Green beetle

Systematic position. The green beetle (Diabrotica graminea) belongs to the order Coleoptera, family Chrysomelidae. This species is an important agricultural pest, recognized for its specialized feeding habits that affect various crops in tropical and subtropical regions across the globe.

Host plants. This pest has a wide range of host plants, acting as a polyphage. It primarily attacks maize and sorghum, causing significant damage to roots and foliage. Additionally, it has been observed feeding on various legumes and vegetable crops, making it a versatile threat to diverse agricultural landscapes.

Biology and life cycle. The life cycle consists of four stages: egg, larva, pupa, and adult. Females deposit eggs in the soil near the base of host plants. The larvae emerge and descend to the root zone, where they feed intensively. After larval development is complete, pupation occurs within the soil, followed by the emergence of the adult beetles.

Damage and economic impact. The larvae are considered the most destructive stage, as their feeding on the root system significantly weakens the plant, often leading to lodging and reduced water and nutrient uptake. Adults feed on leaves, silk, and pollen, which negatively impacts pollination and grain development, potentially leading to substantial yield losses.

Management strategies. Effective management requires an integrated approach.

• Crop rotation to break the life cycle.
• Use of soil-applied insecticides at planting time.
• Monitoring adult populations with pheromone or sticky traps.
• Seed treatment with systemic insecticides.
• Proper irrigation management to minimize favorable conditions for larvae.