title: Use of the synergist piperonyl butoxide can slow the development of alpha-cypermethrin resistance in the whitefly Bemisia tabaci.
abstract: The development of insecticide resistance in insect pests of crops is a growing threat to sustainable food production, and strategies that slow the development of resistance are therefore urgently required. The insecticide synergist piperonyl butoxide (PBO) inhibits certain insect detoxification systems and so may delay the evolution of metabolic resistance. In the current study we characterized resistance development in the silverleaf whitefly, Bemisia tabaci, after selection with either a neonicotinoid (thiacloprid) or pyrethroid (alpha-cypermethrin) insecticide alone or in combination with PBO. Resistance development was significantly suppressed (> 60%) in the line selected with alpha-cypermethrin + PBO compared to the line selected with alpha-cypermethrin alone. RNA sequencing (RNAseq) analyses revealed an increase in frequency of a knock-down resistance mutation but no differentially expressed genes were identified that could explain the sensitivity shift. No significant difference was observed in the level of resistance between the thiacloprid and thiacloprid + PBO selected lines, and RNA sequencing (RNAseq) analyses revealed that the cytochrome P450 monooxygenase CYP6CM1, known to metabolize neonicotinoids, was significantly upregulated (>10-fold) in both lines. The findings of this study demonstrate that PBO used in combination with certain insecticides can suppress the development of resistance in a laboratory setting; however, the mechanism by which PBO supresses resistance development remains unclear.
authors.affiliation: College of Life and Environmental Sciences, Biosciences, University of Exeter, Penryn Campus, Penryn, Cornwall, UK.|Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, UK.
authors.forename: C T
authors.identifier: 0000-0001-5771-7094
authors.initials: CT
authors.lastname: Zimmer
authors.affiliation: Department of Sustainable Crop Production, Section Sustainable Crop and Food Protection, Università Cattolica del Sacro Cuore, Piacenza, Italy.
authors.forename: M
authors.identifier: 0000-0001-5771-7094
authors.initials: M
authors.lastname: Panini
authors.affiliation: College of Life and Environmental Sciences, Biosciences, University of Exeter, Penryn Campus, Penryn, Cornwall, UK.|Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, UK.
authors.forename: K S
authors.initials: KS
authors.lastname: Singh
authors.affiliation: College of Life and Environmental Sciences, Biosciences, University of Exeter, Penryn Campus, Penryn, Cornwall, UK.
authors.forename: E L
authors.initials: EL
authors.lastname: Randall
authors.affiliation: Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, UK.
authors.forename: L M
authors.initials: LM
authors.lastname: Field
authors.affiliation: Hellenic Agricultural Organisation - "DΕMETER", NAGREF - Institute of Olive Tree, Subtropical Crops and Viticulture, Heraklion, Greece.
authors.forename: E
authors.initials: E
authors.lastname: Roditakis
authors.affiliation: Department of Sustainable Crop Production, Section Sustainable Crop and Food Protection, Università Cattolica del Sacro Cuore, Piacenza, Italy.
authors.forename: E
authors.identifier: 0000-0001-9845-6038
authors.initials: E
authors.lastname: Mazzoni
authors.affiliation: College of Life and Environmental Sciences, Biosciences, University of Exeter, Penryn Campus, Penryn, Cornwall, UK.|Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, UK.
authors.forename: C
authors.initials: C
authors.lastname: Bass
mesh_terms: D000818:Animals; D019143:Evolution, Molecular; D020869:Gene Expression Profiling; D060005:Genotyping Techniques; D006430:Hemiptera / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D007305:Insecticide Resistance / Q000187:drug effects; D007306:Insecticides; D010574:Pesticide Synergists / Q000494:pharmacology*; D010882:Piperonyl Butoxide / Q000494:pharmacology*; D011722:Pyrethrins; D012641:Selection, Genetic; D059467:Transcriptome
chemical_list: D007306:Insecticides; D010574:Pesticide Synergists; D011722:Pyrethrins; C017160:cypermethrin; D010882:Piperonyl Butoxide
keywords: Bemisia tabaci; PBO; insecticide resistance; knock-down resistance; synergism