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As in any other plant, in the grapevine roots play a vital role in terms of anchorage, uptake of water and nutrients, as well as storage and production of chemicals. Their behaviour and development depend on various factors, namely rootstock genetics, soil physical and chemical features, field agronomic practices. Canopy management, involving techniques such as defoliation and pruning, could greatly influence root growth. To date, most of the studies on grapevine winter pruning have focused on the effects on yield and quality of grapes, achievable by using different pruning systems and techniques, while the knowledge of root distribution, development, and growth in relation to winter pruning is still not well understood. In this contest, the purpose of this study was to investigate the effect of winter pruning on the root system of field-grown Vitis vinifera cv. Pinot Gris grafted onto rootstock SO4. We compared two pruning treatments (pruning-P and no pruning-NP) and analysed the effect on root distribution and density, root index and on the root sugar reserves. Root data were analysed in relation to canopy growth and yield, to elucidate the effect of winter pruning on the root/yield ratio. Our data indicated that winter pruning stimulated the root growth and distribution without compromising canopy development, while no-pruning treatment produced less growth of roots but a larger canopy. Information regarding root growth and root canopy ratio is important as it gives us an understanding of the relationship between the aerial and subterranean parts of the plant, how they compete, and finally, offers us the possibility to ponder on cultural practices.

A renewed interest in interspecific varieties has recently emerged, due mainly to producers and consumers more aware of organic farming and impact of phytochemicals in the environment. The assessment of 19 European Vitis hybrids was investigated in an area mostly dedicated to viticulture, the North-EasternItaly. Major agronomic traits, yield, quality characteristics and disease resistance were evaluated during a three-year period (2004 to 2006). Wine sensory analyses were performed and compared with international Vitis vinifera varieties. Even though no genotypes resulted adequate for market release, the results obtained confirm the potential importance of hybrids in an “eco-friendly” viticulture and identify the genotypes interesting for further investigation and breeding: GF 138-3 and GA 48-12 showed good agronomic performance, resistance to more grape diseases and high quality wine.

Environmental factors have been acknowledged to greatly influence grape and wine aromas. Among them, the effect of altitude on grape aroma compounds has scarcely been debated in literature available to date. In the present study, we investigated the influence of altitude on grape composition and aroma evolution during ripening of Vitis vinifera L. cultivar Glera grown in Conegliano-Valdobbiadene DOCG area (Italy).The site at highest altitude (380 m above sea level) was warmer than the lowest site (200 m above sea level) and, even with differences in temperature in the range 1.5-2 °C, the impact of the cultivation site on grape ripening and aroma accumulation and preservation was significant. The lowest site demonstrated slower grape ripening, and grapes at harvest accumulated lower amounts of all of the main classes of aroma compounds typical of the Glera variety. Wines produced from the highest site were preferred in tasting trials for their more patent floral notes and elegance.Altitude strongly influences grape ripening evolution and flavour accumulation in the Glera grape, and this result accounts for the different styles in the sparkling wines subsequently produced. Moreover, the present study shows that aroma compound biosynthesis, particularly that of benzenoides, starts before véraison in Glera. © 2016 Society of Chemical Industry.