Health benefits of wine industry by-products

A crucial issue associated with the long-term impact of climate change in viticulture concerns the capacity of resilience of the typical varieties currently cultivated in traditional areas. Indeed, regions that are currently characterized by optimal climatic conditions can cease to be so in the future. At the same time, new premium wine production regions may arise north of 50oN. Both these threats and opportunities are based on the assessment of a very likely gradual temperature increase along the 21st century, resulting from the ensemble mean of the state-of-the-art climate projections. Such an assessment is orienting decision-makers and stakeholders to rethink the grapevine cultivation zoning, prefiguring, for each variety, a shift at higher latitudes and/or at higher altitudes areas.

Vineyard floors in warm, dry landscapes including those in South Australia, have traditionally been managed using intensive practices such as tillage and herbicides to control weeds and vegetation, thereby limiting competition with grapevines for water and nutrients in order to not compromise yields.

The mapping of spatial variability in vineyards offers the potential to implement zonal management strategies with the aim to optimize economic benefits and increase sustainability by managing natural resources, such as water used for irrigation, more optimally. This study characterized the (natural) variability in plant water status in a commercial Cabernet Sauvignon block, using remote sensing techniques, and identified the impact of this variability on the yield, and juice and wine composition. From the field data collected over two growing seasons, we demonstrated that remote sensing techniques are a practical and powerful tool for mapping spatial variability within vineyard blocks.

Soil is a reservoir of microorganisms playing important roles in biogeochemical cycles and interacting with plants whether in the rhizosphere or in the root endosphere. The composition of the microbial communities thus impacts the plant health. Rhizodeposits (such as sugar, organic and amino acids, secondary metabolites, dead root cells …) are released by the roots and influence the communities of rhizospheric microorganisms, acting as signaling compounds or carbon sources for microbes. The composition of root exudates varies depending on several factors including genotypes. As most of the cultivated grapevines worldwide are grafted plants, the aim of this study was to explore the influence of rootstock and scion genotypes on the microbial communities of the rhizosphere and the root endosphere. The work was conducted in the GreffAdapt plot (55 rootstocks x 5 scions), in which the 275 combinations have been planted into 3 blocks designed according to the soil resistivity. Samples of roots and rhizosphere of 10 scion x rootstock combinations were first collected in May among the blocks 2 and 3. The quantities of bacteria, fungi and archaea have been assessed in the rhizosphere by quantitative PCR, and by cultivable methods for bacteria and fungi. The communities of bacteria, fungi and arbuscular mycorrhizal fungi (AMF) was analyzed by Illumina sequencing of 16S rRNA gene, ITS and 28S rRNA gene, respectively. The level of mycorrhization was also evaluated using black ink coloration of newly formed roots harvested in October. The level of bacteria, fungi and archaea was dependent on rootstock and scion genotypes. A block effect was observed, suggesting that the soil characteristics strongly influenced the microorganisms from the rhizosphere and root endosphere. High-throughput sequencing of the different target genes showed different communities of bacteria, fungi and AMF associated with the scion x rootstock combinations. Finally, all the combinations were naturally mycorrhized. The root mycorrhization intensity was influenced by the rootstock genotype, but not by the scion one. Altogether, these results suggest that both rootstock and scion genotypes influence the rhizosphere and root endophytic microbiomes. It would be interesting to analyze the biochemical composition of the rhizodeposition of these genotypes for a better understanding of the processes involved in the modulation of these microbiomes. Moreover, crossing our data with the plant agronomic characteristics could provide insights into their roles on plant fitness.

Italy is a rich hub of viticultural biodiversity harboring hundreds of indigenous grape varieties that have adapted over centuries to the diverse climatic and geographic conditions of its regions. Preserving this biodiversity is essential for maintaining a diversified genetic pool, crucial for addressing future challenges such as climate change and emerging plant diseases. Rising temperatures, precipitation pattern variations, and extreme weather events can affect grape ripening, crop quality, and contribute to disease development. Integrated disease management necessitates exploration of novel strategies. Biotechnologies emerge as a significant player in tackling modern viticulture challenges.