Decoding the mycobiome of grapevine organs in diverse Argentine regions

This study provides the first integrated analysis of fungal communities across soil, leaves, and must in Vitis vinífera cv. Malbec and Vitis vinífera cv. Cabernet Sauvignon from four key Argentine wine regions: Mendoza, San Juan, Salta, and Río Negro. Using high-throughput ITS metabarcoding, we characterised compartment-specific fungal diversity and network structures, revealing that the rhizosphere harbours the most diverse and environmentally driven communities, while leaf and must-associated microbiomes exhibit more structured and centralised networks. Core fungal taxa, including Cladosporiaceae, Pleosporaceae, and Lophiostomataceae, were consistently found across compartments, suggesting potential microbial exchange between belowground and aerial tissues. Region- and altitude-specific patterns highlighted the influence of edaphic and climatic factors, particularly the abundance of Metschnikowiaceae and Aureobasidium in high-altitude sites. Antagonistic interactions between Bacillus and pathogenic fungi such as Dactylonectria were also identified, reinforcing the role of microbial networks in plant health and vineyard resilience. This work underscores the ecological relevance of fungal communities in viticulture and supports the integration of microbial data into the terroir concept. These findings lay the groundwork for future studies aimed at improving vineyard management and wine quality through microbiome-informed strategies.