Phenology-driven infestation patterns of the carob moth (Ectomyelois ceratoniae) in Mediterranean walnut orchards: Insights from comparison with codling moth (Cydia pomonella).

BACKGROUND: While Cydia pomonella has long been regarded as the key lepidopteran pest of walnut in Europe, field observa- tions increasingly indicate that Ectomyelois ceratoniae is becoming dominant in Mediterranean orchards. To assess their rela- tive importance, we compared the incidence and seasonal dynamics of both species across multiple orchards and years. Because fruit susceptibility varies with ripening stage, aligning pest monitoring with host phenology may improve the timing and integration of control tactics. This study examined the synchrony between walnut phenology and the temporal patterns of adult occurrence and larval infestation of E. ceratoniae and C. pomonella to develop phenology-driven integrated pest manage- ment (IPM) strategies. RESULTS: Over two seasons and three orchards, E. ceratoniae consistently outnumbered C. pomonella in trap captures and larval recoveries. Infestation was concentrated at advanced ripening stages, peaking between the packing tissue brown (PTB) stage and husk dehiscence. Adult captures systematically preceded larval entry into the kernels, confirming the effectiveness of pher- omone traps as early-warning tools when interpreted alongside phenological observations. The stabilized lure (7Z,9E,11-dodecatrienyl formate with butylated hydroxytoluene) produced reliable flight curves. The interval between pistil- late flower receptivity and PTB was highly consistent (≈126–129 days), allowing reliable estimation of the high-risk period. CONCLUSION: Ectomyelois ceratoniae was responsible for most of the infestation pressure in ripening and mature fruits, sup- porting its role as the main late-season lepidopteran pest of Mediterranean walnuts. Early harvest after PTB stage, combined with orchard sanitation and pheromone-based monitoring, can substantially reduce infestation risk. These findings provide a practical, phenology-driven IPM framework to safeguard walnut quality and support the inclusion of E. ceratoniae in official production guidelines.