Abstract
Insecticidal activities of sporulated cultures of the HD-1 and NRD-12 strains of Bacillus thuringiensis subsp. kurstaki were compared against four species of defoliating forest lepidopterans in diet-incorporation assays. There was no difference in LC 50 between the two strains to larvae of spruce budworm ( Choristoneura fumiferana), gypsy moth ( Lymantria dispar), eastern hemlock looper ( Lambdina fiscellaria fiscellaria), and whitemarked tussock moth ( Orgyia leucostigma), whether expressed as total alkaline soluble protein, activated toxin protein, or International Units as determined by bioassay against Trichoplusia ni. Both strains were consistently more toxic than HD-1-S-1980 when compared on the basis of alkali-soluble protein, but not on the basis of activated toxin or International Units. Hybridization of genomic DNA after restriction with HindIII revealed the presence of all three cryIA toxin genes in each of the isolates used in this study, including HD-1-S-1980, which was previously reported to have lost the cryIA(b) gene.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
