Breeding efforts in the American cranberry (Vaccinium macrocarpon Ait.), a North American perennial fruit crop of great importance, have been hampered by the limited genetic and phenotypic variability observed among cultivars and experimental materials. Most of the cultivars commercially used by cranberry growers today were derived from a few wild accessions bred in the 1950s. In different crops, wild germplasm has been used as an important genetic resource to incorporate novel traits and increase the phenotypic diversity of breeding materials. Vaccinium microcarpum (Turcz. ex Rupr.) Schmalh. and V. oxycoccos L., two closely related species, may be cross-compatible with the American cranberry, and could be useful to improve fruit quality such as phytochemical content. Furthermore, given their northern distribution, they could also help develop cold hardy cultivars. Although these species have previously been analyzed in diversity studies, genomic characterization and comparative studies are still lacking. In this study, we sequenced and assembled the organelle genomes of the cultivated American cranberry and its wild relative, V. microcarpum. PacBio sequencing technology allowed us to assemble both mitochondrial and plastid genomes at very high coverage and in a single circular scaffold. A comparative analysis revealed that the mitochondrial genome sequences were identical between both species and that the plastids presented only two synonymous single nucleotide polymorphisms (SNPs). Moreover, the Illumina resequencing of additional accessions of V. microcarpum and V. oxycoccos revealed high genetic variation in both species. Based on these results, we provided a hypothesis involving the extension and dynamics of the last glaciation period in North America, and how this could have shaped the distribution and dispersal of V. microcarpum. Finally, we provided important data regarding the polyploid origin of V. oxycoccos.

PH plays a critical role in regulating nutrient availability and uptake, directly influencing plant growth and productivity. Cranberries grow optimally within a soil pH range of 4.2 to 5.5, but achieving this range remains challenging, even with amendments. This study evaluated the effects of elevated soil pH (7.0 to 7.2) on cranberry cultivation and identified factors contributing to adverse outcomes. Stems, leaves, and fruits were sampled from plants grown in soil with a pH ranging from 4.8 to 7.0. Nutrient composition, fruit size, yield, and anthocyanin content were analyzed. High soil pH levels resulted in significant reductions in fruit size (25–35%) and yield (29–56%). Cranberry plants grown in elevated pH conditions showed a significant (p < 0.001) decline in nitrogen, phosphorus, and potassium, and increased calcium and magnesium in soil, stems, leaves, and fruits. Additionally, photosynthesis and chlorophyll fluorescence were significantly reduced (p < 0.05 to 0.001). Certain amino acids, carbohydrates, and organic acids increased significantly (p < 0.05 to 0.0001) in high pH soils, suggesting a role in stress adaptation. Calcium levels in fruits and shoots were inversely correlated with fruit size and some metabolites. These findings demonstrate that soil pH levels above the optimal range (4.2–5.5) substantially impair cranberry growth and quality by disrupting nutrient balance and photosynthesis. The results highlight the urgent need for improved water and soil management strategies to mitigate high soil pH stress in commercial cranberry production.