Extended investigation of fall armyworm resistance in the southern United States to four common Bt proteins

Monday, November 14, 2022

11:18 AM – 11:30 AM PT

Location: Vancouver Convention Centre, Meeting Room 210

Presenting Author(s)

TS

Tiago H. Silva

M.Sc student
Louisiana State University
Baton Rouge, Louisiana

Co-Author(s)

Ying Niu

Louisiana State University Agricultural Center
Baton Rouge, Louisiana
GS

Gregory Sword

Texas A&M University
College Station, Texas
JQ

Jawwad A. Qureshi

Associate Professor
University of Florida
Immokalee, Florida
GH

Graham P. Head

Global Head of Resistance Management
Bayer Crop Science
Frontenac, Missouri
DK

Dawson Kerns

PhD Student
University of Tennessee
Knoxville, Tennessee
Juan Jurat-Fuentes

Professor, Department of Entomology and Plant Pathology
University of Tennessee
Knoxville, Tennessee
XN

Xinzhi Ni

USDA-ARS
Tifton, Georgia
Daniel Carrillo

University of Florida
Homestead, Florida
CS

Caroline Sakuno

Centro de Tecnologia Canavieira
Piracicaba, São Paulo, Brazil

The fall armyworm, Spodoptera frugiperda, is a polyphagous pest targeted by transgenic corn expressing Bacillus thuringiensis (Bt) proteins in the Americas. Approximately 10 years ago, an areawide investigation documented that S. frugiperda has evolved practical resistance to single-gene Cry1F corn in the mainland United States. During the last decade, corn traits containing single insecticidal genes have been gradually replaced by pyramided Bt corn. Since the previous report, there have been no additional areawide studies about the status of Bt resistance in S. frugiperda in the United States. In this study, field populations of S. frugiperda were collected from different locations, planting histories, hosts, and environments across the southern United States. Laboratory bioassays were conducted to determine the relative susceptibilities of the field-collected populations to four common Bt proteins expressed in transgenic corn: Cry1F, Cry1A.105, Cry2Ab2, and Vip3A. Data generated for the study should have value in understanding the current status and factors related to the resistance development in S. frugiperda.

Keywords: Bt susceptibility, fall armyworm, Cry1F, Cry1A.105, Cry2Ab2, Vip3A