Role of glutathione s-transferase in organophosphorus resistance of diamondback moth larvae

Sun C.N., . and Kao C.H., . and Chiang F.M., . (1990) Role of glutathione s-transferase in organophosphorus resistance of diamondback moth larvae. [Proceedings Paper]

Diamondback moth Plutella xylostella L. an insect pest of cruciferous crops has become resistant to all major groups of synthetic insecticides. In an attempt to clarify the role of glutathione S-transferase in organophosphorus resistance we measured the in vitro degradation by larval homogenate of susceptible and resistant diamondback moth of some organophosphorus insecticides e.g. methyl parathion parathion methyl paraoxon paraoxon diazinon malathion and azinphosmethyl. The action of glutathione S-transferase was confirmed by the requirement of reduced glutathione as cofactor and the inhibitory effect of diethylmaleate and N-ethylmaleimide. The involvement of other detoxication enzymes microsomal monooxygenases and hydrolases was also examined with pertinent cofactors and inhibitors. Glutathione conjugation was the major detoxifying reaction for all organophosphorus insecticides tested exept malathion. Carboxylesterase was apparently responsible for the degradation of malathion. Considerably higher degradation rates of both methyl parathion and aprathion were found in the resistant than the susceptaible strains. However degradation of methyl paraoxon and paraoxon bioactivated metabolits of methyl parathion and parathion by glutathione S-transferase of these strains was much reduced. While resistance to pyrethroids and some benzoylphenyl ureas in this insect has been attributed to enhanced microsomal oxidation the glutathione conjugation of organophosphorus insecticides observed in the present study offers an explanation of a lack of cross resistance betweem organophosphorus compounds and pyrethroids/benzoylphenyl ureas. These insecticides can be alternatively used in the insecticide management programs for diamondback moth

Full text available from:

Abstract

Diamondback moth Plutella xylostella L. an insect pest of cruciferous crops has become resistant to all major groups of synthetic insecticides. In an attempt to clarify the role of glutathione S-transferase in organophosphorus resistance we measured the in vitro degradation by larval homogenate of susceptible and resistant diamondback moth of some organophosphorus insecticides e.g. methyl parathion parathion methyl paraoxon paraoxon diazinon malathion and azinphosmethyl. The action of glutathione S-transferase was confirmed by the requirement of reduced glutathione as cofactor and the inhibitory effect of diethylmaleate and N-ethylmaleimide. The involvement of other detoxication enzymes microsomal monooxygenases and hydrolases was also examined with pertinent cofactors and inhibitors. Glutathione conjugation was the major detoxifying reaction for all organophosphorus insecticides tested exept malathion. Carboxylesterase was apparently responsible for the degradation of malathion. Considerably higher degradation rates of both methyl parathion and aprathion were found in the resistant than the susceptaible strains. However degradation of methyl paraoxon and paraoxon bioactivated metabolits of methyl parathion and parathion by glutathione S-transferase of these strains was much reduced. While resistance to pyrethroids and some benzoylphenyl ureas in this insect has been attributed to enhanced microsomal oxidation the glutathione conjugation of organophosphorus insecticides observed in the present study offers an explanation of a lack of cross resistance betweem organophosphorus compounds and pyrethroids/benzoylphenyl ureas. These insecticides can be alternatively used in the insecticide management programs for diamondback moth

[error in script]

Item Type:	Proceedings Paper
Additional Information:	4 tables 22 ref.; Summary En
AGROVOC Term:	PLUTELLA XYLOSTELLA
AGROVOC Term:	TRANSFERASAS
AGROVOC Term:	RESISTENCIA QUIMICA
AGROVOC Term:	COMPUESTO ORGANICO DEL FOSFORO/ CONTROL DE INSECTOS
AGROVOC Term:	LARVAS
AGROVOC Term:	INSECTICIDAS
Geographical Term:	MALAYSIA
Depositing User:	Ms. Norfaezah Khomsan
Last Modified:	24 Apr 2025 05:26
URI:	http://webagris.upm.edu.my/id/eprint/14951

Actions (login required)

View Item