Revisiting fall armyworm population movement in the US and Canada

Wednesday, November 16, 2022

3:30 PM – 3:42 PM PT

Location: Vancouver Convention Centre, Meeting Room 110

Presenting Author(s)

Shelby J. Fleischer

Professor, Emeritus
Pennsylvania State University
University Park, Pennsylvania

Co-Author(s)

Ashley Tessnow

Postdoctoral Research Associate
Texas A&M University
College Station, Texas
Robert L. Meagher, Jr. (he/him/his)

Research Entomologist
USDA-ARS
Gainesville, Florida
RN

Rodney Nagoshi

USDA-ARS
Gainesville, Florida

Using an expanded dataset extending into Canada, we confirm the consistency of haplotype patterns that relate overwintered origins of fall armyworm populations to hypothesized dispersal trajectories in North America and compare the geographic distribution of these patterns with previous model projections. We confirm the general accuracy of previous modeling efforts, except for late in the season where models predict that areas of the Midwest will show significant overlap with populations from Florida and Texas while the observed haplotypes show a strong Texas ratio.We test the hypothesis that the Appalachian Mountains influence geographic patterns of haplotypes, potentially serving as a barrier to gene flow between the Texas and Florida natal populations. We also delineate the western and northern limits of the migration from Florida and show that while substantial mixing of the Texas and Florida migrants routinely occurs north of South Carolina it is apparently of no hereditary consequence since this population does not appear to return to the Florida overwintering sites.