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A SAMPLING SYSTEM FOR ESTIMATING EGG AND LARVAL POPULATIONS OF AGROMYZA FRONTELLA (DIPTERA: AGROMYZIDAE) IN ALFALFA12

Published online by Cambridge University Press:  31 May 2012

D. G. Harcourt  and
M. R. Binns
D. G. Harcourt
Affiliation:
Ottawa Research Station, Agriculture Canada, Ottawa K1A 0C6
M. R. Binns
Affiliation:
Engineering and Statistical Research Institute, Agriculture Canada, Ottawa K1A 0C6
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Abstract

During 1977, a detailed study was undertaken to develop efficient sampling procedures for estimating egg and larval populations of the alfalfa blotch leafminer, Agromyza frontella (Rond.), in Vernal alfalfa. Distributions of the stages within and between stems were contagious and stem totals tended to follow negative binomial distributions. Within stems, the density of eggs and larval mines increased exponentially from base to tip. Taking these patterns and the costs of sampling into account, and using the relevant components of variance, four leaves taken systematically from a single stem is proposed as the appropriate sample unit for both eggs and mines. On this basis, 200 stems per field will give adequate precision (less than 10% of the mean with confidence probability 90%) for population estimates. However, the propensity of the leafminer to prefer the middle leaflet to the basal leaflets in the approximate ratio 3:4:3 suggests that sampling costs may be further reduced by restricting counts to the middle leaflet and raising them by a factor of 2.5.

Type
Articles
Information
The Canadian Entomologist , Volume 112 , Issue 4 , 01 April 1980 , pp. 375 - 385
Copyright
Copyright © Entomological Society of Canada 1980

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References

Bereza, K. 1976. Alfalfa blotch leafminer. Can. Agric. Insect Pest Rev. 54: 23.Google Scholar
Bliss, C. E. and Owen, A. R. G.. 1958. Negative binomial distributions with a common k. Biometrika 45: 37–58.CrossRefGoogle Scholar
Cochran, W. G. 1963. Sampling techniques, 2nd ed., Wiley, New York.Google Scholar
Guppy, J. C. and Harcourt, D. G.. 1977. The alfalfa blotch leaf miner in eastern Ontario, 1977. Proc. 14th Ann. Northeast Invitational Alfalfa Insects Conf., Burlington, Vermont.Google Scholar
Harcourt, D. G. 1973. Agromyza frontella (Rond.) (Diptera: Agromyzidae) a pest of alfalfa new to Canada. Ann. ent. Soc. Queb. 18: 49–51.Google Scholar
Harcourt, D. G., Mukerji, M. K., and Guppy, J. C.. 1974. Estimation of egg populations of the alfalfa weevil, Hypera postica (Coleoptera: Curculionidae). Can. Ent. 106: 337–347.CrossRefGoogle Scholar
Helgeson, R. G. 1976. Biology and management of the alfalfa blotch leafminer. Rep. 25th Alfalfa Improvement Conf., Cornell Univ., Ithaca, N.Y.Google Scholar
Mellors, W. K. and Helgesen, R. G.. 1978. A life table analysis for the alfalfa blotch leafminer, Agromyza frontella, in central New York. Proc. 15th Ann. Northeast Invitational Alfalfa Insects Conf., Purdue Univ., Lafayette, Indiana.Google Scholar
Miller, D. E. and Jensen, G. L.. 1970. Agromyzid alfalfa leaf miners and their parasites in Massachusetts. J. econ. Ent. 63: 1337–1338.CrossRefGoogle Scholar
Morris, R. F. 1955. The development of sampling techniques for forest insect defoliators, with particular reference to the spruce budworm. Can. J. Zool. 33: 225–294.CrossRefGoogle Scholar
Sampford, M. R. 1962. An Introduction to Sampling Theory. Oliver & Boyd, Edinburgh.Google Scholar
Snedecor, G. W. and Cochran, W. G.. 1967. Statistical Methods. Iowa State University Press, Ames.6th ed.Google Scholar
Taylor, L. R. 1961. Aggregation, variance and the mean. Nature, Lond. 189: 732–735.CrossRefGoogle Scholar
Thompson, L. S. 1974. Alfalfa blotch leafminer, Agromyza frontella (Rond.). Can. Agric. Insect Pest Rev. 52: 5.Google Scholar