Stored-product Insect Pests in Saudi Dates: Host-pest Interactions, Parasitoid Incidence and Implications for Storage Biosecurity

Stored-product insects represent a major biosecurity challenge in agricultural supply chains, including commodities supporting food and feed systems. This study assessed infestation dynamics in Saudi date consignments during the 2023 season to characterize pest species, evaluate cultivar susceptibility and document the occurrence of natural enemies. Ten commercially important date cultivars were examined to identify the pest complex, quantify infestation intensity and link infestation patterns to cultivar traits and storage conditions.

Detailed assays quantified progeny output of Oryzaephilus surinamensis relative to biochemical traits (carbohydrates, fiber, ash, protein, moisture and pH) and assessed the effect of relative humidity (30-90%) on pest reproduction and fruit mass. Incidence of the larval parasitoid Bracon hebetor was recorded as a natural regulatory factor.

The almond moth Ephestia cautella was the dominant pest across regions, followed by O. surinamensis. Susceptibility varied between cultivars, with Sefri and Shibeibi most affected, whereas Barni and Ruziz were comparatively resistant. Biochemical analysis indicated that high carbohydrate and glucose-fructose dominant profiles favored O. surinamensis reproduction, while higher fiber, ash and moisture negatively correlated with progeny output. Increasing relative humidity enhanced fruit mass; pest reproduction peaked at 70% RH and declined at 90% RH. B. hebetor was detected at low frequencies, indicating limited natural suppression in storage environments. Pest prevalence, host biochemical traits and storage humidity jointly influenced infestation outcomes. These findings support integrated pest management strategies to improve storage biosecurity across agricultural supply chains linked to food and feed security.