Fall armyworm caterpillars native to the Americas are spreading rapidly across mainland Africa, posing a major threat to the continent’s corn crops and food security in the region, according to new research published by the Centre for Agriculture and Biosciences International (CABI), an UK-based international not-for-profit organization that provides information and expertise on agricultural and environmental issues.
The invasive pest, which destroys young maize plants by attacking its growing points and burrowing into cobs, has not previously been reported outside of North and South America, the report said. Though the pest mainly imapcts corn crops, it is also known to eat more than 100 other species of crops, including grass crops like rice, sorghum, and sugarcane.
“We are now able to confirm that the fall armyworm is spreading very rapidly outside the Americas, and it can be expected to spread to the limits of suitable African habitat within just a few years,” said Dr. Matthew Cook, CABI chief scientist, in a statement. “It likely travelled to Africa as adults or egg masses on direct commercial flights and has since been spread within Africa by its own strong flight ability and carried as a contaminant on crop produce.”
Evidence of the pest has been found in several African countries. Researchers working at CABI’s Plantwise plant clinics identified two species of fall armyworms in Ghana last year, the results of which were confirmed by DNA analysis at the organization’s molecular laboratory in the UK. The organization noted a recent article by Reuters reporting that armyworms were suspected of destroying some 2000 hectares of crops in Malawi.
“The analysis of our collections from three different regions in Ghana has shown that both species or strains of the fall armyworm are widespread attacking maize. This is the first time it has been shown that both species or strains are established on mainland Africa,” said Dr. Cook. “Following earlier reports from Nigeria, Togo, and Benin, this shows that they are clearly spreading very rapidly.”
CABI said “urgent action” is required to combat the pest’s spread in Africa, reduce crop loss, and prevent its spread to Asian crops as well.
“This invasive species is now a serious pest spreading quickly in tropical Africa and with the potential to spread to Asia. Urgent action will be needed to prevent devastating loses to crops and farmers’ livelihoods. CABI will support national extension services to help farmers identify the different species quickly and accurately, and conduct studies to work out the best way to control it – for example, biological controls which reduce the need for insecticide,” said Dr. Cook.
Most farmers in the Americas have used chemical treatments to fight armyworm infestations with mixed results, CABI’s research posited. The organization plans to further an “Integrated Pest Management” strategy that is a combination of biological and cultural controls.