Fifty fundamental questions to unlock the grapevine microbiome for sustainable viticulture : Lambers Opinion Paper

Current evidence supports associations between microbial biogeography, grape condition, fermentation communities and wine chemistry, yet much of this evidence is observational and strongly confounded by geography, climate, cultivar, and management, limiting the understanding and practical integration of the grapevine-associated microbiome into sustainable viticulture. We present a global, expert-driven synthesis of fifty priority questions identifying the main conceptual, methodological, and translational challenges in grapevine microbiome research. These questions were generated through a standardized survey of forty-four international experts and consolidated through structured review. The resulting framework spans nine thematic domains, from vineyard soil ecology, holobiont assembly, and plant–pest–microbe interactions to applied topics such as microbial product viability, circular-economy strategies, climate resilience, digital technologies, and socio-economic implementation. Collectively, the questions emphasize the need to: (i) define robust indicators of soil and holobiont health; (ii) unravel multi-domain microbial mechanisms underlying nutrient cycling, disease suppression, stress resilience, and grape yield and quality; (iii) assess how management practices and global change affect microbiome stability; and (iv) develop scalable microbiome-based solutions for vineyard regeneration and sustainable wine production. By articulating a coordinated research agenda across biological scales and viticultural systems, this work provides a roadmap to accelerate discovery, foster innovation, and support policy alignment with soil-health and climate strategies, ultimately enabling a more resilient and regenerative viticulture.