Activity of spores and extracellular proteins from six Cry+ strains and a Cry- strain of Bacillus thuringiensis subsp. kurstaki against the western spruce budworm, Choristoneura occidentalis (Lepidoptera: Tortricidae). - Kalmykova, Galina; Burtseva, Ljudmila; Milne, Ross; van Frankenhuyzen, Kees (Canadian Journal of Microbiology, 2009)