INFLUENCE OF CRYSTAL PROTEIN-COMPOSITION OF BACILLUS-THURINGIENSIS STRAINS ON CROSS-RESISTANCE IN INDIANMEAL MOTHS (LEPIDOPTERA, PYRALIDAE)

Cross-resistance spectra of colonies of Plodia interpunctella (Hubner) resistant to strains of Bacillus thuringiensis Berliner subspp. kurstaki, aizawai, and entomocidus reflected the toxin composition of the B. thuringiensis isolates used for selection. Subsp. kurstaki caused relatively narrow-spectrum resistance to CryIA(b) and CryIA(c) toxins. The subspp. aizawai and entomocidus strains caused broader-spectrum resistance to CryIA(a), CryIA(b), CryIA(c), CryIB, CryIC, and CryIIA toxins. Thus, some isolates of subspp. aizawai and entomocidus can elicit resistance to half of the known B. thuringiensis toxins active against Lepidoptera.