DIFFERENCES IN WINE QUALITY DUE TO CLONE-ENVIRONMENT INTERACTION: THE EXPERIENCE WITH 'NEBBIOLO' IN NORTH-WEST ITALY

摘要

Nebbiolo, one of the most important variety of North-west Italy, is traditionally grown in quite different environments. In addition Nebbiolo population is well known for its genetic variability. The final imprint in term of wine quality is then givenby the combined effect of clone and environmental growing conditions. In order to investigate the influence on wine composition due to this interaction, a trial has been carried out monitoring for three vintages (2004-06) the agronomic and the enological performances of three popular clones of Nebbiolo (142, 308 and 423) grown in four different sites localized in Aosta Valley (Donnas) and Piedmont (Langhe, Lessona and Roero). All the sites are typical areas for the production of Nebbiolo wines but differ considerably for climate, slope and soil. The quality of wines, obtained by small-scale wine-making, was assessed by mean of chemical and sensory analysis. In the mountain district of Aosta Valley, the clonal choice resulted more determinant in the enological response, especially in terms of acidity and colour, and the wines of vigorous and yielding 142 were preferred by sensory panellists. In general all the clonal wines from the favourable environments of Langhe and Roero resulted more structured compared to the ones from other locations, however in these sites the wines of low vigour and low yielding clone 423 got the best score. In Lessona vineyard the environmental influence prevailed on the clonal aptitudes and the wines of the three clones were quite similar.