Oblique-banded leafroller

The Oblique-banded leafroller (Choristoneura rosaceana) is a member of the order Lepidoptera and the family Tortricidae. It is a highly destructive and polyphagous insect pest that poses a significant challenge to commercial orchards, nurseries, and ornamental garden management worldwide.

This moth species infests a wide range of host plants, predominantly focusing on Rosaceae family members. Economic damage is most severe in apple, pear, cherry, plum, and peach orchards. Furthermore, it frequently attacks small fruits such as raspberries, blueberries, and various ornamental flowering shrubs.

The biological cycle typically features two generations per year in most temperate regions. Larvae overwinter in sheltered silk hibernacula within bark crevices or protected plant structures. In early spring, larvae emerge to feed on developing buds, subsequently progressing to foliage, blossoms, and developing fruits as the season advances.

Damage is characterized by larvae folding or rolling leaves together using silk webbing, creating a protective nest where they feed undisturbed. Beyond leaf destruction, larvae may burrow into the surface of fruit, causing deep feeding scars. These wounds not only ruin the aesthetics but also render the fruit susceptible to secondary pathogens and rot.

Effective management requires an integrated approach. Cultural practices, such as removing abandoned host trees and cleaning up leaf litter, help reduce overwintering populations. Chemical intervention should be timed precisely to target early-instar larvae before they create protective webbed shelters, often utilizing selective insecticides that spare beneficial predator populations.

• Implementation of pheromone traps for flight monitoring.
• Use of Bacillus thuringiensis (Bt) for biological control.
• Orchard sanitation including removal of infested fruit and prunings.
• Biological control through the release of parasitoid wasps.