Symptoms
Entry holes in trunk and branches with sawdust-like frass expelled. Sap exudation at bore holes. Girdling damage weakens branches causing sudden wilting. Trees become susceptible to wind breakage at tunneled points.
Prevention
Maintain tree vigor through good nutrition and irrigation. Protect bark from mechanical damage which provides entry points. Apply white wash to lower trunk. Remove and destroy dead wood promptly.
Treatment
Organic
Insert entomopathogenic nematodes or Beauveria bassiana into bore holes using a syringe. Seal holes with mud or grafting wax after application. Prune and destroy severely infested branches.
Chemical (last resort)
Inject chlorpyrifos or monocrotophos solution into bore holes using a syringe, then seal. Systemic insecticide soil drenches have limited efficacy for borers inside wood.
Affects 1 crop
Sources
MARDI Durian Production Guide; DOA Extension Bulletin