The modification of cultural practices in grapevine cv. Syrah, does it modify the characteristics of the musts?

Hanseniaspora spp. are one of the most common yeast isolates in vineyards and wineries and play an important role in wine-making.

Saccharomyces cerevisiae, as the workhorse of alcoholic fermentation, is a major actor of winemaking. In this context, this yeast species uses alcoholic fermentation to convert sugars from the grape must into ethanol and CO2 with an outstanding efficiency: it reaches on average 92% of the maximum theoretical yield of conversion. Moreover, S. cerevisiae is also known for its great genetic diversity and plasticity that is directly related to its living environment, natural or technological and therefore to domestication. This leads to a great phenotypic diversity of metabolites production.

Ellagitannin, anthocyanin and woody volatile composition of Cabernet Sauvignon wines aged in oak barrels for 12 months was evaluated. Depending on the container where malolactic fermentation (MLF) was carried out, two wine modalities were investigated: wines with MLF carried out in stainless steel tanks and barrel-fermented wines. Three toasting methods (medium toast, MT; medium toast with watering, MTAA; noisette) were considered for ageing of each wine modality. Sensory analyses (triangle and rating tests) were also performed. Two-way ANOVA of the raw experimental data revealed that the toasting method and the container where MLF took place, as well as the interaction between both factors, have a significant influence (p < 0.05) on ellagitannin, anthocyanin and woody volatile profiles of Cabernet Sauvignon wines.

Flavescence dorée, a serious threat to grapevine cultivation in several European Countries, is caused by phytoplasmas in the 16Sr-V ribosomal group, classified as quarantine organisms in the EU and transmitted mainly by the insect vector Scaphoideus titanus. The disease is controlled only by indirect and preventive measures, with important economic and environmental concerns. Genetic resources from the great variety of Vitis vinifera germplasm together with application of new genomic techniques could be applied to produce resistant/tolerant plants, once the genetic bases of susceptibility are elucidated. In a current Italian project (BIORES*) we are evaluating different international and local grapevine cvs. as well as microvine plants for their response to FD transmission and multiplication in controlled conditions.

Vineyards are home to a myriad of microorganisms that interact with each other and with the vines. Some microorganisms are plant pathogens, such as the oomycete Plasmopara viticola, causing grapevine downy mildew. Others have a positive effect on vine health, such as disease biocontrol agents. These beneficial plant-microbe and microbe-microbe interactions have gained more attention in recent years because they could represent an alternative to the use of fungicides in viticulture.