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AN IMPROVED TECHNIQUE FOR DOSING LARVAE OF THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE), WITH MEASURED QUANTITIES OF BACILLUS THURINGIENSIS VAR. KURSTAKI

Published online by Cambridge University Press:  31 May 2012

A. Moore
Affiliation:
Forest Pest Management Institute, Canadian Forestry Service, Sault Ste. Marie, Ontario P6A 5M7
O. N. Morris
Affiliation:
Forest Pest Management Institute, Canadian Forestry Service, Sault Ste. Marie, Ontario P6A 5M7

Extract

Bioassays of Bacillus thuringiensis (Bt.) are commonly performed by applying a serial dilution of the test sample to either foliage or artificial diet (Burges and Thompson 1971). In these assays the ingested dose is not measured directly, but is assumed to be proportional to the concentration of the sample applied to the diet. This assumption is valid only if the total amount of food ingested during the experiment is the same at all dosage levels. However, this assumption may not be true because Bt. inhibits feeding of some lepidoptera larvae (Burges and Thompson 1971). Furthermore, artificial diets usually contain nutrients and possibly antimicrobial agents which may interact with Bt.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1982

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References

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