The toxic action of cultures of Bacillus cereus and Bacillus thuringiensis on honey bees (Apis mellifera)
Zeitschrift für Pflanzenkrankheiten und Pflanzenschutz 80(8): 483-486
The effect of whole non-sporulated cultures of B. cereus (strain C-47) and B. thuringiensis (strain 1/5 and 111/36) and of fractions of the culture filtrate has been tested an honey bees (Apis mellifera). Two fractions have been found to be toxic for adult bees alter oral administration: 1. the well-known thermostable exotoxin („ß-exotoxin"), evidently a nucleoside, which was produced here only by strain 1/5 of B. thusingiensis (serotype H1); 2. a thermolabile exotoxin („α-exotoxin"?) probably proteinic in nature, which was produced by all strains tested. Only the latter thermolabile exotoxin was inactivated during the process of sporulation. Because sporulated cultures of B. cereus strain C-47 and B. thuringiensis strain 111/36 (serotype H3) contain no longer an insecticidal exotoxin, they are not harmful for bees.