Herbicide reduction through the use of weedmat undervine treatment and the lack of impact on the aromatic profile and volatile composition of Malbec wines.

Viticultural practices to control the undervine environment have relied on chemical herbicides. Herbicides usage has resulted in resistance by weeds, alterations in soil environments, as well as not meeting the needs of the organic market. Consequently, black and white weedmat was utilized to manage the undervine area over multiple vintages and its influence on the resultant wines examined. Apart from a difference in juice soluble solids, there was no impact on grape yield. In the 2017 vintage, black weedmat wines had the largest variation in aromatic profile when compared to control; additionally white weedmat was more closely related to the control. These differences had disappeared in the 2018 vintage with all wines having similar aromatic profile concentrations. Trained sensory panel could not discriminate treatment effects on wine flavor and aroma for either vintage. Ultimately, these findings support the use of weedmats in the viticulture setting to eliminate herbicide usage.

Climate change impacts and adaptive strategies: lessons from the grapevine.

The cultivation of grapevines for winemaking, known as viticulture, is widely cited as a climate-sensitive agricultural system that has been used as an indicator of both historic and contemporary climate change. Numerous studies have questioned the viability of major viticulture regions under future climate projections. We review the methods used to study the impacts of climate change on viticulture in the light of what is known about the effects of climate and weather on the yields and quality of vineyard harvests. Many potential impacts of climate change on viticulture, particularly those associated with a change in climate variability or seasonal weather patterns, are rarely captured. Key biophysical characteristics of viticulture are often unaccounted for, including the variability of grapevine phenology and the exploitation of microclimatic niches that permit successful cultivation under suboptimal macroclimatic conditions. We consider how these same biophysical characteristics permit a variety of strategies by which viticulture can adapt to changing climatic conditions. The ability to realize these strategies, however, is affected by uneven exposure to risks across the winemaking sector, and the evolving capacity for decision-making within and across organizational boundaries. The role grape provenance plays in shaping perceptions of wine value and quality illustrates how conflicts of interest influence decisions about adaptive strategies within the industry. We conclude by considering what lessons can be taken from viticulture for studies of climate change impacts and the capacity for adaptation in other agricultural and natural systems.

Pinot Noir wine composition from different vine vigour zones classified by remote imaging technology.

The relationship between grapevine vigour and grape and wine composition was investigated in this study. Own-rooted Pinot Noir grapevines were grown in a commercial vineyard in Tasmania, Australia, with uniform vineyard management practices. Vine vigours were determined by plant cell density (PCD) obtained from aerial photography. As vine vigour decreased, total soluble solid in grapes, total phenolics and anthocyanins in wines increased, while titratable acidity and yield decreased. Wines from the ultra low vine vigour zone had the highest concentrations of esters and alcohols. Higher level of linalool, nerol, geraniol, vitispirane, and ß-ionone were observed in ultra low vigour and low vigour zones, but there was no obvious trend for citronellol and ß-damascenone. Principal component analysis and discriminant analysis of the volatiles illustrated the differences among wines from the four vine vigour zones.