This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hunter, P. J.
Right arrow Articles by Whipps, J. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hunter, P. J.
Right arrow Articles by Whipps, J. M.
Agricola
Right arrow Articles by Hunter, P. J.
Right arrow Articles by Whipps, J. M.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, October 2006, p. 6452-6460, Vol. 72, No. 10
0099-2240/06/$08.00+0     doi:10.1128/AEM.00313-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Differences in Microbial Activity and Microbial Populations of Peat Associated with Suppression of Damping-Off Disease Caused by Pythium sylvaticum

Paul J. Hunter,* Geoff M. Petch, Leo A. Calvo-Bado,{dagger} Tim R. Pettitt,{ddagger} Nick R. Parsons,§ J. Alun W. Morgan, and John M. Whipps

Warwick HRI, University of Warwick, Wellesbourne, Warwick CV35 9EF, United Kingdom

Received 8 February 2006/ Accepted 16 July 2006

The microbiological characteristics associated with disease-suppressive peats are unclear. We used a bioassay for Pythium sylvaticum-induced damping-off of cress seedlings to identify conducive and suppressive peats. Microbial activity in unconditioned peats was negatively correlated with the counts of P. sylvaticum at the end of the bioassay. Denaturing gradient gel electrophoresis (DGGE) profiling and clone library analyses of small-subunit rRNA gene sequences from two suppressive and two conducive peats differed in the bacterial profiles generated and the diversity of sequence populations. There were also significant differences between bacterial sequence populations from suppressive and conducive peats. The frequencies of a number of microbial groups, including the Rhizobium-Agrobacterium group (specifically sequences similar to those for the genera Ochrobactrum and Zoogloea) and the Acidobacteria, increased specifically in the suppressive peats, although no single bacterial group was associated with disease suppression. Fungal DGGE profiles varied little over the course of the bioassay; however, two bands associated specifically with suppressive samples were detected. Sequences from these bands corresponded to Basidiomycete yeast genera. Although the DGGE profiles were similar, fungal sequence diversity also increased during the bioassay. Sequences highly similar to those of Cryptococcus increased in relative abundance during the bioassay, particularly in the suppressive samples. This study highlights the importance of using complementary approaches to molecular profiling of complex populations and provides the first report that basidiomycetous yeasts may be associated with the suppression of Pythium-induced diseases in peats.


* Corresponding author. Mailing address: Warwick HRI, University of Warwick, Wellesbourne, Warwickshire CV35 9EF, United Kingdom. Phone: 44 24-7657-5140. Fax: 44 24-765-74500. E-mail: paul.hunter{at}warwick.ac.uk.

{dagger} Present address: Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, United Kingdom.

{ddagger} Present address: Eden Project, Bodelva, Cornwall PL24 2SG, United Kingdom.

§ Present address: Risk Initiative & Statistical Consultancy Unit, Department of Statistics, University of Warwick, Coventry CV4 7AL, United Kingdom.


Applied and Environmental Microbiology, October 2006, p. 6452-6460, Vol. 72, No. 10
0099-2240/06/$08.00+0     doi:10.1128/AEM.00313-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Hamberger, A., Horn, M. A., Dumont, M. G., Murrell, J. C., Drake, H. L. (2008). Anaerobic Consumers of Monosaccharides in a Moderately Acidic Fen. Appl. Environ. Microbiol. 74: 3112-3120 [Abstract] [Full Text]