Mulberry bark beetle

The Mulberry bark beetle (Liparthrum mori) is a tiny coleopteran species within the Curculionidae family, specifically the Scolytinae subfamily. It is a specialized pest that primarily infests trees of the genus Morus. It typically targets weakened, stressed, or poorly maintained trees, although high populations can also affect healthy specimens.

This beetle is considered an important pest in regions where mulberry trees are cultivated for fruit or sericulture. By tunneling into the inner bark, the insects disrupt the cambium layer, which is essential for transporting nutrients and water. Extensive tunneling can lead to the wilting and eventual death of branches and limbs.

The biological cycle begins when adult beetles bore into the bark to create galleries. Females deposit eggs within these tunnels, and upon hatching, the larvae continue feeding on the nutritious phloem and cambium. The development period can vary based on local climatic conditions, with multiple generations possible during a single long growing season.

The damage caused by Liparthrum mori is characterized by small entrance holes on the surface of the bark. Beneath the surface, the complex network of larval galleries causes the bark to loosen and eventually peel off. This damage makes the tree highly susceptible to dehydration, secondary infections, and drought stress, which further accelerates tree decline.

Effective management requires proactive monitoring and cultural practices to improve overall tree vigor:

• Regular inspection of bark for entry holes or wood frass.
• Pruning and destroying infested branches to reduce local pest populations.
• Maintaining optimal tree health through proper irrigation and soil nutrition.
• Application of chemical treatments, such as contact insecticides, timed with the adult emergence period.