Journal of Insect Science (2008) 8 (3), 1-9

H. Jinfeng, L. Pei, S. Xueyan and G. Xiwu (2008)
Effects of insecticides on the fluidity of mitochondrial membranes of the diamondback moth, Plutella xylostella, resistant and susceptible to avermectin
Journal of Insect Science 8 (3), 1-9
Abstract: The effects of various insecticides on the fluidity of mitochondrial membranes and cross-resistance were investigated in the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae) using strains that were both resistant and susceptible to avermectin. The resistant strain of P. xylostella, AV-R, developed 1078-fold resistance to avermetins with a high level of cross-resistance to the analogs of avermectins, ivermectin and emamectin benzoate. It had more than 1000 times greater resistance when compared with the avermectin-susceptible strain, XH-S. Mitochondrial membrane fluidity was measured by detecting fluorescence polarization using DPH (1,6-Diphenyl -1,3,5-hexatriene) as the fluorescence probe. Abamectin, emamectin benzoate, ivermectin, cypermethrin and fenvalerate decreased the fluidity of mitochondrial membranes in the XH-S strain at 25°C. However, fipronil and acephate did not change the fluidity of mitochondrial membrane when the concentration of these insecticides was 1×10⁻⁴ mol/L. Membrane fluidity increased as the temperature increased. The thermotropic effect on the polarization value of DPH increased as the insecticide concentration was increased. There was a significant difference of mitochondrial membrane fluidity between both XH-S and AV-R when temperature was less than 25°C and no difference was observed when the temperature was more than 25°C. The low-dose abamectin (0.11 mg/L) in vivo treatment caused a significant change of membrane fluidity in the XH-S strain and no change in the AV-R strain. However, a high-dose abamectin (11.86 mg/L) resulted in 100% mortality of the XH-S strain. In vivo treatment may cause a significant change of membrane fluidity in the AV-R strain.
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Link to article at publishers website
Database assignments for author(s): Xi-Wu Gao

Research topic(s) for pests/diseases/weeds:
control - general
pesticide resistance of pest

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Plutella xylostella