Key Pillars to Sustainably Manage fall armyworm
Through its four regional hubs (West, Central, East, and Southern Africa) and several country stations IITA is the international research institute on the ground in Africa that has the most direct contacts with maize farmers. This decentralized approach, its multidisciplinary teams, and the largest organized Working Group dealing with plant health in the whole CGIAR, make IITA best suited to address the complex problem of the invasive FAW in a comprehensive manner, taking into account all aspects of IPM and working with our national, regional, and international partners.
With the establishment of the Biorisk Management Facility (BIMAF), a specialized research and training platform on the premises of the IITA-Benin Station, IITA and its partners are best equipped for designing and deploying appropriate responses to biotic threats such as those posed by FAW.
Over the past 30 years, IITA has developed and nourished a network of plant health partners all over Africa. At the international level, we collaborate with sister CGIAR Research Programs (CRPs), with research institutes such as CABI, CIRAD, the International Center of Insect Physiology and Ecology (icipe), and WASCAL, with SROs and local governments, NGOs and development organizations, and UN organizations such as FAO. These partnerships have been assembled mainly around multi-country and interdisciplinary projects to tackle specific plant health problems and have fostered solid mutual trust and synergies between national colleagues and IITA.
Also, IITA in partnership with CIMMYT is a co-leader of the Maize CRP and has developed varieties resistant to the prevailing stem borer species in Africa and synthesized newer genotypes with resistance to the invasive FAW. Furthermore, these institutions are presently accessing germplasm with proven resistance to FAW from USDA-ARS to expand the resistance base in African adapted germplasm.
Our comprehensive strategy to control FAW is based on four pillars
Early Warning and Rapid Response (EWRR): With the increasing incursions of invasive species including other climate-driven biorisks in Africa there is a crucial need not only for better preparedness of stakeholders but also for enhanced capacity among farmers to make a timely response. IITA and NIBIO will demonstrate joint expertise to launch a fitting EWRR decision support tool, using the Farming Interface App (FIA) co-developed by IITA and partners at MSU and integrated in the VIPS platform developed by NIBIO. FIA will be developed in several local languages, tested, and deployed for 1) guiding farmers scouting in their own fields, 2) empowering them to take real-time decisions with regard to pest management, 3) feeding back to the VIPS expert system real-time data on crop phenology, performance, pest occurrence, and severity for improving the accuracy of VIPS predictions at local and landscape levels.
Crop protection products: These are to be applied by maize farmers according to information provided by the above-described EWRR system. In the immediate short term and as an emergency response to FAW attacks in maize fields, farmers will have to use the best and least toxic insecticides available in the respective countries. However, as soon as more sustainable and less hazardous control products become available through the bio-pesticide development pipeline we will engage with CBOs and the private sector for their production and diffusion.
Biological control: This requires the introduction into Africa of better adapted natural enemies. In fact, as FAW is a recent invader from Latin America, it is expected (and already known from the literature) that natural enemies with greater efficiency exist in its area of origin than in Africa, including hymenopteran parasitoids and entomopathogenic microorganisms. After a series of suitability studies, the most promising biocontrol agents will be mass reared and released. This will be complemented by agroecological studies involving the wild host habitat for FAW in Africa and targeted chemical ecology studies to elucidate plant-pest-natural enemy interactions.
Host plant resistance: This pest has evolved with wild maize ancestors and later with modern maize in Latin America so it is expected that these constant interactions must have resulted in some forms of genetic adaptation. We hence propose to enhance current levels of resistance to FAW in adapted genotypes and develop and deploy newer and improved resistant lines and other populations for use in IPM strategies for the control of the pest.
Given the general cropping conditions in Africa, biological control will remain among the control options of primary choice and provide an opportunity for testing the most promising candidates. IITA is at the forefront to be a hub for reference collection of FAW parasitoids and mass rearing in West Africa at the Biodiversity Center. IITA is partnering with CABI and icipe to study FAW parasitoids and work at the taxonomic level using molecular tools to clarify the identity of the wasps from various geographical sources.
Georg Goergen: Taxonomist and Biocontrol Specialist, Head of the Biodiversity Center, G.Goergen@cgiar.org
Ghislain Tepa-Yotto: Entomologist, BIMAF coordinator, G.Tepa-Yotto@cgiar.org
Manu Tamò: Insect ecologist, IITA Representative in Benin, M.Tamo@cgiar.org