Stability and fitness costs associated with etoxazole resistance in Tetranychus urticae (Acari: Tetranychidae)

Autor(es)

Minazzi Stocco, Rafael Sorrentino ^[1] ; Sato, Mario Eidi ^[1] ; Santos, Taiana Lumi ^[1]

Afiliação do(s) autor(es)

^[1] APTA, Inst Biol, Caixa Postal 70, BR-13001970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Experimental and Applied Acarology; v. 69, n. 4, p. 413-425, AUG 2016.
• Citações Web of Science: 2

Resumo

The two-spotted spider mite, Tetranychus urticae Koch, is one of the most important pests on a wide range of crops worldwide. Studies on stability of resistance and possible fitness costs associated with etoxazole resistance were carried out in T. urticae to provide basic information necessary to define effective acaricide resistance management strategies for this pest. Selection for resistance to etoxazole was performed in a population of T. urticae collected from a commercial rose field, in Holambra County, in the State of So Paulo, Brazil. After five rounds of selection for resistance, the resistance ratio (R/S) at the LC50 reached 8739 fold value in comparison with a susceptible strain (Brazabrantes S Strain). The stability of etoxazole resistance was studied under laboratory conditions, using a population with initial frequency of 75 % of resistant mites. The frequencies of etoxazole resistance were evaluated monthly for a period of 13 months. The frequency of etoxazole resistance decreased from 75 to 37 % in this period. Comparison of biological traits between resistant and susceptible strains indicated the presence of fitness costs associated with etoxazole resistance. The resistant strain showed lower fecundity and a higher proportion of males in the population. The figures for net reproductive rate (R (0)), intrinsic rate of natural increase (r (m)) and finite rate of increase (lambda) were higher in the susceptible strain. The instability of etoxazole resistance is a favorable aspect for the acaricide resistance management in the spider mite. (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
• Processo FAPESP: 12/21538-6 - Resistência de ácaro-rajado, Tetranychus urticae Koch (Acari: Tetranychidae) a acaricidas e estratégias de manejo da praga em morangueiro e roseira
• Beneficiário: Rafael Sorrentino Minazzi Stocco
• Modalidade de apoio: Bolsas no Brasil - Programa Capacitação - Treinamento Técnico