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Mushtaq Ahmad - One of the best experts on this subject based on the ideXlab platform.
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observed potentiation between pyrethroid and organophosphorus insecticides for the management of spodoptera litura lepidoptera noctuidae
Crop Protection, 2009Co-Authors: Mushtaq AhmadAbstract:Abstract Mixtures of pyrethroids plus organophosphates were assessed for their potentiation in resistant field populations of Spodoptera litura from Pakistan by using a leaf-dip bioassay method. Cypermethrin, alphacypermethrin, bifenthrin, deltamethrin, and cyfluthrin exhibited potentiation by ethion. Mixtures of deltamethrin + triazophos and cyfluthrin + methamidophos also showed potentiation. Cypermethrin in combination with profenofos or chlorpyrifos produced an antagonism.
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potentiation between pyrethroid and organophosphate insecticides in resistant field populations of cotton bollworm helicoverpa armigera lepidoptera noctuidae in pakistan
Pesticide Biochemistry and Physiology, 2008Co-Authors: Mushtaq AhmadAbstract:The combined action of pyrethroids plus organophosphates was assessed on putatively resistant field populations of Helicoverpa armigera from Pakistan by using a leaf-dip bioassay. Ethion showed a good potentiation with bifenthrin, lambdacyhalothrin, cyfluthrin, betacyfluthrin, fenpropathrin, esfenvalerate, fluvalenate and tralomethrin. Profenofos was potentiating with bifenthrin but additive with lambdacyhalothrin. Methyl parathion also exhibited potentiation with bifenthrin. Contrarily, quinalphos produced an antagonism with bifenthrin. Chlorpyrifos potentiated lambdacyhalothrin in one population but had an additive effect in the other. A strong potentiation of pyrethroids by ethion in some populations indicates that esteratic detoxification is a key mechanism involved in imparting resistance to pyrethroids in Pakistani H. armigera.
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susceptibility of pakistani populations of cotton aphid aphis gossypii homoptera aphididae to endosulfan organophosphorus and carbamate insecticides
Crop Protection, 2008Co-Authors: Mushtaq Ahmad, Iqbal M ArifAbstract:Abstract The Pakistani field populations of Aphis gossypii were assessed from 1996 to 2004 for their susceptibility to endosulfan, organophosphates (monocrotophos, dimethoate, profenofos, chlorpyrifos, quinalphos, parathion-methyl, pirimiphos-methyl and ethion) and carbamates (carbaryl, methomyl, thiodicarb, furathiocarb and carbosulfan) using a leaf-dip bioassay method. Generally, there was a very low resistance to endosulfan, monocrotophos, profenofos, chlorpyrifos, quinalphos, pirimiphos-methyl, carbaryl and methomyl, and a low to moderate resistance to dimethoate, parathion-methyl and thiodicarb. Some of the populations had a very high resistance to parathion-methyl, ethion and thiodicarb. However, no resistance was found to the carbamate aphidicides furathiocarb and carbosulfan. Correlation analysis demonstrated positive correlation of LC 50 s within but not between the two insecticide groups (1) endosulfan, profenofos, chlorpyrifos and parathion-methyl and (2) monocrotophos, dimethoate, pirimiphos-methyl, ethion, carbaryl, methomyl and thiodicarb. This pattern of cross-resistance among organophosphates and carbamates, which are normally considered to have the same mode of action, is very useful for devising an insecticide resistance management strategy to mitigate resistance problems in A. gossypii and deserve further investigation at the resistance mechanism level.
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potentiation antagonism of deltamethrin and cypermethrins with organophosphate insecticides in the cotton bollworm helicoverpa armigera lepidoptera noctuidae
Pesticide Biochemistry and Physiology, 2004Co-Authors: Mushtaq AhmadAbstract:The joint action of pyrethroids deltamethrin and cypermethrins in combination with organophosphates ethion, profenofos, chlorpyrifos, quinalphos, and triazophos was studied on putatively resistant field populations of Helicoverpa armigera from Pakistan by using a leaf-dip method. Ethion produced a good potentiation with deltamethrin, cypermethrin, alphacypermethrin, and zetacypermethrin, whereas profenofos, chlorpyrifos, quinalphos, and triazophos exhibited an antagonism with deltamethrin as well as cypermethrins. Implications of using mixtures for counteracting insecticide resistance are discussed.
