Brevipalpus phoenicis (Geijskes) is considered one of the most important pests on citrus in Brazil, due to the transmission of Citrus leprosis virus and the necessity of frequent acaricide applications for its control. This study was carried out to compare the toxicity of the main pesticides used on citrus in Brazil to the populations of B. phoenicis and the predaceous mites Neoseiuluscalifornicus (McGregor), Euseius concordis (Chant). Two populations of E. concordis were evaluated: one from Jaboticabal County and other from Descalvado County, State of São Paulo. Arenas of leaves (for phytoseiids) and fruits (for B. phoenicis) of Citrus sinensis (L.) Osbeck cv. Pera with 25 adult females of each species were sprayed under Potter spray tower. The mortality was assessed 72 hours after treatment. Four to six concentrations of each chemical (abamectin, acephate, azocyclotin, bifenthrin, chlorfenapyr, dicofol, dinocap, fenbutatin oxide, propargite and pyridaben) were used to obtain the concentration-mortality curves. Abamectin, azocyclotin, chlorfenapyr, dicofol, dinocap, fenbutatin oxide, propargite and pyridaben were highly toxic to B. phoenicis, presenting LC90 values equal or lower than the recommended concentrations of the chemicals. N. californicus was more tolerant to bifenthin, propargite, fenbutatin oxide and dinocap than B. phoenicis and E. concordis (both populations). These pesticides presented low toxicity to the adults of N. californicus, for which the LC50 of chemicals were at least six times higher than their recommended concentrations. Acephate was extremely toxic to E. concordis from Descalvado and Jaboticabal, but innocuous to adults of N. californicus. The population of E. concordis from Jaboticabal was more resistant to azocyclotin, bifenthrin, chlorfenapyr, dicofol and propargite than that from Descalvado.
predatory mite; leprosis mite; phytoseiid; acaricides; resistance
