Genotypic variability in root architectural traits and putative implications for water uptake in grafted grapevine

This study evaluates the effect of different oenological factors and natural mediators on the degradation of Ochratoxin A (OTA) using Botrytis cinerea laccase.

Hydrogen sulfide and methanethiol are recognised as two of the most significant contributors to reductive off-flavours in wine.

Wine longevity is a complex multifactor phenomenon in which the weight of the different factors is not well known. One of the key factors of wine longevity is related to its resistance to oxidation. This property can be defined as the ability of the wine, under an exposure to oxygen, to keep its color, avoid accumulation of acetaldehyde and Strecker aldehydes (SA), and keep as long as

Water is the main limiting factor for yield in viticulture. Improving drought adaptation in viticulture will be an increasingly important issue under climate change. Genetic variability of water deficit responses in grapevine partly results from the rootstocks, making them an attractive and relevant mean to achieve adaptation without changing the scion genotype. The objective of this work was to characterize the rootstock effect on the diurnal regulation of scion transpiration. A large panel of 55 commercial genotypes were grafted onto Cabernet Sauvignon. Three biological repetitions per genotype were analyzed. Potted plants were phenotyped on a greenhouse balance platform capable of assessing real-time water use and maintaining a targeted water deficit intensity. After a 10 days well-watered baseline period, an increasing water deficit was applied for 10 days, followed by a stable water deficit stress for 7 days. Pruning weight, root and aerial dry weight and transpiration were recorded and the experiment was repeated during two years. Transpiration efficiency (ratio between aerial biomass and transpiration) was calculated and δ13C was measured in leaves for the baseline and stable water deficit periods. A large genetic variability was observed within the panel. The rootstock had a significant impact on nocturnal transpiration which was also strongly and positively correlated with maximum daytime transpiration. The correlations with growth and water use efficiency related traits will be discussed. Transpiration data were also related with VPD and soil water content demonstrating the influence of environmental conditions on transpiration. These results highlighted the role of the rootstock in modulating water deficit responses and give insights for rootstock breeding programs aimed at identifying drought tolerant rootstocks. It was also helpful to better define the mechanisms on which the drought tolerance in grapevine rootstocks is based on.

Pressing has a relevant impact on the characteristics of the must and subsequently on white wines produced [1]. Therefore, the adequate management of pressing can lead to the desired extraction of phenols and other grape compounds (i.e. Organic acids), aromas and their precursors, allowing the production of balanced wines [2]. This aspect is especially important to sparkling wine where the acidity and pH, and the content of phenols affect its longevity and the expected sensory character.