Identification of Capsicum species using SNP markers based on high resolution melting analysis.

Single nucleotide polymorphisms (SNPs) derived from both nuclear and cytoplasmic DNA sequences were developed to identify distinct species of Capsicum. Species identification was achieved by detecting allelic variations of these type of markers via high resolution melting analysis (HRM). We used the HRM polymorphisms of COSII markers and the Waxy gene from the nuclear sequence, in addition to the intergenic spacer between trnL and trnF from cytoplasmic DNA as our SNP markers. A total of 31 accessions of Capsicum, representing six species, were analyzed using this method. As single markers were insufficient for identifying Capsicum species, combinations of all markers unambiguously identified all six. A phylogeny based on the SNP markers was consistent with the current taxonomy of Capsicum species. These observations demonstrate that the markers developed in this study are useful for rapid identification of new germplasm for management of Capsicum species.