Kamel Charaabi1, Sonia Boukhris-Bouhachem2, Mohamed Makni3, Brian Fenton4, Ian Denholm5. 1. Medfly Rearing Facility, Research Unit UR04CNSTN01 'Medical Agricultural Application of Nuclear Techniques', National Centre for Nuclear Sciences and Technology (CNSTN), Sidi Thabet, Tunisia. 2. INRAT, Laboratoire de Protection des Végétaux, Ariana, Tunis, Tunisia. 3. UR Génomique des Insectes Ravageurs des Cultures d'Intérêt Agronomique (GIRC), Faculté des Sciences de Tunis, Université de Tunis El-Manar, El-Manar, Tunisia. 4. Scotland's Rural College, Bucksburn, Aberdeen, UK. 5. Department of Biological and Environmental Sciences, University of Hertfordshire, Hatfield, UK. i.denholm@herts.ac.uk.
Abstract
BACKGROUND: We used molecular assays to diagnose resistance to pyrethroids and pirimicarb in samples of Myzus persicae from field crops or an insect suction trap in Tunisia. Genotypes for resistance loci were related to ones for polymorphic microsatellite loci in order to investigate breeding systems and patterns of genetic diversity, and to inform resistance management tactics. RESULTS: The kdr mutation L1014F conferring pyrethroid resistance was found in all samples. The M918T s-kdr mutation also occurred in most samples, but only in conjunction with kdr. We discovered a previously unreported genotype heterozygous for L1014F but homozygous for M918T. Samples with modified acetylcholinesterase (MACE) conferring resistance to pirimicarb were less common but widespread. 16% of samples contained both the kdr and MACE mutations. Many unique microsatellite genotypes were found, suggesting that M. persicae is holocyclic in Tunisia. There were no consistent associations between resistance and microsatellite markers. CONCLUSION: This first study of insecticide resistance in M. persicae in North Africa showed genetic variation in insecticide resistance within microsatellite multilocus genotypes (MLGM s) and the same resistance mechanisms to be present in different MLGM s. This contrasts with variation in northern Europe where M. persicae is fully anholocyclic. Implications for selection and control strategies are discussed.
BACKGROUND: We used molecular assays to diagnose resistance to pyrethroids and pirimicarb in samples of Myzus persicae from field crops or an insect suction trap in Tunisia. Genotypes for resistance loci were related to ones for polymorphic microsatellite loci in order to investigate breeding systems and patterns of genetic diversity, and to inform resistance management tactics. RESULTS: The kdr mutation L1014F conferring pyrethroid resistance was found in all samples. The M918T s-kdr mutation also occurred in most samples, but only in conjunction with kdr. We discovered a previously unreported genotype heterozygous for L1014F but homozygous for M918T. Samples with modified acetylcholinesterase (MACE) conferring resistance to pirimicarb were less common but widespread. 16% of samples contained both the kdr and MACE mutations. Many unique microsatellite genotypes were found, suggesting that M. persicae is holocyclic in Tunisia. There were no consistent associations between resistance and microsatellite markers. CONCLUSION: This first study of insecticide resistance in M. persicae in North Africa showed genetic variation in insecticide resistance within microsatellite multilocus genotypes (MLGM s) and the same resistance mechanisms to be present in different MLGM s. This contrasts with variation in northern Europe where M. persicae is fully anholocyclic. Implications for selection and control strategies are discussed.
Authors: Ivair Valmorbida; Jessica D Hohenstein; Brad S Coates; Júlia G Bevilaqua; James Menger; Erin W Hodgson; Robert L Koch; Matthew E O'Neal Journal: Sci Rep Date: 2022-07-14 Impact factor: 4.996
Authors: Amen Hlaoui; Sonia Boukhris-Bouhachem; Daniela A Sepúlveda; Margarita C G Correa; Lucía M Briones; Rebha Souissi; Christian C Figueroa Journal: Insects Date: 2019-10-01 Impact factor: 2.769