Plum rust mite

The plum rust mite (Aculus fockeui) is a microscopic pest classified within the family Eriophyidae, order Trombidiformes. Being extremely small, these mites are difficult to detect until significant damage to the host plant has already occurred, requiring professional monitoring techniques in professional orchards.

This pest primarily infests stone fruits, including plums, cherries, peaches, and apricots. It causes particular concern in nurseries and young plantations, where unchecked infestations can severely stunt tree development and reduce the vitality of new saplings throughout the growing season.

The life cycle of Aculus fockeui is closely synchronized with the phenology of its host plants. Overwintering females emerge from their hibernacula under bud scales as soon as spring temperatures rise. As the season progresses, they establish colonies on the underside of leaves, completing multiple generations that contribute to a rapid buildup of the population.

The damage caused by the plum rust mite is characterized by leaf curling, discoloration, and the formation of small galls or russeting on the leaf surface. As the mites feed on cellular content, the leaves often lose their green color, harden, and drop prematurely, which directly impairs the tree's ability to accumulate reserves for the following season.

• Dormant season applications of horticultural oils to target overwintering stages.
• Targeted acaricide treatments during the early leaf-development phase.
• Sulfur-based fungicides or acaricides applied to suppress active mite populations.
• Sanitation practices including pruning and removal of heavily infested shoot growth.
• Promotion of predatory mites which serve as natural biological regulators.