A new policy brief on the dreaded pest lays out the case for using agroecological approaches.
Solutions to the massively destructive pest, fall armyworm (Spodoptera frugiperda), are urgently needed. In Sub-Saharan Africa, governments have spent huge sums purchasing and distributing pesticides — including many highly toxic chemicals that have been banned in other parts of the world — as an emergency measure. Unfortunately, often even these chemicals are not effective but rather pose a significant risk to human health and the environment.
Without proper training and the right advice about usage, smallholders often use the pesticides without following safety measures, such as wearing protective clothing while preparing or spraying the chemicals and the safe disposal of the used containers. This can result in short-term or chronic health problems, depending on duration of exposure, how much toxin is ingested and the pesticide toxicity.
Native to the Americas, the fall armyworm was first detected in Africa in 2016 and has since spread across the continent, leaving a trail of damaged crops. The pest is able to feed on over 350 plant species. It consumes a wide variety of cereal crops — such as maize, sorghum and wheat — but has a particular preference for maize, which is the staple grown by most farmers in Sub-Saharan Africa. This seriously challenges food security and incomes for many years to come.
Fortunately, over 150 parasitoid species and other natural predators — including spiders, beetles, ants, social wasps, insectivorous birds and bats — are known to attack fall armyworm. These natural enemies are abundant in most smallholders’ fields and data indicate that they provide effective control of the pest in many situations. Patches of natural and semi-natural habitats around farms help to attract diverse natural enemies that feed on fall armyworm at different stages of their life cycles. Therefore, the application of highly toxic pesticides risks damaging this natural pest-control service.
World Agroforestry (ICRAF) is researching low-cost, non-toxic, highly specific strategies for smallholders to manage fall armyworm. Lead researcher Rhett Harrison said preliminary results show that agroecological approaches are effective against the pest and also providing other benefits.
‘We have recorded significant results where agroecological approaches are being trialled in the control of fall armyworm,’ he said. ‘Many of the plots where the intercropping of legumes has been done have healthier plants and soil as well as an abundance of natural enemies.’
Principal entomologist Gilson Chipabika at the Zambian Agricultural Research Institute advocates for cautious use of chemicals.
‘Many of the chemical pesticides farmers are using are highly toxic, also killing the predators that naturally feed on fall armyworm,’ he said. ‘Through this study, we intend to develop low-cost options that farmers can use to manage this pest sustainably.’
Eneless Mweemba, a farmer in Kazungula District, said it was unbelievable that she was managing to control pests without chemicals.
‘I never once thought controlling pests was possible without chemical pesticides,’ she said. ‘Am glad we are learning the use of agroecological approaches that are safe and less expensive.’
The fall armyworm project is a five-year project seeking to develop low-cost options for smallholders to manage the devasting pest threatening the livelihoods of millions of people. The project is funded by the Norwegian Agency for Development Cooperation and implemented by ICRAF, Zambian Agricultural Research Institute and the Malawi Department of Agricultural Research Services.