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patterns of resistance to organophosphate insecticides in field populations of helicoverpa armigera in pakistan
Pesticide Science, 1999Co-Authors: Mushtaq Ahmad, Iqbal M Arif, Zahoor AhmadAbstract:The pattern of organophosphate resistance in field populations of Helicoverpa armigera (Hubner) was monitored in Pakistan from 1994 through 1997 using an IRAC leaf-dip method. Generally, moderate to high resistance was found to an orthophosphorate, monocrotophos and to a dithiophosphorate, ethion. Resistance to the commonly used thiophosphorates, chlorpyrifos and profenofos, was very low during 1994 and 1995 but showed an upward trend during 1996 and 1997. Resistance factors to the other thiophosphorates such as quinalphos, parathion-methyl, methamidophos and triazophos remained very low. Baseline lethal concentrations for ethion, methamidophos and triazophos were at least four to five times higher than those for the other organophosphates tested, suggesting their low intrinsic efficacy against H armigera.
Daniel B. Fragoso - One of the best experts on this subject based on the ideXlab platform.
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Insecticide use and organophosphate resistance in the coffee leaf miner Leucoptera coffeella (Lepidoptera: Lyonetiidae).
Bulletin of entomological research, 2002Co-Authors: Daniel B. Fragoso, Marcelo Coutinho Picanco, Raul Narciso C. Guedes, L. ZambolimAbstract:Increasing rates of insecticide use against the coffee leaf miner Leucoptera coffeella (Guerin-Meneville) and field reports on insecticide resistance led to an investigation of the possible occurrence of resistance of this species to some of the oldest insecticides used against it in Brazil: chlorpyrifos, disulfoton, ethion and methyl parathion. Insect populations were collected from ten sites in the state of Minas Gerais, Brazil and these populations were subjected to discriminating concentrations established from insecticide LC 99 s estimated for a susceptible standard population. Eight of the field-collected populations showed resistance to disulfoton, five showed resistance to ethion, four showed resistance to methyl parathion, and one showed resistance to chlorpyrifos. The frequency of resistant individuals in each population ranged from 10 to 93% for disulfoton, 53 to 75% for ethion, 23 to 76% for methyl parathion, and the frequency of resistant individuals in the chlorpyrifos resistant population was 35%. A higher frequency of individuals resistant to chlorpyrifos, disulfoton and ethion was associated with greater use of insecticides, especially other organophosphates. This finding suggests that cross-selection, mainly between organophosphates, played a major role in the evolution of insecticide resistance in Brazilian populations of L. coffeella . Results from insecticide bioassays with synergists (diethyl maleate, piperonyl butoxide and triphenyl phosphate) suggested that cytochrome P450-dependent monooxygenases may play a major role in resistance with minor involvement of esterases and glutathione S -transferases.
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seletividade de inseticidas a vespas predadoras de leucoptera coffeella guer menev lepidoptera lyonetiidae
Neotropical Entomology, 2001Co-Authors: Daniel B. Fragoso, R N C Guedes, Pedro Jusselinofilho, Reginaldo ProqueAbstract:Studies of relative toxicity of the organophosphate insecticides disulfoton, ethion, methyl-parathion e chlorpyrifos to the predatory wasps Brachygastra lecheguana Latreille, Polybia paulista Ihering e Protopolybia exigua Saussure and their prey, the coffee leaf-miner Leucoptera coffeella (Guerin-Meneville), were carried out in laboratory. The concentrations which killed 99% of individuals of L. coffeella were: 0.08; 83.95; 0.43; 0.07 mg i.a/cm2 of disulfoton, ethion, methyl-parathion and chlorpyrifos, respectively. These concentrations were used to assess the selectivity of insecticides in impregnated paper filter assays. Methyl-parathion and chlorpyrifos were highly toxic to these wasp species, while disulfoton and ethion were selective in their favour.
