Leaf-curling plum aphid

The leaf-curling plum aphid (Brachycaudus helichrysi) is a significant pest belonging to the order Hemiptera and the family Aphididae. It is widely recognized for its migratory behavior and its specific impact on the health and productivity of stone fruit orchards globally.

This aphid primarily targets species of the Prunus genus, including plum, damson, and peach trees. During the summer months, it exhibits a migratory lifestyle, moving from its primary woody hosts to various secondary herbaceous hosts, including members of the Asteraceae and Boraginaceae families, before returning to trees in autumn.

The life cycle involves an alternation between asexual generations on trees and sexual generations in late autumn. Overwintering occurs in the egg stage on the bark of twigs or near the buds. As soon as temperatures rise in the spring, the nymphs emerge and begin feeding on the developing buds and young foliage.

Damage is characterized by the severe curling and distortion of leaves, which become chlorotic and stunted. The aphids produce copious amounts of honeydew, which supports the growth of sooty mold, blocking light and hindering photosynthesis. Heavy infestations result in reduced shoot growth, fruit deformity, and a significant decrease in the tree's vigor.

Effective management requires a combination of monitoring and chemical intervention. It is crucial to act early in the season before the leaves curl, as the curled foliage provides a protective barrier against many treatments.

• Regular orchard monitoring for early colonization
• Application of systemic insecticides at the bud-burst stage
• Conservation of natural predators like lacewings and ladybirds
• Good orchard sanitation, including the removal of weeds and suckers