Soil microbiome analysis in an ESCA diseased vineyard

The soil microbiome is linked to the microbial ecosystem of aboveground plant tissues and it is able to modulate and stimulate plant responses. The community composition, i.e. diversity and abundance, is influenced by several factors such as agronomical practices, agrochemical practices and geographical location. For the first time, we present here the investigation of the microbial community related to the soil of a long-established cultivated vineyard using the meta-barcoding approach. Specifically, we analyzed the bacterial and fungal communities of the bulk soils associated with esca-symptomatic and asymptomatic vines. Results showed no significant differences in richness between the two types of samples. Conversely, we observed that esca-related pathogens and grapevine trunk disease (GTD) pathogens were more abundant in the bulk soils of symptomatic plants, suggesting that the soil could represent an important source of inoculum. We also identified two fungal genera, Curvularia and Coprinopsis, which are exclusive to the soil associated with asymptomatic plants. Moreover, Actinobacteria, a well-known group of bacteria symbionts, are over-represented in asymptomatic soils. Further studies are needed to expand the knowledge about these microorganisms, since they could have a role in controlling the development and/or spread of esca pathogens.