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ABSENCE OF FATTY ACID GERMINATION INHIBITORS FOR CONIDIA OF BEAUVERIA BASSIANA ON THE INTEGUMENT OF THE BARK BEETLE DENDROCTONUS PONDEROSAE (COLEOPTERA: SCOLYTIDAE)

Published online by Cambridge University Press:  31 May 2012

D.W.A. Hunt
Affiliation:
Centre for Pest Management, Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6

Extract

Ether extracts from Eurygaster integriceps (Evlakhova and Chekhourina 1962) and Bombyx mori (Koidsumi 1957) have been found to inhibit germination of conidia of the white muscardine fungus, Beauveria bassiana, and of Aspergillus flavus, respectively. Free fatty acids, such as caprylic acid, which inhibit the germination of B. bassiana conidia (Smith and Grula 1981), have been found on the cuticle of several insects (Smith and Grula 1982; Saito and Aoki 1983). However, Smith and Grula (1982) found that the toxicity of free fatty acids to B. bassiana conidia in vitro is dependent on the nutritional conditions present. The germination of B. bassiana conidia onthe integument of the mountain pine beetle, Dendroctonus ponderosae, is seldom observed without nutrient enhancement (Hunt et al. 1984). My objective was to determine whether the relative absence of conidial germination on D. ponderosae cuticle is due in part to the action of toxic free fatty acids.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1986

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References

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