Wild grapevines endophytic microbiome: ecology, epigenetics and application in the biological control of wood pathogens, a synthetic microbiome approach.

In recent years, a general decline has been documented in several agriculturally relevant woody plants, and numerousreports point towards a possible role of the plant-associated microbiome. This especially applies to grapevines (Vitis viniferaL.) and to the recent outbreak of grapevine trunk diseases (GTD). This cluster of fungal diseases is considered the greatestchallenge in modern viticulture, due to the complexity of the different pathosystems and the lack of reliable control strategies.During the last >100 years, vineyards have been routinely treated with fungicides, insecticides, herbicides and fertilizers.Recent research have demonstrated that such treatments and other anthropic intervention (e.g., domestication, grafting,training) affect the plant-associated microbiome. These human-driven alterations, exacerbated by grapevines clonalpropagation process, are believed to have led to an imbalance in grapevines endophytic microbiome, which may be a keyexplanation for the recent success of GTD-associated pathogens. The best candidates to investigate the composition of abalanced wood microbiome, unaffected by anthropic activities, are wild populations of V. vinifera subsp. sylvestris (VVS).In this multidisciplinary project, I will join the fields of plant pathology, epigenetics and microbial ecology to (1) unravel the endophyticmicrobiome diversity of wild populations of VVS, using DNA metabarcoding and in vitro isolation techniques; (2) re-introduceendophytes isolated from VVS in cultivated grapevines, by means of a synthetic microbiome transfer; (3) assess the efficacyof the synthetic microbiome in antagonizing GTD-associated pathogens, a next-generation approach to biological control.The outcomes of this project will not only contribute to advance our understanding of grapevine endophytes ecology, buthave also the potential to provide a concrete solution to viticulture, for the benefit numerous European and non-Europeancountries.