PlantwisePlus Blog

Last week, CABI confirmed that since it arrived in Africa in 2016, the Fall Armyworm (FAW) has been reported in 28 African countries, presenting a now permanent agricultural challenge for the continent. FAW mainly affects maize and can cut yields by up to 60%. In research funded by the UK’s Department for International Development (DFID), CABI estimate that, if not properly managed, the pest will cost 10 of Africa’s major maize producing economies a total of $2.2bn to $5.5bn a year in lost maize harvests.
“Enabling our agricultural communities with quick and coordinated responses is now essential, to ensure the continent stays ahead of the plague,” said Dr Joseph DeVries from the Alliance for a Green Revolution in Africa (AGRA).
As countries turn to pesticides to reduce the damage, farmers face the risk of the pest developing resistance to treatment, which has become a widespread problem in the Americas. Biopesticides are a lower risk control option, but few of the biopesticides used in the Americas are yet approved for use in Africa, raising the need for urgent local trials, registration and the development of local production.

“Maize can recover from some damage to the leaves. So when farmers see damaged leaves, it doesn’t necessarily mean they need to control. Research is urgently needed, and a huge awareness and education effort is required so that farmers monitor their fields, and can make decisions on whether and how to control,” said Dr Roger Day, CABI’s Sanitary and Phytosanitary (SPS) Coordinator.
“There are natural ways farmers can reduce impact, including squashing the eggs or caterpillars when they see them, and maintaining crop diversity in the farm, which encourages natural predators.”
CABI has also warned of the need to address the human health issues raised by extensive use of chemical pesticides. “Resource poor farmers are often unwilling or unable to buy the appropriate safety equipment and in some cases they use pesticides without appropriate application equipment. Farmers may also be disinclined to use safety equipment when hot weather makes it extremely uncomfortable. Recognising that farmers will still want to use pesticides, specific measures are needed to make lower risk biopesticides more accessible,” said Dr Day.
Agricultural researchers are also now working to identify a natural biological control agent, such as a parasitic wasp that lays its eggs inside the FAW eggs. Dr Day hopes that in time, this may provide the most sustainable solution to Africa’s newest pest infestation.
To find out more about what CABI is doing in the fight against FAW please visit www.cabi.org/fallarmyworm