Fungus discovery offers hope against African armyworm, study finds

Letodi Luki Mathulwe, who works for the agriculture department in KwaZulu-Natal, made the discovery during an outbreak of African armyworm in 2025. Farmers were reporting fields full of dead caterpillars covered in a mysterious white substance. Mathulwe realised that something was killing the insects naturally and gathered samples for testing.

Her team's results, now published in a peer-reviewed research paper, confirmed that the fungus could be used against the armyworms. Mathulwe described it as a major breakthrough because existing chemical treatments are only effective in the early stages of the caterpillar's life, and nothing has proven effective against mature populations.

The African armyworm not only feeds on staple crops such as maize and sorghum but also releases a chemical compound in grass that can sicken cattle. Outbreaks can be devastating; one in 2017 was estimated to have destroyed up to 40% of Zambia's maize production. Last year's outbreak also caused problems for farmers in Zimbabwe and Malawi, where high inflation has compounded the difficulties.

Mathulwe said the discovery could lead to a product that farmers could use when the next outbreak happens, "eliminating the fear that the insect creates." She noted that more testing is needed before a product becomes available, but the finding creates hope for farmers whose animals and crops are at risk.