2019 ASHS Annual Conference

Blueberries (family ericaceae, genus Vaccinium) thrive in acidic soils (pH 4.2 – 6.5) and exhibit stress, limited grown, and reduced yields when grown in higher pH soils (pH > 6.5). As a consequence, growers must select naturally-acidic soils or use costly soil amendments to produce this specialty crop. Thus, there is interest in developing blueberry cultivars that tolerate higher pH soils. Nevertheless, sources for this trait have not been identified. While local adaptation to higher pH soils has been previously documented in other ericaceous genera, there is little evidence for higher pH tolerance among Vaccinium spp. In this study, we surveyed native soil pH of wild Vaccinium spp. populations in North America. We hypothesized that local adaptation to higher pH soils exists in wild populations of Vaccinium spp. Accessions of V. arboreum Marshall, V. corymbosum L., V. stamineum L., V. ellioti Chapm., V. virgatum Aiton, V. darrowii Camp., and V. myrsinites Lam. with complete passport information in GRIN-Global were studied in silico. Population coordinates were used to gather native soil pH from USDA-NRCS Web Soil Survey. Additionally, soil samples from native Vaccinium spp. populations found in the Florida state park system were analyzed. Vaccinium spp. were found in soils ranging from pH 4.6 to pH 8.2. V. arboreum exhibited greater pH plasticity than other species. These results suggest that local adaptation to higher pH soils exists in this genus, which could be used to breed pH-tolerant blueberry cultivars.