Abstract:

Molecular marker analysis can be used to quantify diversity of Chinese and introduced soybean germplasm and can provide useful information for the relationship of these materials. The genetic diversity of 32 Chinese varieties and 40 foreign ancestral cultivars were investigated by 22 SSR markers. One hundred and seventy alleles were detected, with an average of 6.0 and 6.9 in Chinese and foreign materials, respectively. The polymorphism information content (PIC) was 0.71 in both populations, which indicated a relatively high genetic diversity. There were 48 specific alleles in foreign materials and only 22 in Chinese varieties. The frequency of the alleles in common was very different in the two populations. Great differentiation was also observed between the two populations when UPGMA cluster analysis was used. We analyzed the pedigree of 5 Chinese cultivars derived from two introduced soybean cultivars, Amsoy and Tokachi nagaha, and found 23 specific alleles from foreign materials. The reserved specific alleles were different in each genetic background, and 29.13% specific alleles were reserved in total. This indicated that the introduction of foreign materials in Chinese soybean breeding increased the soybean genetic diversity. For foreign materials, more specific alleles have not been used yet, and should be used as parental materials in elite lines breeding in the future to enlarge the genetic bases of Chinese soybean.

Key words: Soybean, Cultivars, Soybean germplasm introduction, Genetic contribution