Current Status of Fall Armyworm Host Strains

Research on two host strains of the fall armyworm (FAW), Spodoptera frugiperda [J. E. Smith], is reviewed. They differ at allozyme loci and mtDNA restriction enzyme profiles, in their development on a variety of plants, and in their resistance to insecticides. Data on interstrain matings indicate unidirectional incompatibilities in the laboratory and strong preferences among males for females of their own strain in nature. Further study is required to clarify precise strain affinities for the long list of FAW host records. Information on phenologies and geographic distributions is presented but clearly in need of in-depth study. Those studying FAW are recommended to collect from a single host, to keep host records with laboratory colonies, to replenish colonies with individuals from the same host, and to establish a set of voucher specimens for each collection or study.