EVALUATION OF BERRY QUALITY TRAITS IN F₁ PROGENY DERIVED FROM THE CROSS 'MUSCAT HAMBURG' × 'SUGRAONE SEEDLESS' (VITIS VINIFERA)

The common objective of most grape breeding programs is to produce locally adapted, high yielding cultivars with a quality that is suited for the intended use, with special emphasis on the time of ripening, colour, sugar and acid content, special aromas, as well as loose clusters and big berries. In this paper, the berries from a population of 93 plants derived from controlled crosses between the cultivars ‘Muscat Hamburg’ (MH, female progenitor) and ‘Sugraone’ (SS, male progenitor) are characterised. MH berries are dark violet, small and soft, with seeds and an intense muscat taste. On the other hand, SS is a very early maturing seedless cultivar with yellow crispy berries. For the table grape progeny, 93 hybrids were established under production and three replications of each hybrid were collected and evaluated during the 2005 and 2006 seasons. The parameters considered were: total and individual anthocyanin monoglucosides (delphinidin 3-glucoside, cyanidin 3-glucoside, petunidin 3-glucoside, peonidin 3-glucoside and malvidin 3-glucoside), sugars (sucrose, glucose and fructose) and organic acids (tartaric and malic acids). The results were analysed using the Kolmogorov-Smirnov test in order to determine the type of distribution. The parametric Student test and non-parametric Wilconson test were applied to detect the year effect on metabolite concentrations. Spearman and Pearson tests were used for correlation analysis. Glucose, fructose, tartaric and malic acids followed a normal distribution, while total and individual anthocyanins and sucrose followed a non-normal distribution during the two years of study. Significant inter-annual differences were found between the values for the two years for cyanidin-3-glucoside, glucose, fructose, sucrose and malic acid. Finally, statistically significant correlation (p<0.001) between both years was observed for all the parameters, except glucose and fructose concentration.