Sustainable management of grapevine trunk diseases

The agri-food industry is constantly searching for ingredients of high functional value, healthy and of natural origin. One species of particular interest is Vitis vinifera, due to its recognized antioxidant potential. Among the grape varieties, one group possesses these antioxidant compounds not only in the skin, but also in its pulp: Teinturier. The red grape has traditionally been used for color correction purposes in winemaking, however, its high antioxidant content transforms it into a raw material of high potential for new formulations of ingredients and foods for the health and wellness market.

Atypical aging (ATA) is a white wine fault characterized by the appearance of notes of wet rag, acacia blossoms and naphthalene, along with the vanishing of varietal aromas. 2-aminoacetophenone (AAP) – a degradation compound of indole-3-acetic acid (IAA) – is regarded as the main sensorial and chemical marker responsible for this defect. About the origin of ATA, a stress reaction occurring in the vineyard has been looked as the leading cause of this defect. Agronomic, climatic and pedological factors are the main triggers and among them, drought stress seems to play a crucial role.[1]

The Maule region hosts up to a third of the total area of vineyards in Chile, in an environment where ancient practices inherited from the colonial past coexist with modernity and dynamism that include technified irrigation and fine vines. In the dry land of Maule there is a viticulture that has subsisted with ancient vines and traditions transmitted over generations, and there is little clarity about the origin and classification of the Maule viticulture, giving rise to the use of different concepts as synonyms to describe the ancient, minority, patrimonial or Criollas vines. In order to characterize and protect the ancient material, we studied the genetic diversity of a territorial collection that covers 80% of the communes of the region, prioritizing plants established more than 40-60 years ago.

Enzymatic browning[1] is an oxidation process that occurs in many foods that increases the brown colour[2]. This problem is especially harmful in the wine industry[3]. especially when the grapes are infected by grey rot since this fung release the oxidative enzyme laccase[4]. In the particular case of red wines, the presence of laccase implies the deterioration of the red colour and can even cause the precipitation of the coloring matter (oxidasic haze)[5].

Brettanomyces is a world-renowned yeast that negatively impacts the chemical composition of wines through the production of metabolites that negatively impact the sensory properties of the final product. Its resilience in wine conditions and ability to produce off-flavors make it a challenge for winemakers. Currently, the primary control technique involves adding sulfur dioxide (SO2); however, some Brettanomyces strains are developing resistance to this preservative agent. [1] Therefore, new management strategies are necessary to control this spoilage yeast.