Polyphenolics, ascorbic acid, and soluble solids concentrations of strawberry cultivars and selections grown in a winter annual hill production system

Abstract

The effects of cultivar, harvest date, and production year on the soluble solids and antioxidant phytochemical levels of 22 strawberry (Fragaria xananassa Buch.) genotypes grown in a winter annual hill (raised bed) production system were investigated. Fruit harvested in Jan. 2003 and 2004 were characterized by low polyphenolic content, but high concentrations of soluble solids and ascorbic acid; whereas fruit harvested in Feb. 2003 and 2004 generally had elevated polyphenolic concentrations, but lower levels of soluble solids and ascorbic acid. Annual variation in soluble solids and phytochemical composition was also observed among nine strawberry genotypes, which was likely attributable to variations in solar radiation and air temperature. 'Earlibrite' was among the highest for soluble solids concentration on three of the four harvest dates, while 'Carmine' was noted for its high phytochemical concentrations across harvest dates and years. The breeder selection 'FL 99-117' emerged as a promising selection in terms of producing fruit with high concentrations of soluble solids and antioxidant phytochemicals.