DNA-free editing to improve stress resilience of wine grape genotypes recalcitrant-to-regeneration

Xinomavro is the most important indigenous red wine variety grown in Northern Greece. It participates in the production of several PGI wines in Macedonia while from 100% Xinomavro the PDO “Amyndeon” and “Naoussa” are produced. The viticultural area of Amyndeon lies in a plateau of 550 ‐700 m of altitude, in a semi‐continental climate with mostly deep sandy loamy soils derived from limestone and marl bedrocks while in Naoussa, Xinomavro is grown in a Mediterranean climate on more heavy textured soils, sandy clay loam to clay, derived from ophiolithic, limestone and marl bedrocks, in an altitude which varies from 150 to 400 m. Different soil, climate and viticultural technique interactions, result in great variability with respect to morphological, ampelographical and physiological characters of Xinomavro as well as in the characteristics of the wines produced. 

Wine aroma represents one of the most important quality parameter and it is influenced by various factors (viticulture and vinification techniques, climate or storage conditions etc.). Wines produced from conventionally and ecologically grown grapes of same variety have different chemical composition and aroma profile [1]. Aroma profile of wine can be also influenced by additional treatment of wine, such as concentration of wine by reverse osmosis (RO). Reverse osmosis represents a pressure-driven membrane separation technique that separates the initial wine on the retentate or concentrate that is retained on the membrane, and permeate that passes through it [2]. Wine permeate usually containes water, ethanol, acetic acid and several low molecular weight compounds that can pass through the membrane. This property enables the use of reverse osmosis membranes for wine concentration, partial dealcoholization, acetic acid or aroma correction [3,4].

Less and less chemical plant protection products are approved by the E U. Plant pathogenic fungi become increasingly resistant to the active ingredients that have been around for a long time. Besides, there is a valid demand for effective products that can be applied in organic cultivation.
We examined Metschnikowia strains under laboratory conditions in order to find effective strains against B. cinerea. The antimicrobial mechanism of these yeasts is based on the competition for the ferric ions from the environment. Metschnikowia cells release the pulcherriminic acid which chelates with Fe3+, forming the pigment pulcherrimin.

The application of different winemaking techniques helps to modify the basic parameters, phenolic profile, and aroma components influencing the final wine quality. In particular, pre-fermentative processes aim to increase the extraction and preservation of grape native compounds. Among them, cold liquid stabulation (macération sur bourbes) consists in maintaining the grape juice on its lees, in suspended condition at low temperature (0-8 °C) for a variable time (generally from 7 to 21 days). The aim of this work is to apply the cold liquid stabulation on two Italian white grape varieties, Arneis and Cortese, to evaluate the impact on basic parameters, color, polyphenolic compounds (TPI), antioxidant power (DPPH), total polysaccharides, and free and glycosylated volatile compounds (GC-MS analysis) during and after the process.

Anthocyanins and tannins contribute to important sensorial traits of red wines, such as color and mouthfeel attributes.