African maize stalk borer

Systematic position: Busseola sorghicida belongs to the order Lepidoptera, family Noctuidae. It is a highly specialized agricultural pest, native to sub-Saharan Africa, recognized as a primary threat to cereal production due to its cryptic habit of living inside plant stems.

Host plants: The pest primarily infests members of the Poaceae family. Sorghum and maize are the most significant economic hosts. Additionally, various wild grasses serve as alternative hosts, enabling the insect population to persist even when primary crops are not in the field.

Biology and life cycle: The insect undergoes complete metamorphosis: egg, larva, pupa, and adult. Females deposit eggs under the leaf sheaths of young plants. Once hatched, the larvae bore into the stems, effectively shielding themselves from environmental stressors and biological control agents for the majority of their larval stage.

Damage and economic impact: The larvae cause severe physical and physiological damage to the host plants. Key indicators of infestation include:

• The "dead heart" symptom, resulting from larvae feeding on the apical meristem.
• Stem weakening, which makes the crops highly susceptible to lodging during windy weather.
• Significant grain yield reduction and stunted plant growth due to vascular system disruption.

Control measures: Management of Busseola sorghicida relies on integrated pest management (IPM) strategies. Essential practices include crop rotation and the prompt destruction of crop residues to eliminate overwintering sites. In severe infestations, the application of systemic insecticides during early crop stages is necessary to suppress larval populations before they enter the stem.