Sugarcane beetle

Systematic position. The sugarcane beetle (Ligyrus subtropicus) is a member of the order Coleoptera and the family Scarabaeidae. This species is known for its specialized feeding habits and can cause significant economic losses in various tropical and subtropical agricultural environments.

Crops and damage patterns. The primary crop impacted by this pest is sugarcane. Adult beetles and their larvae infest the underground parts of the plant. Adults bore into the base of the stalks, disrupting nutrient uptake and often causing the plants to lodge or die, while larvae focus on feeding on the root system, stunting the plant's growth.

Biology and life cycle. The life cycle consists of the egg, larval, pupal, and adult stages. Females lay eggs in moist, organic-rich soil. Upon hatching, the larvae reside in the soil, feeding on organic matter and living roots for several months. Adults are nocturnal, showing a strong attraction to artificial light sources, which is often utilized for population monitoring.

Economic importance. The damage inflicted by Ligyrus subtropicus is most critical during the early growth stages of the crop. High populations can cause patchy stands and significantly reduce the final yield. In endemic areas, the cumulative impact of root feeding and stalk boring makes this beetle a primary management target for sugarcane producers.

Protection measures. Effective control requires an integrated pest management (IPM) strategy:

• Cultural practices such as deep tillage to disrupt the soil environment for larvae.
• Application of soil-incorporated insecticides at the time of planting to protect young plants.
• Implementation of crop rotation to reduce beetle population density in the soil.
• Use of light traps to monitor adult activity and time chemical control interventions appropriately.