Sustainable Management of Postharvest Fungal Pathogens in Date Palm (Phoenix dactylifera L.) Production: An Efficacy Evaluation of Natural Antifungal Agents

Postharvest fungal diseases represent a significant threat to date palm (Phoenix dactylifera L.) fruit marketability and economic viability. This comprehensive study evaluated the antifungal efficacy of essential oils (cinnamon, clove), plant extracts (ginger, turmeric), and organic acids (ascorbic and salicylic acid) against three major fungal pathogens isolated from 125 infected date palm fruit samples collected from supermarket locations in New Valley Governorate, Egypt. Fungal pathogens were identified through combined morphological analysis and ITS rDNA sequencing with >99.47% identity to GenBank reference strains, yielding 43 fungal isolates with confirmed pathogenicity. In vitro assays demonstrated that cinnamon oil achieved 34.1% inhibition of Curvularia spicifera at 1% concentration (p < 0.05). Ginger extract achieved 83.3% inhibition of Aspergillus niger at 5% concentration (p < 0.05). In vivo studies on stored dates revealed substantial disease suppression with cinnamon oil at 10% concentration, achieving moderate disease suppression (26.7% incidence and 23.3% severity; p < 0.05) for C. spicifera after 3 months storage. Ascorbic acid consistently reduced mycelial growth by >59% across multiple pathogens (p < 0.05). These findings demonstrate the potential of cinnamon and clove essential oils combined with ascorbic acid as sustainable, organic-certification-compatible alternatives for managing postharvest date palm diseases.