HOST SPECTRUM OF BACILLUS-THURINGIENSIS

The known host range of Bacillus thuringiensis (Bt) is constantly expanding with the large amount of commercial interest and the extensive screening programs presently in progress. Although many strains are toxic to lepidoptem, other strains are known which are toxic to beetles, dipteran larvae especially mosquitoes, lice, mites and nematodes. The crystal or delta-endotoxin and the exotoxin or thuringiensin are the best known toxins, but there are other toxins, as yet unidentified, responsible for the pathogenicity to some hosts e.g. lice.