| Abstrakt: |
In a laboratory assay in which synthetic media were used, several varieties of Bacillus thuringiensishave been tested for pathogenicity for larvae of the spruce budworm, Choristoneura fumiferana. The toxicity of nearly pure parasporal inclusions (crystals) and precipitated parasporal inclusion protein was also investigated. The varieties alesti, berliner, entomocidus, sotto, and galleriaewere highly to moderately pathogenic; the varieties kenyaeand dendrolimuswere less so, and the variety finitimuswas only slightly pathogenic. Although ingestion of crystals and precpitated crystal protein led to inhibition of feeding by larvae, the most pathogenic preparations were those that contained both spores and crystals. |
