Plant Clinics and Farm Visits Diagnosing Fall Armyworm in Malawi

Margaret field visit
Mr. Guze Kampinga and CABI’s Dr Margaret Mulaa asses the damage caused by Fall armyworm

Mr. Guze Kampinga visits the plant clinic at Dowa Turn Off with his damaged maize samples and is received by Mrs Eluby Phiri a trained plant doctor.

“I have grown about 0.8 ha of rain-fed and 0.4ha irrigated maize (Ndimba). This year a strange pest has seriously damaged my maize and almost all people in this village are experiencing the same problem. The pest started damaging the crop a few weeks after germination and has continued damaging the crop up to now. I first noticed the tips of the maize funnel chewed and stunting yet I had applied fertilizer and there was sufficient moisture. When I checked the funnel I found small caterpillars inside, which were growing very fast. Later the leaves were chewed and holes seen in the cobs, they also feed on the kernels. I have tried to control the pest to no avail”, said Mr Guze.

He afterwards requested for a follow up visit by the plant doctors to assess the damage caused by the pest in his farm. Kapinga says he is stranded. He wonders how he is going to feed his family of 15 children and wife. He used to get 70-80 (50Kg bags) per hectare but now expects to harvest 40 bags per hectare since almost all plants are damaged. He is requesting for help from the government to provide more effective pesticides.

“I have sprayed chemicals as recommended by the extension staff but the pest is not dying, it has continued to damage the crop. So far I have sprayed 12 bottles, which has cost me 18,000 Kwacha. I am now very desperate and hopeless since I cannot afford more insecticides. I used to depend on irrigated maize but the pest has moved there as well and we expect even greater damage on the irrigated crop because the pest will move there after harvest”, he added.

FAW damage Malalwi
Fall armyworm feeding inside the maize funnel

Pesticides recommended by government to farmers in Malawi include Cypermethrin, Chlorpyrifos, Indoxacarb, and Deltamethrin. It is also recommended that farmers regularly scout and apply sandy soil into the maize funnels as soon as damage is observed or in all funnels when maize is at knee height. The sand is abrasive to the skin of the Fall armyworm (FAW) and will kill it.

Most of the farmers who attended the plant clinic at Dowa Turn Off in Kasungu Agriculture Development Division (ADD) said their maize had been attacked by FAW, which at first was mistaken for stem borers. This was correctly diagnosed later at the plant clinic and confirmed by CABI diagnostic laboratory as FAW. In order to effectively manage the pest, farmers were advised to plant early and regularly monitor their fields at the beginning of the growing season. Biopesticides such as Bacillus thuringiensis variety Aizawai could be used to manage the pest. Proper spraying using the appropriate pesticides is also recommended. Spraying should target the affected crop mainly focusing on the funnel where the young larvae are found. Timing insecticide application before the larvae burrows into the funnel is important because the big larvae are difficult to kill since they burrow into the funnel or cob. Spraying techniques and lack of equipment and proper protective clothing however remains a challenge.

FAW was first noticed in Kasungu district along Lisandwa River in Kasungu ADD in December 2016. By January it had spread to 9 districts and by March all the 28 districts in Malawi had been affected. FAW attacks leaves, stems, tassels, cobs and developing kernels.

Contributed by Margaret Mulaa, CABI