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protecao de plantas seletividade de inseticidas a vespas predadoras de leucoptera coffeella guer menev lepidoptera lyonetiidae
2001Co-Authors: Daniel B. Fragoso, Pedro Jusselinofilho, R N C GuedesAbstract:ABSTRACT - Studies of relative toxicity of the organophosphate insecticides disulfoton, ethion, methyl-parathion e chlorpyrifos to the predatory wasps Brachygastra lecheguana Latreille, Polybia paulista Ihering e Protopolybia exigua Saussure and their prey, the coffee leaf-miner Leucoptera coffeella (GuOrin-MŁneville), were carried out in laboratory. The concentrations which killed 99% of individualsof L. coffeella were: 0.08; 83.95; 0.43; 0.07 mg i.a/cm 2 of disulfoton, ethion, methyl-parathion andchlorpyrifos, respectively. These concentrations were used to assess the selectivity of insecticides inimpregnated paper filter assays. Methyl-parathion and chlorpyrifos were highly toxic to these waspspecies, while disulfoton and ethion were selective in their favour.KEY WORDS: Insecta, toxicity, natural enemies, coffee leaf-miner, organophosphates.RESUMO - Estudos de toxicidade relativa dos inseticidas organo-fosforados dissulfotom, etiom,paratiom-metilico e clorpirifos as vespas predadoras
L. Zambolim - One of the best experts on this subject based on the ideXlab platform.
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Insecticide use and organophosphate resistance in the coffee leaf miner Leucoptera coffeella (Lepidoptera: Lyonetiidae).
Bulletin of entomological research, 2002Co-Authors: Daniel B. Fragoso, Marcelo Coutinho Picanco, Raul Narciso C. Guedes, L. ZambolimAbstract:Increasing rates of insecticide use against the coffee leaf miner Leucoptera coffeella (Guerin-Meneville) and field reports on insecticide resistance led to an investigation of the possible occurrence of resistance of this species to some of the oldest insecticides used against it in Brazil: chlorpyrifos, disulfoton, ethion and methyl parathion. Insect populations were collected from ten sites in the state of Minas Gerais, Brazil and these populations were subjected to discriminating concentrations established from insecticide LC 99 s estimated for a susceptible standard population. Eight of the field-collected populations showed resistance to disulfoton, five showed resistance to ethion, four showed resistance to methyl parathion, and one showed resistance to chlorpyrifos. The frequency of resistant individuals in each population ranged from 10 to 93% for disulfoton, 53 to 75% for ethion, 23 to 76% for methyl parathion, and the frequency of resistant individuals in the chlorpyrifos resistant population was 35%. A higher frequency of individuals resistant to chlorpyrifos, disulfoton and ethion was associated with greater use of insecticides, especially other organophosphates. This finding suggests that cross-selection, mainly between organophosphates, played a major role in the evolution of insecticide resistance in Brazilian populations of L. coffeella . Results from insecticide bioassays with synergists (diethyl maleate, piperonyl butoxide and triphenyl phosphate) suggested that cytochrome P450-dependent monooxygenases may play a major role in resistance with minor involvement of esterases and glutathione S -transferases.
Marcelo Coutinho Picanco - One of the best experts on this subject based on the ideXlab platform.
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seletividade fisiologica de inseticidas a vespas predadoras hymenoptera vespidae de leucoptera coffeella lepidoptera lyonetiidae
BioAssay, 2009Co-Authors: Leandro Bacci, Marcelo Coutinho Picanco, Flavio Lemes Fernandes, Andre L B Crespo, Mateus R CamposAbstract:Conservation of natural enemies is an important component of integrated pest management. In this work, the selectivity of 11 insecticides used for management of Leucoptera coffeella (Guerin-Meneville) was studied to Protonectarina sylveirae (Saussure), Polybia scutellaris (White) and Protopolybia exigua (Saussure) (Hymenoptera: Vespidae). The insecticides were applied in concentrations corresponding to 50% and 100% of the field rates used for management of L. coffeella. The organophosphates (except to the 50% rate of ethion to P. scutellaris) were highly toxic to all three Vespidae species. Cartap was highly toxic to P. escutellaris and P. exigua but showed median selectivity to P. sylveirae. The pyrethroids cypermethrin, deltamethrin, betacyfluthrin, zetacypermethrin, and esfenvalerate were selective to at least one of wasp species. The mortality of P. scutelaris caused by ethion, cypermethrin, deltamethrin, betacyfluthrin and zetacypermethrin decreased when 50% of the recommended rates were used. This reduction was also observed for the mortality of P. exigua by permethrin and for the mortality of P. sylveirae by deltamethrin. P. sylveirae was the most tolerant species to cartap; P. scutellaris was the most tolerant to ethion, while P. exigua was more tolerant to pyrethroids than P. scutellaris and P. sylveirae. The results of this research indicate that pyrethroid insecticides are likely to be selective to predatory wasps in field settings given their overall selectivity in the conditions of extreme exposure of this study. The possible mechanisms underlying the selectivity of these compounds and the differential tolerance of the wasps are discussed.
