This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Petras, S. F. Articles by Casida, L. E. Search for Related Content PubMed PubMed Citation Articles by Petras, S. F. Articles by Casida, L. E., Jr. Agricola Articles by Petras, S. F. Articles by Casida, L. E.

 Previous Article  |  Next Article 

Appl Environ Microbiol. 1985 December; 50(6): 1496-1501
Copyright © 1985, American Society for Microbiology. All Rights Reserved.

Survival of Bacillus thuringiensis Spores in Soil

Microbiology Program, The Pennsylvania State University, University Park, Pennsylvania 16802

ABSTRACT

Bacillus thuringiensis spores and parasporal crystals were incubated in natural soil, both in the laboratory and in nature. During the first 2 weeks, the spore count decreased by approximately 1 log. Thereafter, the number of spore CFU remained constant for at least 8 months. B. thuringiensis did not lose its ability to make the parasporal crystals during its residence in soil. Spore survival was similar for a commercial spore-crystal preparation (the insecticide) and for laboratory-grown spores. In contrast to these results, spores that were produced in situ in soil through multiplication of added vegetative cells survived for only a short time. For spore additions to soil, variations in soil pH had little effect on survival for those spores that survived the first 2 weeks of incubation. Also without effect were various pretreatments of the spores before incubation in soil or nutritional amendment or desiccation of the soil. Remoistening of a desiccated soil, however, caused a decrease in spore numbers. Spores incubated in soil in the field did not show this, but the degree of soil desiccation in nature probably never reached that for the laboratory samples. The good survival of B. thuringiensis spores after the first 2 weeks in soil seemed to be a result of their inability to germinate in soil. We found no evidence for the hypothesis that rapid germination ability for spores in soil conferred a survival advantage.

^* Corresponding author.

Paper no. 7144 in the journal series of the Pennsylvania Agriculture Experiment Station.

This article has been cited by other articles:

• Schnepf, E., Crickmore, N., Van Rie, J., Lereclus, D., Baum, J., Feitelson, J., Zeigler, D. R., Dean, D. H. (1998). Bacillus thuringiensis and Its Pesticidal Crystal Proteins. Microbiol. Mol. Biol. Rev. 62: 775-806 [Abstract] [Full Text]