How to control Adoxophyes orana in organic apple production: decision making, mating disruption and direct control measures (BIOFRUITNET Practice Abstract)

Summary

Since the methods often do not produce satisfactory results individually, the regulation of A. orana is carried out by a combination of insect pathogens, especially Bt - preparations, insecticides, confusion, as well as parasitoids as natural enemies.
Practical recommendations
• The most important representative of the fruit leaf roller is A. orana (in Central Europe 2 generations/year)
• Larvae of the overwintering generation cause feeding damage to the fruits, especially in September/ October, which concurrently might serve as an entry gate for secondary infections by different fruit pathogens (fungi).
• In organic cultivation, different pheromones for prevention and Granulovirus & Bt agents for direct control are available to control the pest:
• ISOMATE ® CLR MAX TT (pheromone): Combination dispenser to confuse the codling moth (C. pomonella) and fruit leaf roller (A. orana)
• Bacillus thuringensis: Bt is a toxin-producing bacterium; in organic orchards, it is used to regulate free-feeding butterfly caterpillars
• Granulovirus (e.g., Capex): infects the fatty tissue of the larvae so that they remain alive until the last larval stage and also still feed, therefore only limiting the damage by the subsequent generation; advantageous, however, is that due to the long life of the larvae, most parasitoids can fully develop in the larvae. The virus has a long-term effect because, after capex treatment, the granulovirus persists in the plants for a long time
• Parasitoids: Parasitoids depend on nectar and pollen for their egg maturation; at sites with a high incidence of A. orana, the emergence of parasitoids can be promoted by including flowering plants.