Cold-induced anthocyanin accumulation in horticultural crops: mechanisms, trade-offs, and decision-driven temperature Management in Plant Factories

With the expansion of modern horticultural production systems, anthocyanins have attracted increasing attention for their dual role in imparting vibrant coloration and delivering health-promoting benefits. Preharvest temperature management, particularly controlled low-temperature exposure, has emerged as an effective strategy to enhance anthocyanin accumulation in horticultural crops. Despite extensive molecular insights, decision-driven temperature management (DDTM) frameworks that integrate species-, genotype-, and operational parameter-specific strategies for plant factory applications remain lacking. This review addresses this gap by proposing a DDTM-based framework that links molecular regulation to operational protocols for precise anthocyanin enrichment. Evidence is synthesized across diverse horticultural crops representing major production families, including Brassicaceae, Solanaceae, Rosaceae, and other representative horticultural groups, selected for their economic importance, high anthocyanin potential, and relevance to human health. Species- and genotype-dependent responses are highlighted, and key operational parameters, including temperature range, exposure duration, and preharvest timing, are analyzed to balance pigmentation intensity, biomass production, and energy efficiency. Plant factories are emphasized as enabling platforms for short-term end-of-cycle cooling and diurnal temperature modulation, which can be integrated with light spectrum management to optimize anthocyanin accumulation while maintaining yield stability. By organizing current knowledge into practical, decision-oriented temperature strategies, this review provides a framework to improve nutritional quality, compositional consistency, and functional value of anthocyanin-rich crops, supporting horticulture-driven quality assurance and resilient controlled-environment production systems.