J. Econ. Entomol. 90(3): 732-741 (1997) ABSTRACT A colony of Plutella xylostella (L.), established from crucifer fields in Florida, was used to investigate resistance to Bacillus thuringiensis Berliner subsp. kurstaki. From an initial level of >I,500-fold. resistance fell within 3 generations in the absence of selection to =300-fold compared with susceptible larvae. Unlike previous cases of res...

This minireview discusses the risks to humans and large mammals associated with the use of Bacillus thuringiensis var. kurstaki (Btk) in forest, agricultural and urban environments. The first subspecies used for insect control was Bacillus thuringiensis subsp. thuringiensis (Btt), known at the time as Bt Berliner. Much of the early work done with Bt does not identify the subspecies. Btk is regi...

Trees in the genus Populus can provide substantial commercial and ecological benefits, including sustainable alternatives to traditional forestry. Realization of this potential requires intensive management, but damage by defoliating insects can severely limit productivity in such systems. Two approaches to limiting these losses include cultivation of poplar varieties with inherent resistance t...

The screening of Bacillus thuringiensis (Bt) Cry proteins with high potential to control insect pests has been the goal of numerous research groups. In this study, we evaluated six monogenic Bt strains (Bt dendrolimus HD-37, Bt kurstaki HD-1, Bt kurstaki HD-73, Bt thuringiensis 4412, Bt kurstaki NRD-12 and Bt entomocidus 60.5, which codify the cry1Aa, cry1Ab, cry1Ac, cry1Ba, cry1C, cry2A genes ...

In sporulating cultures of Bacillus thuringiensis subsp. yunnanensis HD977, two cell types are observed: cells forming only spores and cells forming only crystals. Curing analysis suggested that the crystal proteins are plasmid encoded. Through plasmid transfer experiments, it was established that a 103-MDa plasmid is involved in the crystal production. Conjugal transfer of this plasmid to Cry-...

Diverse isolates from a world-wide collection of Bacillus thuringiensis were classified based on phenotypic profiles resulting from six biochemical tests; production of amylase (T), lecithinase (L), urease (U), acid from sucrose (S) and salicin (A), and the hydrolysis of esculin (E). Eighty two isolates representing the 15 most common phenotypic profiles were subjected to phylogenetic analysis ...

This paper reports the isolation and identification of chitinase-producing Bacillus from chitin-containing wastes, production of a thermostable and alkaline chitinasese, and enzyme characterization. Bacillus thuringiensis subsp. kurstaki HBK-51 was isolated from soil and was identified. Chitinase was obtained from supernatant of B. thuringiensis HBK-51 strain and showed its optimum activity at ...

We report the sequences of nine novel Bacillus cereus group bacteriophages: DIGNKC, Juglone, Nemo, Nigalana, NotTheCreek, Phrodo, SageFayge, Vinny, and Zuko. These bacteriophages are double-stranded DNA-containing Myoviridae isolated from soil samples using B. thuringiensis subsp. kurstaki as the host bacterium.

We developed a process of producing a dead-spore Bacillus thuringiensis Berliner var. kurstaki HD-1 formulation, Toarow CT, and studied several aspects t o improve the productivity of crystal toxin and the insecticidal potency after sterilization to kill spores. The production of cell mass or crystal toxin was highly influenced by aeration and agitation of the culture. The culture broth, within...