A novel strategy to control fall armyworm (Spodoptera frugiperda) with entomopathogenic nematodes

Native to the Americas, fall armyworm (FAW; Spodoptera frugiperda, JE Smith) recently invaded Africa where it was first detected in 2016. Today, FAW is present in most sub-Saharan countries, where it is causing great damage on a large variety of crops, but most importantly to maize. Effective, safe and sustainable control measures are desperately needed to ensure food security on the African continent. We have launched a project to explore the possibility of using entomopathogenic nematodes (EPN) to control FAW. The first step was to travel to Rwanda to find locally well-adapted EPN that can resist African climate. The second step is to determine the infectiousness of the Rwandan EPN strains on FAW larvae and to assess their multiplication capabilities with respect to commercial mass production and use. Commercial EPN strains that are internationally available will be also considered. The third step is to develop novel application methods of the EPN. Options are to apply the EPN in a paste or as a liquid spot spray onto the crop. Another option would be to encapsulate the EPN in alginate beads that could be manually placed onto the plants. We plan to incorporate attractants and feeding stimulants in the substrate to attract FAW and have them feed on the EPN-containing medium, which will increase the efficacy as well as the specificity of the control measure. The last step of this project is to test the application methods on African fields and assess their full potential to control FAW.