A comprehensive guide on the integrated pest management of the Fall Armyworm (FAW) on maize was launched by the Food and Agriculture Organization of the United Nations (FAO) in February 2018.
The guide Integrated management of the Fall Armyworm on maize - A guide for Farmer Field Schools in Africa was developed with a host of partners: the International Institute of Tropical Agriculture (IITA), the International Centre of Insect Physiology and Ecology (ICIPE), Lancaster University, the Centre for Agriculture and Bioscience International (CABI), Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), Colegio de la Frontera Sur (ECOSUR) and the United States Department of Agriculture (USDA).
It aims to help smallholder farmers and frontline agricultural staff to manage FAW more effectively amidst fears that FAW may push more people into hunger. Central and Southern Africa are particularly on high alert, as the main maize-growing season is currently underway in these regions. By early 2018, only 10 (mostly in the north of the continent) out of the 54 African states and territories have not reported infestations by the invasive pest.
Based on a learning-by-doing approach and designed for Farmers Field Schools, the guide is packed with hands-on advice. It provides support for a correct identification of this new foe for African farmers, and offers options to manage it in an integrated, ecological and sustainable way.
The authors of the guide argue that information and recommendations regarding the role of pesticides in FAW management are urgently needed at a national policy level.
The guide warns that insecticide applications are costly, may not work because of resistance, poor application techniques, or low-quality pesticides, and will negatively affect FAW's natural enemies.
Although farmers may receive insecticides free this year, and maybe next, it is doubtful whether they will continue to receive them in the longer-term. Alternative and sustainable solutions must be found, as FAW is in Africa to stay and will be infesting maize fields for many years.
The actions taken to date in most countries have been limited to the use of synthetic pesticides (especially organophosphates, synthetic pyrethroids, a few neonicotinoids, and in some cases cocktails of pesticides). In some countries, the pesticide applications were mainly emergency responses, not based on a cost-benefit evaluation.
Bio-pesticides, including those based on bacteria, virus, and fungus, have been tested, developed, registered and used successfully in the Americas.
The use of botanical and biological insecticides (certain strains of Bacillus thuringiensis (Bt), fungi and virus) to manage FAW has been reported to be effective in several sources, but bio-pesticides are not always locally available in the affected countries.
Key guidelines and advice on effectively and sustainably managing FAW include:
• Visit the field and look at the status of the crop: its health and signs of presence of the FAW. Farmers can take direct action by crushing egg masses and young larvae.
• FAW damage can look alarming, but maize plants have a good capacity to compensate for that damage and often little yield is lost.
• Learn about FAW behaviour. For example: understanding how and where the adult female moth lays her eggs can help determine where to plant mixed crops to prevent further spread of FAW.
• Understand the important role of natural biological control in managing FAW. Studies have shown that FAW suffers up to 56 per cent mortality from parasitoids (beneficial insects such as tiny wasps killing eggs or larvae of the FAW) alone.
• Farmers must be able to recognize the FAW natural enemies and learn how to conserve and enhance them. Ants have already shown to be important FAW predators.
• Fields in Nigeria have already shown high levels of natural FAW mortality due to fungal and viral entomopathogens (pathogenic organisms killing FAW larvae). Farmers can ‘recycle' these naturally-occurring pathogens.
• Farmers can try "local remedies", including application of ash, lime, sand, or soil directly into infested whorls, already successfully used by some African farmers against FAW.