Predominance of Nonculturable Cells of the Biocontrol Strain Pseudomonas fluorescens CHA0 in the Surface Horizon of Large Outdoor Lysimeters.

Details

Serval ID
serval:BIB_2CDAA1601419
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Predominance of Nonculturable Cells of the Biocontrol Strain Pseudomonas fluorescens CHA0 in the Surface Horizon of Large Outdoor Lysimeters.
Journal
Applied and Environmental Microbiology
Author(s)
Troxler J., Zala M., Moenne-Loccoz Y., Keel C., Defago G.
ISSN
0099-2240 (Print)
ISSN-L
0099-2240
Publication state
Published
Issued date
1997
Volume
63
Number
10
Pages
3776-3782
Language
english
Abstract
The persistence of the biocontrol agent Pseudomonas fluorescens CHA0 in the surface horizon of 12 large outdoor lysimeters planted with winter wheat, Phacelia tanacetifolia followed by spring wheat, or maize was monitored for 1 year. Soil was inoculated with a spontaneous rifampin-resistant mutant (CHA0-Rif) of CHA0, and the strain was studied by using colony counts, Kogure's direct viable counts, and total counts (immunofluorescence). The number of culturable cells of the inoculant decreased progressively from 8 to 2 log CFU/g of soil or lower. However, culturable cells of CHA0-Rif accounted for less than 1% of the total cells of the inoculant 8 months after release in autumn. Since viable but nonculturable cells represented less than a quarter of the latter, most cells of CHA0-Rif in soil were thus inactive-dormant or dead at that time. Nonculturable cells of the inoculant were predominant also in the surface horizon of the lysimeters inoculated in the spring, and a significant fraction of them were viable. Results suggest that the occurrence of nonculturable cells of CHA0-Rif was influenced by climatic factors (water availability and soil temperature) and the abundance of roots in soil. The fact that the inoculant persisted as mixed populations of cells of different physiological states, in which nonculturable cells were predominant, needs to be taken into account when assessing the autecology of wild-type or genetically modified pseudomonads released into the soil ecosystem.
Pubmed
Web of science
Create date
24/01/2008 14:51
Last modification date
20/08/2019 14:11
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