LC-HRMS data analysis of natural polymer homologue series Application on wine neutral oligosaccharides

Developing rootstocks adapted to environmental constraints constitutes a key lever for grapevine adaptation to climate change. In this context, Near Infrared Spectroscopy (NIRS) could be used as a high-throughput phenotyping technique to simplify the study of rootstocks in grafted situations. This study is an exploratory analysis to evaluate the potential of NIRS acquired on grafted tissues to reveal rootstock effects as well as the plasticity of combinations of scion/rootstock to better characterize these interactions.
Through the study of 25 combinations (5 scions times 5 rootstocks) in a dedicated experimental vineyard, we showed that NIRS obtained from grafted tissues capture rootstock and scion/rootstock interaction signals, up to 20% of the total variance at specific wavelengths.

Occurrence of freezing temperatures in early spring when grapevine shoots are developing is termed late frost in viticulture. Young green tissues are very sensible to temperatures below zero and damages often lead to important yield and quality losses such as the case in Europe in 2017. An indirect method to avoid late frost damage in vineyards consist in delaying the budburst. Previous research reported similar effects by applying vegetal oil on dormant buds. Here, we tested the application of rapeseed vegetal oil during late winter to delay the budburst on two V.vinifera cultivars of interest in Austria, Grüner Veltliner (GV) and Zweigelt (ZW).

Although some wine production processes still rely on post-production evaluation and off-site laboratory analysis, the new winemaking industry is aware of a need for a better knowledge of the process to improve the properties of the final product. Thus, more and more wineries are interested in incorporating quality-by-design (QbD) strategies instead of postproduction testing because of the possibility to early detect deviations in fermentation or any other wine process. This would allow to detect unwanted situations and eventually to ‘readjust’ the process, thus minimizing rejects.

In northern cold climate conditions, chilling requirement fulfillment in dormant grapevine buds is slowed or stopped by subzero temperatures impacting the transcriptional processes needed to complete chilling requirement. Cabernet Franc and Reisling in Geneva, NY were used to determine the impact of natural oscillating temperatures on grapevine bud transcriptional activity during light and dark periods of a two-week period in January with fluctuating diurnal winter temperatures. Cabernet Franc and Reisling bud samples were collected at 32 time points during the natural vineyard temperature cycle at 6:00 (dark), 14:00 (light) and 18:00 (dark) hours) to monitor gene expression in consecutive freezing and non-freezing temperature oscillations. Genotype, light and dark, and temperature oscillations conditions were explored.

Koshu is one of the indigenous grape variety that has been grown in Japan for more than one thousand years. Recent research showed that it has 70% of Vitis vinifera genes. In 2010, the Koshu variety was included in ‘International List of Vine and Varieties and their Synonyms’ managed by the ‘International Organisation of Vine and Wine’ and has further fueled its popularity in Japan. It is the most cultivated variety for winemaking in Japan.
Koshu berries have light purple skins. The variety is mainly used to produce white wines such as an aromatic wine and a wine produced by sur lie method although various styles are produced.