Decision support systems to improve direct control methods of codling moth (BIOFRUITNET Practice Abstract)

A combined strategy of various direct (granuloviruses; nematodes) and indirect measures (population models, pheromone traps) can lead to a reduction in codling moth populations in the long term. Practical recommendation Codling moth population model: • Forecasting models such as the Fruitweb model can be used to predict treatment dates and reduce the need for spray treatments. • Codling moth forecasting models provide predictions of possible egg-laying and hatching dates and help fruit growers make more accurate codling moth treatment decisions. • The Fruitweb model shows the current course of a codling moth population (moth flight, egg laying, larval development) in the orchard; codling moth development depends on climate, location/site, temperature and day length. • The Fruitweb model is based on the codling moth model by Graf, Höhn, Höpli and Kuske (2018). • For targeted and optimized control, own infestation monitoring (attractant traps) and the recommendations from agricultural advisors should always be used additionally. Explanation of the codling moth Fruitweb model (Picture 1) • The forecast models are calculated with approximate population strengths; the respective local weather conditions are included in the calculation; the calculation is performed retrospectively with the measured weather data and prospectively with the weather forecasts. • The upper diagram shows the course of the borings (red dotted line), as well as the number of larvae in the respective larval stages (larval stages L1-L5: various shades of orange and yellow, see legend on the bottom). • The middle diagram shows the daily oviposition, i.e., the number of eggs per day (red line). • The lower diagram shows (in green) the number of fertile females per day, the flight of the females depends mainly on the weather conditions and the time of day (crepuscular).