Maize billbug

Taxonomic position. The maize billbug (Sphenophorus maidis) belongs to the order Coleoptera and the family Curculionidae. It is a significant agricultural pest known for attacking corn crops, primarily within regions where its environmental requirements for overwintering are met.

Host plants. This pest primarily feeds on maize. While it shows a strong preference for corn, its ability to thrive in agricultural ecosystems makes it a persistent threat to maize cultivation. Damage is particularly severe in fields with continuous monoculture practices.

Biology and life cycle. The life cycle consists of four stages: egg, larva, pupa, and adult. Adults overwinter in protected areas such as crop debris or soil. In the spring, females deposit eggs into the base of young corn stalks, where the emerging larvae begin feeding on the internal tissues, disrupting nutrient transport.

Type of damage and economic importance. Adults cause minor damage by feeding on foliage, but the primary harm is inflicted by the larvae. By burrowing into the stalks at the crown, the larvae compromise the structural integrity of the plant, often causing stunting, wilting, and increased susceptibility to lodging.

Control measures. Integrated management is essential for controlling this beetle. Crop rotation is the most effective cultural practice to disrupt the life cycle. Additionally, removing crop residues and minimizing weed hosts are critical steps. Chemical control typically involves applying soil-incorporated insecticides at planting.

• Crop rotation with non-host plants
• Removal and destruction of crop debris
• Application of systemic insecticides during planting
• Field monitoring of early-season adult populations