Anthocyanin Profiles of Two Subtropical VacciniumSpecies and ‘O’Neal’ Southern Highbush Blueberry

Abstract

VacciniumL., a globally distributed genus, encompasses economically and nutritionally valuable species such as blueberry ( V. corymbosumL. and its hybrids), cranberry ( V. macrocarponA.), bilberry ( V. myrtillusL.), and lingonberry ( V. vitis-ideaL.). There has been a robust growth of blueberry cultivation in the tropical and subtropical regions of the world, such as Central and South America, the Southern United States, Australia, and the Mediterranean. This growth has been enabled by the integration of various wild species such as northern lowbush blueberry V. angustifolium(Aiton), evergreen blueberry V. darrowii(Camp), and rabbiteye blueberry V. virgatum(Aiton) into highbush blueberry breeding programs. Still, numerous under-studied wild Vacciniumspecies have untapped potential for breeding use and local cultivation in diverse climates. The harvest of wild Vacciniumfruit has long contributed to the nutrition of local communities throughout Southeast Asia and the Americas. Our objective was to conduct preliminary investigations into the fruit qualities and anthocyanin profiles of two such under-studied species, V. myrtoides(Blume) and V. floribundum(Kunth), and compare their characteristics to that of the southern highbush blueberry cultivar ‘O’Neal’ ( V. corymbosumhybrid). Over the spring and summer of 2021, we determined fruit size, percent soluble solids, pH, total anthocyanin concentration, and anthocyanin aglycons profiles. The fruit was sourced from the US Department of Agriculture (USDA), National Clonal Germplasm Repository (NCGR) in Corvallis, Oregon. The wild species’ fruit size, soluble solids, and pH were not significantly different from those of ‘O’Neal.’ The total anthocyanin levels for V. floribundum(87.4 mg anthocyanin/100 g frozen fruit) and V. myrtoides(80.4 mg/100 g frozen fruit) were significantly higher than those for ‘O’Neal’ (32 mg/100 g frozen fruit). Anthocyanin profiles were also unique to each species. V. myrtoideshad the most complex profile with eight anthocyanin peaks; V. floribundumhad four peaks ‘O’Neal’ had three. One of the most prominent anthocyanins in blueberries, petunidin-3- galactoside, occurred in ‘O’Neal’ and V. myrtoidesbut was absent from V. floribundum. Del-3-arabinoside was present in both V. myrtoidesand V. floribundumyet absent in ‘O’Neal’. The unique anthocyanin profiles of the two wild species could have value in diversifying the anthocyanins available in cultivated blueberries and deserve further investigation.