Among several methods used to estimate the efficacy of an acaricide is the Drummond adult test, based on formulas which permit the assessment of the reproductive capacity of treated female ticks in comparison with controls. A constant value of 20,000 is normally used in these formulas,
because this figure approximates the number of larvae that will hatch from 1 g of eggs. In laboratory studies conducted on large numbers of ticks, egg counting is a time-consuming and fastidious operation. Therefore, in quantitative studies, sampling techniques are more convenient. The use
of the weight of egg masses laid by ixodids is adequate because eggs congregate in clusters. Experimental results have demonstrated that the analysis of the mean daily weight of egg aliquots in comparison with actual counts, from the 1st to the 20th d of oviposition, did not permit rejection
of the hypothesis that 20,000 would be a representative number of eggs contained in 1 g. When aliquots were weighed only on the 20th or the 30th d of the oviposition-incubation period, and the results were analyzed in comparison with egg counts, the value of 20,000 no longer was reliable to
express the number of Boophilus micnlpllls (Canestrini) eggs contained in 1 g.
Document Type: Research Article
Publication date: February 1, 1998
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Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.