Novel approaches and promising perspectives for enhancing grapevine editing and regeneration

Organic wine production and consumption is one of the sustainable practices contributing to a number of sustainable development goals (SDGs).

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).

AIM To determine the effect of both ripeness and enzyme maceration on the astringency and bitterness perception of Cabernet Sauvignon winesRecent work has contributed to a more detailed understanding of the grape cell wall deconstruction process from ripening through crushing and fermentation, providing a better understanding of what role polysaccharides play in post-harvest fermentation of grapes(1,2). Current research on glycomics in red wine making suggest polysaccharides are important sensory impact molecules (3–6). METHODSOur experimental system harvests Cabernet Sauvignon grapes at three different ripeness levels and makes wine both with and without enzyme treatment.

It is common to find tanks in the winery with wine below their capacity due to wine transfers between tanks of different capacities or the interruption of operations for periods of a few days. This situation implies the existence of an ullage space in the tank with prolonged contact with the wine causing its absorption/oxidation. Oxygen uptake from the air headspace over the wine due to differences in the partial pressure of O2 can be rapid, up to 1.5 mL of O2 per liter of wine in one hour and 100 cm2 of surface area1 and up to saturation after 4 hours.

In table grapes seedlessness is a crucial breeding target, mainly results from stenospermocarpy, linked to the Thompson Seedless variety. Several studies investigated the genetic control of seedlessness identifying AGL11, a MADS-box transcription factor, as a crucial gene.
We performed a deep investigation of the whole AGL11 gene sequence in a collection of grapevine varieties revealing three different promoter-CDS combinations. By investigating the expression of the three AGL11 alleles and evaluating their ability to activate the promoter region, we show that AGL11 regulates its transcription in a specific promoter-CDS manner. By a multi-AGL11 co-expression analysis we identified a methyl jasmonate esterase, an indole-3-acetate beta-glucosyltransferase, and an isoflavone reductase as top AGL11 candidate targets. In vivo experiments further confirmed AGL11 role in regulating these genes, demonstrating its significant influence in seed development and thus in seedlessness trait.