title: Lambda-Cyhalothrin Resistance in the Lady Beetle Eriopis connexa (Coleoptera: Coccinellidae) Confers Tolerance to Other Pyrethroids.
abstract: Pyrethroid insecticides are widely recommended to control insect defoliators but lack efficacy against most aphid species. Thus, conserving aphid predators such as the lady beetle Eriopis connexa (Germar) is important to pest management in crop ecosystems that require pyrethroid sprays. In a greenhouse, early fourth-instar larvae and 5-day-old adults from susceptible (S) and resistant (R) E. connexa populations were caged on lambda-cyhalothrin-treated cotton plants, after which survival and egg production (for those caged at adult stage) were assessed. In the laboratory, similar groups were subjected to dried residues and topical treatment with one of eight pyrethroids (alpha-cypermethrin, bifenthrin, deltamethrin, esfenvalerate, fenpropathrin, permethrin, zeta-cypermethrin, and lambda-cyhalothrin), the organophosphate methidathion, or water and wetting agent. After caging on treated cotton terminals, 66% of the R-population larvae survived to adulthood, compared with 2% of those from the S-population. At 12 d after caging at adult stage under the same conditions, 64% of the females from the R-population survived and laid eggs, compared with 100% mortality and no oviposition for the S-females. In trials involving dried insecticide residues, gain in survival based on the survival difference (percentage for R-population minus percentage for S-population) across all tested pyrethroids varied from 3 to 63% for larvae and from 3 to 70% for adults. In trials involving topical sprays of the tested pyrethroids, survival differences ranged from 36 to 96% for larvae and from 21 to 82% for adults. Fenpropathrin and bifenthrin were the least and most toxic, respectively.
authors.affiliation: Departamento de Agronomia - Entomologia, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, CEP 52171-900, Recife, Pernambuco, Brazil. jtorres@depa.ufrpe.br.
authors.forename: J B
authors.initials: JB
authors.lastname: Torres
authors.affiliation: Departamento de Agronomia - Entomologia, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, CEP 52171-900, Recife, Pernambuco, Brazil.
authors.forename: A R S
authors.initials: AR
authors.lastname: Rodrigues
authors.affiliation: Departamento de Agronomia - Entomologia, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, CEP 52171-900, Recife, Pernambuco, Brazil.
authors.forename: E M
authors.initials: EM
authors.lastname: Barros
authors.affiliation: Universidade Federal de Alagoas, Centro de Ciências Agrárias, Campus Delza Gitaí, BR101-Norte, Km 85, CEP 57100-000, Rio Largo, Alagoas, Brazil.
authors.forename: D S
authors.initials: DS
authors.lastname: Santos
mesh_terms: D000818:Animals; D001517:Coleoptera; D007305:Insecticide Resistance; D007306:Insecticides; D007814:Larva; D009570:Nitriles; D011722:Pyrethrins
chemical_list: D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; C037304:cyhalothrin
keywords: Coccinellidae; cotton pest pyrethroid; integrated pest management; resistance