Fall armyworm migration across the Lesser Antilles and the potential for genetic exchanges between North and South American populations.
The fall armyworm, Spodoptera frugiperda (J. E. Smith)(Lepidoptera: Noctuidae), is an important agricultural pest of the Western Hemisphere noted for its broad host range, long distance flight capabilities, and a propensity to develop resistance to pesticides that includes a subset of those used in genetically modified corn varieties. These characteristics exacerbate the threat fall armyworm poses to agriculture, with the potential that a resistance trait arising in one geographical location could rapidly disseminate throughout the hemisphere. A region of particular concern is the Caribbean, where a line of islands that extends from Florida to Venezuela provides a potential migratory pathway between populations from North and South America that could allow for consistent and substantial genetic interactions. In this study, surveys of populations from Peru, Bolivia, Paraguay, and Trinidad & Tobago expand on previous work in South America that indicates a generally homogeneous population with respect to haplotype markers. This population differs from that found in most of the Lesser Antilles where a combination of genetic and meteorological observations is described that indicate fall armyworm migration from Puerto Rico to as far south as Barbados, but does not support significant incursion into Trinidad & Tobago and South America. Air transport projections demonstrate that the wind patterns in the Caribbean region are not conducive to consistent flight along the north-south orientation of the Lesser Antilles, supporting the conclusion that such migration is minor and sporadic, providing few opportunities for genetic exchanges. The implications of these findings on the dissemination of deleterious traits between the two Western Hemisphere continents are discussed.
Center for Medical, Agricultural and Veterinary Entomology, USDA-ARS, Gainesville, Florida, United States of America.
Rodney N
RN
Nagoshi
Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
Shelby
S
Fleischer
Center for Medical, Agricultural and Veterinary Entomology, USDA-ARS, Gainesville, Florida, United States of America.
Robert L
RL
Meagher
Center for Medical, Agricultural and Veterinary Entomology, USDA-ARS, Gainesville, Florida, United States of America.
Mirian
M
Hay-Roe
Department of Life Sciences, The University of the West Indies, Saint Augustine, Trinidad & Tobago.
Ayub
A
Khan
Instituto de Tecnología Agroindustrial de Noroeste Argentino (ITANOA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Estación Experimental Agroindustrial Obispo Colombres (EEAOC), Tucumán, Argentina.
M Gabriela
MG
Murúa
CIRAD, UPR Agroécologie et Intensification Durable des cultures Annuelles, F-34398 Montpellier, France.|IRD, UR 072, Laboratoire Evolution, Génomes et Spéciation, Orsay, France.
Pierre
P
Silvie
Museo de Entomologia Klaus Raven Buller, Universidad Agraria La Molina, Lima, Peru.
Clorinda
C
Vergara
Insect Control and Cotton Disease Research Unit, USDA-ARS, College Station, Texas, United States of America.
John
J
Westbrook