A statistical procedure to guide the first stages of clonal selection of the « Tinta dei País » variety

Abstract

In this study, we put forward a procedure, based on the analysis of the principal components and cluster analysis, in order to guide the first stages of the clonal selection of the « Tinta dei Pais » variety. The material used is a set of vines from the region of Vega Sicilia, situated on the Duero valley of the Province of Valladolid in Spain. On these vines, we have originally observed eleven variables associated to their production. This study shows that three of these characters : weight of grape per plant, total acidity and weight of pruned wood, summarize a great part of the information that can be drawn from the set of variables. On the other hand, the graphs and tables, elaborated from statistical treatment of the data, provide an excellent synthesis when identifying the most important characteristics of the vines studied. This procedure can be very useful to the breeder, allowing him to reduce considerably the number of variables for analysis in the evaluation of the vines in the first stages of selection. In particular, it is found that the least advantageous vines arc those of either low yield or high total acidity.