Why Peacock Eye Severity Varies with Olive Tree Orientation: Defining Criteria to Predict Infection Events.

Area of Science:

• Plant Pathology
• Agricultural Science
• Mycology

Background:

• Peacock eye disease, caused by *Venturia oleaginea*, is a major threat to olive production in Israel.
• Current management relies on seasonal fungicide applications, but environmentally friendly, precise timing is needed.

Purpose of the Study:

• To define environmental criteria for predicting peacock eye disease infection events in olive trees.
• To develop a more precise, environmentally conscious disease management strategy.

Main Methods:

• Observed disease severity and leaf abscission in relation to canopy orientation and microclimate.
• Conducted *in-vitro* experiments to determine optimal conditions for fungal spore germination and sporulation.
• Correlated weather variables with disease incidence to identify key infection triggers.

Main Results:

• Leaf wetness duration due to dew showed significant differences between canopy sides, influencing disease severity.
• Identified specific environmental criteria for infection: ≥15 mm rain, ≥6 hours wetness duration, and 12-18°C during wetting.
• Uneven disease distribution across canopy orientations aided in pinpointing critical weather variables.

Conclusions:

• The defined criteria provide a reliable method for predicting peacock eye disease infection events.
• These criteria can optimize fungicide application timing, enhancing disease control and environmental sustainability in olive cultivation.