Pyrethroid resistance in Phytoseiulus macropilis (Acari: Phytoseiidae): cross-resistance, stability and effect of synergists

Autor(es)

Vitelli Queiroz, Maria Cristina ^[1] ; Sato, Mario Eidi ^[1]

Afiliação do(s) autor(es)

^[1] APTA, Inst Biol, BR-13001970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Experimental and Applied Acarology; v. 68, n. 1, p. 71-82, JAN 2016.
• Citações Web of Science: 2

Resumo

Phytoseiulus macropilis Banks (Acari: Phytoseiidae) is an effective predator of Tetranychus urticae Koch (Acari: Tetranychidae). The objectives of this research were to study the stability of fenpropathrin resistance and the cross-resistance relationships with different pyrethroids, and also to evaluate the effect of synergists {[}piperonyl butoxide (PBO), diethyl maleate (DEM) and S,S,S-tributyl phosphorotrithioate (DEF)] on fenpropathrin resistant and susceptible strains of this predaceous mite. The stability of fenpropathrin resistance was studied under laboratory conditions, using P. macropilis populations with initial frequencies of 75 and 50 % of resistant mites. The percentages of fenpropathrin resistant mites were evaluated monthly for a period of up to 12 months. A trend toward decreased resistance frequencies was observed only during the first 3-4 months. After this initial decrease, the fenpropathrin resistance was shown to be stable, maintaining constant resistance frequencies (around 30 %) until the end of the evaluation period. Toxicity tests carried out using fenpropathrin resistant and susceptible strains of P. macropilis indicated strong positive cross-resistance between fenpropathrin and the pyrethroids bifenthrin and deltamethrin. Bioassays with the synergists DEM, DEF and PBO were also performed. The maximum synergism ratio (SR = LC50 without synergist/LC50 with synergist) detected for the three evaluated synergists (PBO, DEM, DEF) was 5.86 (for DEF), indicating low influence of enzyme detoxification processes in fenpropathrin resistance. (AU)

• Processo FAPESP: 12/17972-2 - Resistência de pragas (Tetranychus urticae e Frankliniella occidentalis) e predadores (Acari: Phytoseiidae) a pesticidas e estratégias de manejo destas pragas
• Beneficiário: Mário Eidi Sato
• Modalidade de apoio: Auxílio à Pesquisa - Regular