Molecular identification of sweet potato accessions using ARMS-PCR based on SNPs

The sweet potato (Ipomoea batatas [L.] Lam.) is the sixth-most important crop in the world following rice, wheat, potato, maize, and cassava. Four varieties (‘Beniharuka’, ‘Annobeni’, ‘Pungwonmi’, ‘Hogammi’) and their Japanese cultivars are broadly distributed in South Korea. In the Korean marketplace, sweet potatoes are classified by color and shape, not by variety, making it necessary to differentiate varieties for uniform production and consumption. In this study, molecular markers were developed to distinguish the four varieties of sweet potato using SNPs and genotyping-by-sequencing (GBS) analysis via a tetra-primer amplification refractory mutation system (ARMS)-PCR. The results revealed that three variety-specific fragments (164 bp and 241 bp of SNP 04-27457768 and 292 bp of SNP 03-16195623) were amplified in the ‘Beniharuka’, ‘Pungwonmi’, and ‘Annobeni’ sweet potato varieties. There were instances where some varieties produced three bands within the gel electrophoresis, indicating heterozygosity at the given SNPs loci. DNA sequencing analysis also confirmed the results of electrophoresis at the SNPs loci. Overall, these molecular markers would provide a useful, rapid, and, simple evaluation method for the Korean sweet potato marketplace, where the mixing of varieties is a serious issue.