MICROSATELLITE MARKERS DISTINGUISH HAWAIIAN OHELO FROM OTHER VACCINIUM L. SECTION MYRTILLUS SPECIES

Abstract

The US Department of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository, Corvallis, collection of Vaccinium L. contains >1700 accessions representing 66 species from 33 countries. About 377 accessions belong to 10 species of Vaccinium section Myrtillus. This section is restricted to the Northern Hemisphere where its primary center of diversity occurs around the Pacific Rim in high elevations from Alaska to Guatemala and in mountains of Japan, Kurile, Sakhalin, and Hawaiian Islands, and Russian Siberia. The first objective of this study was to use microsatellite or simple sequence repeat markers (SSR) previously isolated from domestic blueberry, to uniquely identify three clones of Ohelo berry, V. reticulatum, selected for their ornamental qualities. The second objective was to evaluate the SSR markers for cross-transference to other species within Section Myrtillus including: two genotypes from another endemic Hawaiian species, V. calycinum; 17 representatives from seven North American species (V. caespitosum, V. deliciosum, V. membranaceum, V. myrtillus, V. ovalifolium, V. parvifolium, and V. scoparium), and in two accessions of V. praestans from Sakahlin Island, Russian Federation and one genotype from Hokaido, Japan. As many as eighteen microsatellite markers cross-amplified and appeared polymorphic in most of the genotypes evaluated. The three V. reticulatum genotypes were uniquely identified with eight SSR primer pairs. UPGMA clustering based on nine microsatellite primer pairs clearly separated the Hawaiian taxa and grouped V. praestans together. Two accessions of V. myrtillus (V myrt 1684-1, V myrt 1684-3) collected from within the Kalmiopsis Wilderness of southern Oregon had identical fingerprints indicating a clonal relationship. Conserved primers that amplify what appear to be single loci SSRs are recommended for population genetic analyses in diploid Vaccinium section Myrtillus taxa including V. calycinum, V. reticulatum, V. scoparium and V. praestans. SSR-based analysis indicated high diversity in other taxa of section Myrtillus and the need for a larger amount of accessions from each species, additional markers or sequence-based markers, for taxonomic resolution.