree of genetic variation of foreign soybean germplasm quality traits was more abundant than that of Chinese soybean germplasm. The variance analysis showed that the crude protein and crude fat contents of soybean germplasm in foreign countries, Huang-Huai-Hai region, northern and southern China were significantly different. The maximum frequency of crude protein content ranged from 43.01% to 44.00%, and the maximum frequency of crude fat content ranged from 17.01% to 18.00%. The mean crude protein content was in the maximum frequency range, while the mean crude fat content was slightly higher than the maximum frequency range. According to the distribution characteristics of crude protein and crude fat content of soybean germplasm from different sources, nine excellent germplasm with crude protein content above 48% and eleven excellent germplasm with crude fat content above 21.5% were screened out, among which, Saikai 20 crude protein content was as high as 51.46%, Ls18 crude fat content was as high as 22.18%. It can be used as the backbone parent and donor for soybean quality breeding and soybean protein and fat content-related gene excavation and function research.