Eco-Friendly Strategies for Vineyard Pest Suppression: Understanding Factors Limiting Natural Enemy Performance

Global viticulture is confronted by an extensive and economically significant assemblage of arthropod pests, fungal pathogens, and microbial diseases that challenge the sustainability of wine and table-grape production across every major producing region. The historically dominant reliance on synthetic chemical pesticides for vineyard pest control has generated well-documented adverse consequences, including the emergence of pesticide resistance, contamination of produce and the environment, disruption of beneficial non-target arthropod communities, and accelerating regulatory pressure to reduce pesticide inputs across wine-producing nations. Eco-friendly strategies centred upon the conservation, enhancement, and augmentative deployment of natural enemies have emerged as scientifically credible and practically viable alternatives or complements to chemical-intensive crop protection within integrated pest management (IPM) frameworks. Natural enemies spanning predatory mites and insects, parasitoid Hymenoptera and Diptera, entomopathogenic fungi, bacteria, and nematodes represent a biologically diverse, self-perpetuating, and economically invaluable resource for regulating phytophagous pest populations in vineyard ecosystems. Nevertheless, the consistent and reliable delivery of biological pest suppression under field conditions remains elusive, constrained by a complex web of interacting biological, agronomic, landscape-level, and climatic factors. This is a narrative review based on literature searches in Web of Science, Scopus, Google Scholar, and PubMed. This review critically synthesises contemporary scientific understanding of the principal eco-friendly pest suppression strategies employed in viticulture and, in particular, examines in depth the biological, ecological, and management-driven factors that limit natural enemy performance. Key limiting factors identified and reviewed include pesticide disturbance and sublethal residue toxicity; habitat simplification and landscape fragmentation; intraguild predation and the paradoxical effects of predator diversity; climate change, warming-driven phenological disruption, and microclimate variability within vine canopies; bottom-up effects propagated through host plant nutritional quality and herbivore-induced plant volatiles; hyperparasitism and secondary trophic disruption; the emergence of invasive pest complexes and ecological naivety in resident natural enemy communities; and dispersal limitation across fragmented viticultural landscapes. The review concludes that durable biological pest suppression requires the coordinated integration of multiple eco-friendly approaches within an adaptive, systems-level IPM framework, supported by landscape-scale habitat management, compatible pesticide programmes, and regionally calibrated natural enemy conservation measures. Priority research gaps are identified, including the insufficiently understood interactions between climate change trajectories and natural enemy community dynamics in viticultural landscapes.