Study on the isolation and identification of Bacillus thuringiensis in soil samples from Yakushima Island (I) serological identification and flora

摘要

Yakushima Island is located south of Kyushu ISland. Nature is well preserved on this island. Since B. thuringiensis strains have been effectively isolated in soils from southern Asia, we tried to isolate B. thuringiensis and identify it by H-serotype. Based on these results, the flora of B. thuringiensis is discussed in this study. 1)Soil samples from 177 Spots in 35 sections of Yakushima Island were investigated and 3,955 strains belonging to Bacillus cereus from 68,153 Sporeforming bacterial strains were microscopically determined. Lastly, 53 B. thuringiensis isolates were serologically investigated. 2) Based on the H-serotyping results, 24 strains of serovar kurstaki, 14 strains of serovar galleriae and 6 strains of serovar sumiyoshicnsis were identified as dominant strains. This result indicates that the B. thuringiensis flora in the Yakushima Island is relatively unique.