Analysis of phenotypic variation of sugar profile in different peach and nectarine [Prunus persica (L.) Batsch] breeding progenies

BACKGROUND: Specific sugar contents are well known for contributing to a range of quality traits of fresh fruits such as flavour, texture and health properties. Peaches and nectarines of 205 genotypes from 14 different breeding progenies cultivated under Mediterranean conditions were evaluated by high-performance liquid chromatography for their content of these sugar traits. RESULTS: A high contribution of cross to the phenotypic variance of all evaluated fruit quality traits was found. There were significant differences in mean sugar concentrations between peach and nectarine, yellow- and white-fleshed or freestone and clingstone genotypes. Pre-selected genotypes from the original breeding programme showed enhanced soluble solid content (SSC), total sugar and sucrose contents. A significant effect of year was found for SSC, sucrose and glucose contents, whereas no effect was found for fructose and sorbitol contents. Individual sugar contents correlated significantly with each other and with other fruit quality traits. CONCLUSION: A significant effect of cross, year and qualitative traits on the sugar profile of peaches and nectarines was found. Moreover, the differences shown in sugar traits between the breeding population and the pre-selected genotypes indicated the importance of sugar profile in the global quality of peaches and nectarines. (C) 2009 Society of Chemical Industry