Genetic inferences and breeding implications from analysis of cranberry germplasm anthocyanin profiles

Abstract

A diversity of anthocyanins exists among angiosperm species. Studies indicate that various anthocyanins differ in antioxidant potential, their bioavailability, and stability during processing. The fruit of the American cranberry, Vaccinium macrocarpon Ait., is recognized as having six anthocyanins, composed largely of 3-O-galactosides and 3-O-arabinosides, and to lesser amount (≈6%), 3-O-glucosides of the aglycones cyanidin and peonidin. This study analyzed proportions of these six anthocyanins from >250 accessions of a germplasm collection over harvest dates. Fruit samples from 78 selected accessions, based on the first year analysis, were also analyzed a second year. Principal component analysis identified general negative relationships between the proportions of cyanidin versus peonidin, arabinosides versus glucosides, and galactosides versus arabinosides and glucosides. These relationships were consistent across the 2 years. Most variation in germplasm anthocyanin profiles reflected variation of cyanidin versus peonidin proportions, with cyanidin to peonidin ratios ranging from 3.6:1 to 0.5:1. Variation for glycosylation profiles was also evident, with galactoside proportions ranging from 64% to 75%, arabinoside proportions ranging from 20% to 33%, and glucoside proportions ranging from 3% to 9%. Evidence for both significant qualitative and quantitative genetic variation exists for the methoxylation of cyanidin to peonidin. Significant quantitative genetic variation is also apparent for glycosylation.