Fall armyworm (Spodoptera frugiperda)
The fall army worm is larvae stage of fall army worm moth. It is a migratory pest native to America and was first reported in Africa in 2016. The army worm causes damage by feeding on leaves and stems of maize, rice, sorghum, sugarcane, vegetable and cotton.
Fall army worm damages maize in all stages. In maize seedlings, it causes damage by feeding within the whorl. Larger larvae can cut the base of the plant. Mature plants suffer attack on reproductive structures. Symptoms of army worm damage in maize are a mass of holes on leaves and the whorl (funnel), ragged edges and larval frass. Young larvae skeletonize the leaf lamina. Severe feeding damage to young plants can kill the growing point; causing 'dead heart' in maize. Maize cobs are attacked by larvae boring through the kernels. At high densities, large larvae may act as armyworms and disperse in swarms, but they often remain in the locality on wild grasses, if available.
- Preventive measure: Intercropping maize with drought-resistant greenleaf desmodium and planting Brachiaria grass on the farm’s edge helps curb fall armyworms see under Push-pull
- Deep ploughing to expose larva to sun and to predators
- Weeding to enhance crop vigour
- Plant varieties with hard husk cover
- Biological control – use of parasitic Hymenoptera to act as larval parasitoids
- Scientists have already confirmed the effectiveness of using ash and chilli powder to control the fall armyworms in maize: Here is how farmers can do it: Buy ripe chilli powder (pepper) from the market or prepare your own using ripe pepper. Dry the pepper and make powder by either grinding or pounding, remove the big particles and leave the fine powder. Sieve cold wood ash from the fireplace.Get 1 gorogoro (2kg tin or plastic) of ash. Mix 1 gorogoro of wood ash with 5 teaspoonfuls of chilli powder. Mix the chilli and wood ash properly by shaking them in a container. Put the mixture in a used pesticide container that has small holes. Apply the mixture from the container by shaking it once into each plant funnel. For good results, apply the mixture immediately you see the worms in the maize and repeat the same if you notice any pests in the maize or pest damage to your crop.
- Spray plant extracts.
- Read more under publications Integrated management of the Fall Armyworm on maize (FAO 2018)