The toxicity of a collection of 1400 isolates ofBacillus thuringiensiswas assessed against the LepidopteraSpodoptera frugiperda, Anti-carsia gemmantalisandPlutella xylostella. Twenty seven isolates showed toxicity to the larvae of these insects with three isolates dem-onstrating significantly greater potency than the standard strain against Lepidoptera,B. thuringiensisserovar kurstakiHD1. These
isolates were all found to produce bipyramidal crystals and major spore-associated protein bands of approximately 130 and 65 kDa, con-sistent with the detection of at least onecry1and onecry2family gene in each. The high level of insecticidal activity of these isolates
makes them excellent candidates for further development for use in the field.
2006 Elsevier Inc. All rights reserved.