[Representativeness of Northeast China spring soybeans and their genetic diversity at SSR loci]

A total of 283 accessions were selected from the total 3 226 Northeast China spring soybeans, which represented > 80% of the whole based on their qualitative and quantitative traits. The representative samples were analyzed by 61 SSR loci, and a total of 534 alleles were detected, ranging 2 - 16 alleles per locus, with an average of 8.75 alleles per locus. Among the accessions, the Simpson diversity index (SDI) for each locus ranged from 0.406 to 0.886, with a mean of 0.704, which was relatively lower since there were dominant alleles at most of loci in the representative samples. 35 accessions had specific alleles, which distributed among 29 loci. The differentiation coefficient was lower than 9.27% in 61 loci among the three provinces of Northeast China, which might be caused by lots of common alleles shared among these provinces. The genetic diversity in Jilin and Liaoning provinces was nearly equal, but was higher than that in Heilongjiang Province. The landraces of the representative samples at 61 loci had a higher genetic diversity than that of the released cultivars. The genetic diversity appeared within and between the provinces could be used to broaden the genetic base of modern cultivars, and also, the landraces were the major source for soybean breeding because of their high genetic diversity.