Genetic Population Structure of Migratory Moths: the Fall Armyworm (Lepidoptera: Noctuidae)

Publisher Website
Google Scholar
Abstract
Populations of fall armyworm, Spodoptera frugiperda (J. E. Smith), were characterized genetically using electrophoretic methods to determine patterns of interbreeding, and to identify potential sources from which migrants enter the southeastern United States each year. Specimens were collected from nine locations in Mexico, the southeastern United States, and the Caribbean and were examined at 12 polymorphic loci over 1 year and, for some sites, 2 years. Significant heterogeneity among populations was found at five loci, particularly esterase-3 and hydroxybutyrate dehydrogenase, and population structuring was high relative to other Lepidoptera. Genetic differences were largely due to a highly divergent Puerto Rican population collected from rice (all other collections were from corn). If this differentiation results from a lack of interbreeding between Puerto Rico and the mainland and is not due to the presence of host races, then the source of immigrant fall armyworm for the eastern United States is not the Puerto Rican area but more likely overwintering populations from southern Florida, Texas, or Mexico.