Entomopathogenic spore-formers from soil samples of mosquito habitats in northern Nigeria.

Spore-forming bacteria, isolated from bottom soil samples of periodical mosquito-breeding places in Kaduna, N. Nigeria, were tested for mosquito pathogenicity. Culex pipiens autogenicus was used for this screening. Five strains, all of the Bacillus thuringiensis group, were active in 85 isolates from 32 samples. The isolates were from three different serotypes (H-14, H-5a5c, and H-8a8b). The activity, compared with the SIP standard, was in the known limits of B. thuringiensis israelensis.