Expansion and Comprehensive Evaluation of the Peacock Eye Disease Management (PedMan) System across Olive Cultivars Differing in Susceptibility to Venturia oleaginea

Peacock eye disease, caused by Venturia oleaginea , is an important foliar disease of olive that is primarily managed through fungicide applications. Integrating host resistance into disease-warning systems could improve spray timing and reduce unnecessary fungicide use. PedMan (Peacock eye disease Manager) was previously developed and validated for highly susceptible olive cultivars. The objectives of the present study were to expand PedMan to cultivars differing in susceptibility to V. oleaginea and to evaluate the expanded system under commercial grove conditions. A sensitivity analysis of the rainfall and temperature criteria used for highly susceptible cultivars was conducted to establish criteria for moderately susceptible and moderately resistant cultivars. The rainfall threshold of ≥15 mm was retained, whereas the temperature range triggering an infection alert was narrowed from 12–18 °C for highly susceptible cultivars to 13–17 °C for moderately susceptible and 14–16 °C for moderately resistant cultivars. The expanded system was subsequently evaluated in 33 field trials and observations under natural infection conditions. PedMan recommendations were classified as correct or incorrect based on statistical comparisons of leaf abscission between fungicide-treated and untreated trees. Overall, 30 of 33 recommendations were correct, resulting in an accuracy of 90.9%. Sensitivity was 87.0%, while specificity and positive predictive value were both 100%. These results demonstrate that incorporating cultivar susceptibility into PedMan broadens its applicability and provides reliable cultivar-specific fungicide recommendations. The system has potential to reduce unnecessary fungicide applications while maintaining effective management of peacock eye disease across olive cultivars differing in susceptibility.