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Insecticide use and organophosphate resistance in the coffee leaf miner Leucoptera coffeella (Lepidoptera: Lyonetiidae).
Bulletin of entomological research, 2002Co-Authors: Daniel B. Fragoso, Marcelo Coutinho Picanco, Raul Narciso C. Guedes, L. ZambolimAbstract:Increasing rates of insecticide use against the coffee leaf miner Leucoptera coffeella (Guerin-Meneville) and field reports on insecticide resistance led to an investigation of the possible occurrence of resistance of this species to some of the oldest insecticides used against it in Brazil: chlorpyrifos, disulfoton, ethion and methyl parathion. Insect populations were collected from ten sites in the state of Minas Gerais, Brazil and these populations were subjected to discriminating concentrations established from insecticide LC 99 s estimated for a susceptible standard population. Eight of the field-collected populations showed resistance to disulfoton, five showed resistance to ethion, four showed resistance to methyl parathion, and one showed resistance to chlorpyrifos. The frequency of resistant individuals in each population ranged from 10 to 93% for disulfoton, 53 to 75% for ethion, 23 to 76% for methyl parathion, and the frequency of resistant individuals in the chlorpyrifos resistant population was 35%. A higher frequency of individuals resistant to chlorpyrifos, disulfoton and ethion was associated with greater use of insecticides, especially other organophosphates. This finding suggests that cross-selection, mainly between organophosphates, played a major role in the evolution of insecticide resistance in Brazilian populations of L. coffeella . Results from insecticide bioassays with synergists (diethyl maleate, piperonyl butoxide and triphenyl phosphate) suggested that cytochrome P450-dependent monooxygenases may play a major role in resistance with minor involvement of esterases and glutathione S -transferases.
R N C Guedes - One of the best experts on this subject based on the ideXlab platform.
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seletividade de inseticidas a vespas predadoras de leucoptera coffeella guer menev lepidoptera lyonetiidae
Neotropical Entomology, 2001Co-Authors: Daniel B. Fragoso, R N C Guedes, Pedro Jusselinofilho, Reginaldo ProqueAbstract:Studies of relative toxicity of the organophosphate insecticides disulfoton, ethion, methyl-parathion e chlorpyrifos to the predatory wasps Brachygastra lecheguana Latreille, Polybia paulista Ihering e Protopolybia exigua Saussure and their prey, the coffee leaf-miner Leucoptera coffeella (Guerin-Meneville), were carried out in laboratory. The concentrations which killed 99% of individuals of L. coffeella were: 0.08; 83.95; 0.43; 0.07 mg i.a/cm2 of disulfoton, ethion, methyl-parathion and chlorpyrifos, respectively. These concentrations were used to assess the selectivity of insecticides in impregnated paper filter assays. Methyl-parathion and chlorpyrifos were highly toxic to these wasp species, while disulfoton and ethion were selective in their favour.
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protecao de plantas seletividade de inseticidas a vespas predadoras de leucoptera coffeella guer menev lepidoptera lyonetiidae
2001Co-Authors: Daniel B. Fragoso, Pedro Jusselinofilho, R N C GuedesAbstract:ABSTRACT - Studies of relative toxicity of the organophosphate insecticides disulfoton, ethion, methyl-parathion e chlorpyrifos to the predatory wasps Brachygastra lecheguana Latreille, Polybia paulista Ihering e Protopolybia exigua Saussure and their prey, the coffee leaf-miner Leucoptera coffeella (GuOrin-MŁneville), were carried out in laboratory. The concentrations which killed 99% of individualsof L. coffeella were: 0.08; 83.95; 0.43; 0.07 mg i.a/cm 2 of disulfoton, ethion, methyl-parathion andchlorpyrifos, respectively. These concentrations were used to assess the selectivity of insecticides inimpregnated paper filter assays. Methyl-parathion and chlorpyrifos were highly toxic to these waspspecies, while disulfoton and ethion were selective in their favour.KEY WORDS: Insecta, toxicity, natural enemies, coffee leaf-miner, organophosphates.RESUMO - Estudos de toxicidade relativa dos inseticidas organo-fosforados dissulfotom, etiom,paratiom-metilico e clorpirifos as vespas predadoras