Halting the march of the armyworm: fungus discovery offers hope to African farmers

South African entomologist Letodi Luki Mathulwe has identified a naturally occurring soil fungus that kills African armyworms, a devastating pest threatening crops across east and southern Africa. The discovery, detailed in a peer-reviewed paper, offers potential control of mature armyworm populations where chemical treatments have proven ineffective. A 2025 outbreak that destroyed up to 40% of Zambia's maize in a prior year and disrupted food security across the region prompted the research breakthrough.

Mathulwe made the discovery while investigating fields of dead caterpillars in KwaZulu-Natal province, where they were enveloped in white fungal growth. The African armyworm damages staple crops including maize and sorghum while releasing compounds that sicken livestock. The fungus-based approach could address a critical gap: existing pesticides work only on early-stage caterpillars, not mature populations that spread as migrating moths.