Pear-mugwort aphid

The pear-mugwort aphid (Anuraphis pyrilaseri) is a significant pest belonging to the Aphididae family. It is a heteroecious aphid, meaning it alternates between two different host plants to complete its life cycle, which makes it a persistent challenge for pear growers across its range.

The primary host for this species is the pear tree (Pyrus), while its secondary host, which serves as a reservoir during the summer months, is various species of mugwort (Artemisia). This host alternation allows the pest to evade environmental stresses and continue its population growth throughout the entire growing season.

Development begins in early spring when nymphs hatch from overwintered eggs laid in the crevices of pear bark. They quickly colonize young leaves and growing shoots. Throughout spring, several generations are produced on the pear tree before winged forms migrate to their secondary host plants, returning to the pear trees in autumn for egg-laying.

The primary damage caused by this aphid involves severe curling and deformation of leaves, which curl into dense structures that provide shelter for the colonies. Furthermore, the secretion of honeydew promotes the growth of sooty mold, which impairs photosynthesis, stunts shoot growth, and reduces the overall vigor and yield of the trees.

Effective management strategies require a combination of chemical and cultural practices. Dormant season sprays can help reduce the population of overwintering eggs. During the active season, systemic insecticides are often necessary if colonization thresholds are exceeded. Cultural control is equally vital, focusing on the eradication of nearby mugwort patches to disrupt the aphid's migration cycle.

• Elimination of alternative host plants (Artemisia) near orchards.
• Early spring monitoring for initial aphid colonies.
• Application of selective systemic insecticides.
• Promotion of natural predators such as ladybirds and lacewings.