Physiological Constraints to Kiwifruit Productivity: The Central Role of Soil Structure, Water, and Nutrition

Kiwifruit ( Actinidia spp.) productivity is increasingly threatened by soil degradation, inefficient water management, and nutritional imbalance, despite the widespread adoption of intensive orchard systems. The progressive replacement of organic soil management with synthetic fertilizers, combined with climate‐driven increases in extreme rainfall events and inappropriate irrigation practices, has substantially altered soil structure, aeration, and biological functioning, impairing root activity, restricting nutrient uptake, and increasing vine susceptibility to waterlogging and hypoxic stress. This review critically synthesizes current evidence on the physiological constraints to kiwifruit productivity arising from the interactions among soil physical properties, water dynamics, and mineral nutrition, with particular emphasis on their role in the onset and progression of Kiwifruit Vine Decline Syndrome (KVDS). By integrating root–soil interactions, oxygen availability, nutrient mobility, irrigation strategies, and organic matter management, we identify key knowledge gaps and contradictions in the existing literature, and propose a conceptual framework linking soil structural integrity, water use efficiency, and nutrient balance to vine health, fruit quality, and orchard longevity. Evidence consistently points to the central role of soil compaction and waterlogging‐induced hypoxia as primary triggers of root degeneration and soil dysbiosis, while precision irrigation scheduling and balanced fertigation emerge as the most effective mitigation strategies. These findings underscore the urgent need to transition from input‐intensive approaches toward precision, soil‐centered management systems capable of sustaining kiwifruit productivity under increasingly challenging climatic conditions.