Phenotypic diversity of wild cranberry (Vaccinium oxycoccos) in Lithuania

Abstract

The natural resources of wild cranberries (Vaccinium oxycoccos) decreased significantly during the Soviet times mainly because of land drainage. A few larger cranberry fields were left undisturbed within the state protected areas. In the years 1995 to 1999 cuttings of ninety-nine clones were collected in the strict nature reserves and planted in the field collection of Kaunas Botanical Garden for further investigation. A detailed characterisation of phenotypic diversity of thirty-four fruiting clones was carried out. Eighteen morphological properties were used for the characterization of the clones. The morphological differences in berry size and berry and leaf shapes, observed among clones in natural habitats, were also confirmed under ex situ conditions. Some new properties, valuable from the economic point of view, were defined; the degree of erectness of flowering shoots, the yield and the berry ripening time. Biochemical investigations revealed that berries of the selected clones did not differ in titratable acidity or the quantity of dry soluble solids but the content of ascorbic acid fluctuated from 10.0 to 19.9 mg/100g. The biggest difference was observed in anthocyanin contents, varying from 12.8 to 109.8 mg/100g. A total of eleven clones with the largest berries (average weight of berry 1.0-1.5 g) and high yields (2-3 kg/m(2)) were selected for long-term conservation in the collection ex situ. These clones are of potential value for breeding as well as for the re-naturalization of harvested peat bogs.