Low-pressure selection for new grape crossings ('Riesling italico' × 'Pinot noir'; 'Riesling italico' × 'Chardonnay')

A breeding programme by intra-specific crossing was set up in 1989, in the experimental Station "Riccagioia" (Lombardia region, north-west Italy), with the aim of getting new varieties mainly for white sparkling wine. V. vinifera L. 'Riesling italico' was used as the female parent, while cv. 'Pinot noir' and cv. 'Chardonnay' were used as males, resulting in two progenies (designated RPN and RCH). 900 and 400 seedlings were obtained from RPN and RCH crossings respectively, and a low-pressure field selection was performed, choosing 50 individuals out of the 1,300, by utilizing as screening criteria vegetative habit, phenology, ripening and health aspects. The selected seedlings were grafted on SO4 rootstock, and the productivity and qualitative grape parameters of the field-grown vines were checked over a 4-year-period (2002- 2005) by multifactorial analysis of variance (MANOVA) and SNK (Student Newman Keuls). DNA fingerprinting (by microsatellite) of the progenies and the parent varieties was performed as well, confirming the parentage. Grapes were vinified at harvest, and the wines were evaluated according to sensory analysis, by processing the main descriptors by the non parametric Friedman test. According to the above mentioned parameters, three new varieties were selected, as follows: RCH10 and RPN33 (both white berry) and RPN26 (red berry), due to a good canopy (RCH10), high acidity and sugar and very low cluster and berry weight (RPN26). RCH10 and RPN33 are interesting for sparkling wine because of the white color, the wider sensorial profile and the highest pleasure indices, as compared to the parents (cv. 'Riesling italico' and cv. 'Pinot noir'). RPN 26 has an unexpected later ripening and a wine color intensity much higher than 'Pinot noir', being suitable for the production of red wines; according to the high-pressure selection tightly connected with the objectives of this breeding program, this genotype would have been excluded in the first step of the selection procedure.