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

ended

In recent years, a general decline has been documented in several agriculturally relevant woody plants, and numerous reports point towards a possible role of the plant-associated microbiome. This especially applies to grapevines (Vitis vinifera L.) and to the recent outbreak of grapevine trunk diseases (GTD). This cluster of fungal diseases is considered the greatest challenge 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 clonal propagation process, are believed to have led to an imbalance in grapevines endophytic microbiome, which may be a key explanation for the recent success of GTD-associated pathogens. The best candidates to investigate the composition of a balanced 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 endophytic microbiome diversity of wild populations of VVS, using DNA metabarcoding and in vitro isolation techniques; (2) re-introduce endophytes isolated from VVS in cultivated grapevines, by means of a synthetic microbiome transfer; (3) assess the efficacy of 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, but have also the potential to provide a concrete solution to viticulture, for the benefit numerous European and non-European countries.