Identification of five soybean cultivars based on the polymorphism of SSR markers. (a) The distribution of SSR markers in soybean chromosomes; (b) The phylogenetic tree of all soybean plants. White circles represent cv. Hedou 13 (HD13), black dots represent cv. Zhonghuang 13 (ZH13), white triangles represent cv. Zhonghuang 18 (ZH18), black triangles represent cv. Zhonghuang 68 (ZH68), white diamonds represent cv. Zhonghuang 35 (ZH35); (c) The principal component analysis. Red: HD13, blue: ZH13, orange: ZH18, purple: ZH68, black: ZH35. The grey circle indicates the cluster of the cultivar.