Climate-resilient Fruit Production: Integrating Genetics, Rootstocks, Canopy Management and Water-Smart Horticulture

Perennial fruit crops are exposed to climate change for decades after planting decisions are made, and their capacity for rapid adjustment is constrained by long juvenile periods, high establishment costs and clonal propagation. Declining winter chill, earlier flowering followed by spring frost, more frequent heat episodes, fruit sunburn, drought and the growing use of saline or reclaimed water now act simultaneously on many production regions. Adaptation research has expanded quickly, but it remains fragmented across breeding, rootstock physiology, canopy and microclimate engineering, and irrigation science. This critical narrative review examines how these four groups of levers can be combined to sustain yield stability, marketable fruit quality and water productivity in temperate deciduous fruit trees, grapevine, citrus and selected subtropical species. Peer-reviewed literature published from 2000 onwards was identified through multidisciplinary and life-science indexes, a regional scholarly platform, institutional sources and citation chaining, and was appraised qualitatively for design strength, scale, replication, measurement validity and transferability. The synthesis indicates that evidence is strongest for the physiological basis of chill and frost risk, for rootstock control of vigour, hydraulic supply and ion exclusion, for the sunburn-reducing effect of netting and evaporative cooling, and for water savings under regulated deficit irrigation during drought-tolerant phenological stages. Evidence is weaker, and frequently contradictory, for field-scale drought tolerance conferred by polyploid rootstocks, for the transferability of genomic prediction across environments, for agrivoltaic shading in orchards and for the long-term sustainability of irrigation with marginal water. Interactions among levers are rarely tested directly, although several trade-offs are consistently reported, including reduced red colour under protective nets, greater frost exposure of low-chill or early-flowering genotypes and increased sunburn risk when water deficit coincides with heat. Most field evidence is short in duration, concentrated in Mediterranean-type and temperate regions of the Northern Hemisphere and focused on a narrow set of cultivars. Multi-site, multi-season factorial trials, standardised plant-based stress indicators, phenology models calibrated for cultivars and rootstocks, and economic evaluation of combined adaptation packages are required before integrated recommendations can be made with confidence.