Blackberry psyllid

The blackberry psyllid (scientific name: Trioza tripunctata) is a small sap-sucking insect belonging to the order Hemiptera and the family Triozidae. It is a highly specialized pest that primarily targets members of the Rubus genus, causing significant physiological distress to host plants through its feeding activities.

The main host plant for this pest is the blackberry. Both nymphs and adults extract plant fluids, which negatively affects the vigor and health of the canes. Beyond direct damage, the psyllid is known to be a vector for phytoplasma diseases, which can result in long-term decline and potential mortality of the blackberry plantation.

The lifecycle of Trioza tripunctata typically involves an egg stage, five nymphal instars, and the adult stage. The insects overwinter as adults, usually residing in nearby coniferous trees. In early spring, they migrate to blackberry canes, where females deposit eggs on the rapidly growing terminals, ensuring an immediate food supply for the hatching nymphs.

The damage caused by these insects is distinct and often alarming to growers. Feeding triggers the development of curled, twisted, and stunted shoots, often described as "rosette" or "curly-top" symptoms. The leaves become brittle and chlorotic, significantly reducing the plant's capacity for photosynthesis and berry production.

Effective management and control strategies should prioritize the following actions:

• Managing the landscape by removing wild Rubus species and coniferous host trees near fields.
• Conducting regular field inspections during the early spring flush of growth.
• Applying systemic or contact insecticides during the peak migration and nymphal emergence windows.
• Pruning and destroying heavily infested canes to reduce the local population density.