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Evaluation of insecticides in field-control simulators and standard laboratory bioassays against resistant and susceptible Bemisia tabaci (Homoptera: Aleyrodidae) from Sudan

Published online by Cambridge University Press:  10 July 2009

Mark Rowland*
Affiliation:
AFRC Institute of Arable Crops Research, Rothamsted Experimental Station, Harpenden, UK
Barbara Hackett
Affiliation:
AFRC Institute of Arable Crops Research, Rothamsted Experimental Station, Harpenden, UK
Mary Stribley
Affiliation:
AFRC Institute of Arable Crops Research, Rothamsted Experimental Station, Harpenden, UK
*
Dr M. Rowland, AFRC Institute of Arable Crops Research, Rothamsted Experimental Station, Harpenden, Herts, AL5 2JQ, UK.

Abstract

Cypermethrin, profenofos, and a mixture of these insecticides were evaluated against resistant and susceptible whitefly, Bemisa tabaci Gennadius, from Sudan using (a) laboratory technology which simulates the aerial spraying of whitefly infestations on cotton crops, and (b) standard residue-bioassays. Simulator tests in which adult cohorts were given a single insecticide treatment produced results that were unexpected on the basis of standard bioassay data. Resistance to cypermethrin, for example, was expressed in the bioassays but not in the simulator, resistance to profenofos was expressed both in bioassays and in the simulator, resistance to the mixture was expressed in the simulator but in the bioassay the chemicals acted synergistically and there was no resistance. Repeated treatment of resistant populations, comprised of all life stages, over three generations gave further unpredicted results: cypermethrin failed to contact larvae on the under surfaces of leaves and hence did not prevent population growth; profenofos sprayed at field rates controlled all life-stages (despite the expression of resistance) provided the insecticide vapour was not dissipated. An alternation of cypermethrin and profenofos – cypermethrin timed against maximum adult emergence and profenofos timed to coincide with high larval densities – gave the best control. The disparities between the simulator experiments and standard bioassays suggest that techniques simulating the field treatment of all life-stages are better suited for evaluating the practical significance of resistance and potential curative strategies.

Type
Research Paper
Copyright
Copyright © Cambridge University Press 1991

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References

Byrne, F.J. & Devonshire, A.L. (in press) In vivo inhibition of esterase and acetylcholinesterase activities by profenofos treatments in the tobacco whitefly Bemisia tabaci; implications for routine biochemical monitoring of these enzymes. Pesticide Biochemistry & Physiology.Google Scholar
Denholm, I., Sawicki, R.M. & Farnham, A.F. (1987) Laboratory simulation of selection for resistance. pp. 138149. in Ford, M.G., Holloman, D.W., Kambay, B.P.S. & Sawicki, R.M. (Eds) Combating resistance to xenobiotics. England, Ellis Horwood.Google Scholar
Dennehy, T.J., Granett, J. & Leigh, T.F. (1983) Relevance of slide-dip and residual bioassay comparisons to detection of resistance in spider mites. Journal of Economic Entomology 76, 12251230.CrossRefGoogle Scholar
Dittrich, V., Hassan, S.O. & Ernst, G.H. (1985) Sudanese cotton and the whitefly: a case study of the emergence of a new primary pest. Crop Protection 4, 161176.CrossRefGoogle Scholar
Dittrich, V., Ernst, G.H., Ruesch, O. & Uk, S. (1990) Resistance mechanisms analysed in whitefly populations from the Sudan, Turkey, Guatemala and Nicaragua. Journal of Economic Entomology 83, 16651670.CrossRefGoogle Scholar
Ishaaya, I., Mendelson, Z., Ascher, K.R.S. & Casida, J.E. (1987) Cypermethrin synergism by pyrethroid esterase inhibitors in adults of the whitefly Bemisia tabaci. Pesticide Biochemistry and Physiology 28, 155162.CrossRefGoogle Scholar
McKenzie, J.A. & Whitten, M.J. (1982) Selection for insecticide resistance in the Australian sheep blowfly Lucilia cuprina. Experimentia 38, 8485.CrossRefGoogle ScholarPubMed
McKenzie, J.A. & Whitten, M.J. (1984) Estimation of the relative viabilities of insecticide resistance genotypes of the Australian sheep blowfly Lucilia cuprina. Australian Journal of Biological Science 37, 4552.CrossRefGoogle Scholar
Milio, J.F., Koehler, P.O & Patterson, R.S. (1987) Evaluation of three methods for detecting chlorphyrifos resistance in German cockroach populations. Journal of Economic Entomology 80, 4446.CrossRefGoogle Scholar
Rawlings, P., Davidson, G., Sakai, R.K., Rathor, H.R., Aslamkhan, M. & Curtis, C.F. (1981) Field measurement of the effective dominance of an insecticide resistance in anopheline mosquitoes. Bulletin of the World Health Organization 59, 631640.Google Scholar
Rowland, M., Pye, B.J., Stribley, M., Hackett, B., Denholm, I. & Sawicki, R.M. (1990) Laboratory apparatus and techniques for the rearing and insecticidal treatment of whitefly Bemisia tabaci under simulated field conditions. Bulletin of Entomological Research 80, 209216.CrossRefGoogle Scholar