Functions of NADPH-cP450 reductase in pesticide resistance, fecundity and host plant volatile location in Colorado potato beetle, Leptinotarsa decemlineata

Monday, November 14, 2022

9:24 AM – 9:36 AM PT

Location: Vancouver Convention Centre, Meeting Room 114/115

Presenting Author(s)

Casey Cruse

Graduate Student
Pennsylvania State University
University Park, Pennsylvania

Co-Author(s)

TM

Timothy W. Moural

Postdoctoral Fellow
Pennsylvania State University
State College, Pennsylvania
FZ

Fang Zhu

Professor
Pennsylvania State University
State College, Pennsylvania
Thomas C. Baker

Distinguished Professor Emeritus
Pennsylvania State University
State College, Pennsylvania
Andrei Alyokhin

Professor
University of Maine
Orono, Maine

The Colorado potato beetle (CPB) is a prominent insect pest of potatoes, tomatoes and eggplants all over the world, which results in the loss of billions of dollars annually. One management strategy to control this problematic pest is the use of numerous pesticides. However, CPB is well recognized for its ability in rapidly adapting to various biotic and abiotic stresses, including almost all major classes of pesticides used for control. Uncovering functions of key proteins in metabolic detoxification pathways will help us understand mechanisms of stress adaptation in this global agricultural pest. NADPH-Cytochrome P450 reductase (CPR) serves as a redox partner for microsomal cytochrome P450s and several other microsomal oxygenase enzymes in most eukaryotic cells. The full length Leptinotarsa decemlineata CPR (LdCPR) cDNA was isolated from an imidacloprid resistant population. The LdCPR gene was highly expressed during the early stage of embryonic development when compared to other life stages. Real-time PCR showed that the relative expression of LdCPR was higher in the antennae of imidacloprid resistant beetles compared to other tissues. Suppression of LdCPR expression increased susceptibility to imidacloprid in resistant beetles and reduced their attraction to the volatile odors of potato leaves. A significant decrease of fecundity in female beetles (29% less eggs/day) and the hatching rate (47%) of their eggs was also observed. Our results suggest that LdCPR plays vital roles in pesticide resistance, fecundity, and host plant volatile location.