Plocaederus

Systematic position. The genus Plocaederus belongs to the order Coleoptera and the family Cerambycidae, commonly known as longhorn beetles or wood borers. These insects are specialized wood-feeders that have adapted to live and develop within the stems and branches of woody plants.

Host plants. These pests are primarily found in tropical and subtropical regions. They target various economically significant crops, including cacao, mango, cashew, and several citrus species. Their presence can severely impact orchards and plantations that rely on these tree species for commercial production.

Biology and lifecycle. The lifecycle starts when the female beetle lays eggs in the crevices or wounds of the tree bark. Upon hatching, the larvae immediately bore into the phloem and cambium layers. As they mature, they penetrate deeper into the wood, carving extensive galleries that compromise the structural integrity and vascular system of the host plant.

Nature of damage and pest status. The damage is primarily caused by larval feeding, which disrupts the transport of water and nutrients throughout the tree. Visible symptoms include canopy yellowing, thinning foliage, and the presence of sawdust-like frass at the base of the trunk. In severe cases, the tree may suffer from girdling, leading to rapid decline or death.

• Conduct regular field inspections for emergence holes and larval frass.
• Prune and destroy heavily infested branches or whole trees to reduce inoculum.
• Apply systemic or contact insecticides during the adult mating and egg-laying phases.
• Maintain optimal tree health through balanced fertilization and adequate irrigation.
• Deploy pheromone-based traps to monitor population spikes and time interventions correctly.