Development of an allele-mining set in rice using a heuristic algorithm and SSR genotype data with least redundancy for the post-genomic era

The allelic diversity of a collection of 4046 rice accessions was assessed using 15 neutral SSR markers distributed throughout the genome. A total of 482 alleles were detected; the average allelic richness was 32.1 alleles per locus. Using a heuristic approach, an allele-mining set was successfully developed on the basis of SSR marker data. 162 accessions of the allele-mining set, accounting for about 4.0% of the entire collection, captured all of the alleles (482) retained in the entire collection, which showed 100% coverage of alleles with minimum redundancy. As a result of validation of this heuristic approach using another 14 SSR markers associated with starch, 70% of the total alleles and 83% of the restricted alleles (allele frequency > 0.05%) were captured in this allele-mining set. The results showed that the heuristic approach meets the condition as an allele-mining set even when applied to another specific set of markers related to starch synthesis in the same entire and allele-mining set. The newly developed methodology for developing allele-mining sets can be used in other crop species. By retaining all alleles of the entire collection, this allele-mining set will be useful for future studies on introducing unused useful alleles into elite rice varieties by breeders in the post-genomic era.