Prospects for microbial control of the fall armyworm Spodoptera frugiperda: a review

The fall armyworm (FAW, Spodoptera frugiperda) is an important polyphagous insect pest in many crops. This highly invasive pest species originates from the Americas and recently spread rapidly across more than 100 countries worldwide. It poses a major threat to food security in a number of developing countries due to its rapid spread and distinctive ability to inflict widespread damage across multiple crops. Chemical insecticides are used as the main management strategy to control FAW in many parts of the world, particularly in the recently invaded areas in Africa and Asia. However, concerns over the adverse effects on environment and humans, and the development of resistance against insecticides have intensified efforts to develop alternatives that are effective and low-risk, while at the same time cost effective. Given that microbials are generally considered desirable options for pest management, this review compiles information on microbials in all phases of their development including entomopathogenic fungi, entomopathogenic nematodes, bacteria and baculoviruses, with a special focus on their efficacy against FAW. In addition, combinations of microbial agents and also mixtures with compatible insecticides for improved control of FAW are reviewed. The findings are discussed in light of improving management programs of FAW