Pear leaf-curling aphid

Systematic position of the pear leaf-curling aphid places it within the order Hemiptera and the family Aphididae. This insect is a specialist pest that has co-evolved with its host plants, developing sophisticated mechanisms to exploit pear tree tissues.

Host plants that are primarily affected include various species of the genus Pyrus. The pest demonstrates a host-alternating life cycle, moving from its woody host, the pear tree, to herbaceous plants such as Tussilago farfara (coltsfoot) during the peak of the summer season.

Biology and life cycle involve overwintering as eggs on the bark of pear tree branches. Upon hatching in the spring, the stem mothers initiate colony formation on developing leaves. Throughout the summer, winged adults migrate to alternative hosts, only to return to the pear trees in late autumn to ensure the survival of the next generation.

Nature of damage and pest importance are characterized by the development of prominent leaf galls. These galls appear as reddish or yellowish blisters that cause the foliage to curl, wither, and eventually drop. The resulting stress significantly reduces the tree's vigor and negatively impacts fruit yield and quality.

Control measures require a multi-faceted approach. Cultural practices, such as removing the weed host Tussilago farfara from the orchard vicinity, are highly effective. Additionally, chemical control should be timed carefully, targeting the vulnerable early spring stages before leaf curling makes the aphids inaccessible to contact insecticides.

• Apply dormant oil sprays to target overwintering eggs.
• Manage weed populations within the orchard.
• Use systemic insecticides when early leaf curling is spotted.
• Promote the presence of natural predators like lacewings and ladybugs.