Articles
A MULTI-DISCIPLINARY STUDY OF THE VINEYARD ECOSYSTEM TO OPTIMIZE WINE QUALITY
In general the effects of these factors on grape composition and wine quality is studied separately and therefore the complexity of the vineyard system is not fully appreciated.
It is the authors’ contention, supported by numerous experimental evidences, that it is possible to define an empirical and easy to use model to understand the processes that affect the wine quality.
The balance that vines establish between yield and vegetative growth seems to be useful to explain variation in wine quality, as the evaluation of the source to sink ratio proved to be effective to explain plant physiological behaviour.
It is emphasized that the most important factors of variability in the vineyard (canopy manipulation techniques, cluster shading, soil characteristics, site of cultivation, plant mineral nutrition, cultivar and clone effects), that occur throughout the vegetative season and characterize the site of cultivation, act on vines by modifying the relationships between sources and sinks, specifically leaves and bunches.
The estimation of the relationships between vegetative and productive performances of vines may be successfully linked to the quality potential of the vineyard; though we are still far from a reliable prediction of vineyard response in term of wine quality to the availability of different nutrients, to different soil and meso-climatic conditions or sites.
Intra-clonal variability of the yield to pruning weight ratio, however, is often not significant and, in general, it is not responsible for the wine quality variation among clones.
In the quality definition process, relationships between yield and vegetative growth must be implemented with the description of the interaction between environment and variety or clone, which may determine changes in wine quality due to different ripening processes.
It is concluded that wine quality evaluation by sensory analysis makes it possible to synthesize all the effects of agronomic and genetic factors on the final quality of wine and in this way the complexity of the wine quality model can be approached.