Exploiting somaclonal variability to increase drought stress tolerance in grapevine 

From Porto and then through Bordeaux, Champagne and Bourgogne, wine geographical indications (gi) were the driving models for this form of protection of distinctive signs for collective use. Many studies present the benefits of recognizing a gi for a given region, the challenges of its implementation, as well as the possibilities of promoting territorial development.

Anthocyanins and phenolic compounds play a crucial role in winemaking, contributing to the profile, flavor, color, texture, and stability of wine. Grape clusters, specifically Vitis vinifera L. cv. Grenache, were handpicked from a commercial vineyard sited in Tudelilla, La Rioja, Spain (42°18′ 52.26″, Long. -2°7′ 59.15″, Alt. 582 m) on five distinct dates from veraison to harvest during the 2015 season. Non-contact spectral measurements were conducted on intact grape berries using a VIS-NIR spectrometer operating in the 570 – 1000 nm spectral range under controlled laboratory conditions, positioned at a distance of 25 cm from the berries. The quantification of 16 anthocyanins and phenols in 120 grape clusters was performed using HPLC, established as the reference method for validating the spectral tool.

Context and purpose of the study. The breeding of PIWI varieties has a long tradition in the Czech Republic. In the last two years, 9 new PIWI varieties have been registered.

In 2022, wine production was estimated at around 260 million hl. This high production rate implies to generate a large amount of by-products, which include grape pomace, grape stalks and wine lees. It is estimated that processing 100 tons of grapes leads to ~ 22 tons of by-products from which ~ 6 tons are lees [1]. Wine lees are a sludge-looking material mostly made of dead and living yeast cells, yeast debris and other particles that precipitate at the bottom of wine tanks after alcoholic fermentation. Unlike grape pomace or grape stalks, few strategies have been proposed for the recovery and valorisation of wine less [2].

Wine is one of the most consumed and appreciated beverages in the world. Due to the growing attention paid to consumer health, there is a continuous search for sustainable alternatives to common additives (such as sulfur dioxide) used to preserve wine. An example is represented by chitosan, the main derivative of chitin, approved for the treatment of must and wine since 2009 by the “international organization of vine and wine” (OIV/OENO 338a/2009) and by the european commission (EC Reg. No. 606/2009).