Article

Genotypic and phenotypic variation among Lysobacter capsici strains isolated from Rhizoctonia suppressive soils.

Plant Research International, P.O. Box 69, 6700 AB Wageningen, The Netherlands. <>
Systematic and Applied Microbiology (impact factor: 3.37). 06/2010; 33(4):232-5. DOI:10.1016/j.syapm.2010.03.002 pp.232-5
Source: PubMed

ABSTRACT Four Gram-negative bacterial strains, recovered from clay soils cultivated with different crops in the Netherland, were subjected to a polyphasic taxonomic study in order to clarify their taxonomic status. Comparative analysis of the 16S rRNA gene sequences revealed that they belong to the genus Lysobacter and to be highly related to the type strains of L. antibioticus DSM 2044(T), L. gummosus DSM 6980(T), and L. capsici DSM 19286(T), displaying 99.1-99.3%, 99.2-99.6% and 99.4-100% sequence similarities, respectively, to these species. The results of DNA-DNA hybridization studies unambigiously indicated that the four strains belonged to the species L. capsici. Nevertheless, DNA fingerprinting and phenotypic characterization indicated that there was a considerable diversification and niche differentiation among the strains belonging to L. capsici. The newly identified L. capsici strains strongly inhibit Rhizoctonia solani AG2 and originate from Rhizoctonia-suppressive soils where also populations of L. antibioticus and L. gummosus were present. This is the first report of the presence of combined populations of closely related Lysobacter spp. within agricultural soils.

0 0
 · 
0 Bookmarks
 · 
33 Views
  • Source
    Article: Indigenous populations of three closely related Lysobacter spp. in agricultural soils using real-time PCR.
    Joeke Postma, Mirjam T Schilder, Richard A van Hoof
    [show abstract] [hide abstract]
    ABSTRACT: Previous research had shown that three closely related species of Lysobacter, i.e., Lysobacter antibioticus, Lysobacter capsici, and Lysobacter gummosus, were present in different Rhizoctonia-suppressive soils. However, the population dynamics of these three Lysobacter spp. in different habitats remains unknown. Therefore, a specific primer-probe combination was designed for the combined quantification of these three Lysobacter spp. using TaqMan. Strains of the three target species were efficiently detected with TaqMan, whereas related non-target strains of Lysobacter enzymogenes and Xanthomonas campestris were not or only weakly amplified. Indigenous Lysobacter populations were analyzed in soils of 10 organic farms in the Netherlands during three subsequent years with TaqMan. These soils differed in soil characteristics and crop rotation. Additionally, Lysobacter populations in rhizosphere and bulk soil of different crops on one of these farms were studied. In acid sandy soils low Lysobacter populations were present, whereas pH neutral clay soils contained high populations (respectively, <4.0-5.87 and 6.22-6.95 log gene copy numbers g(-1) soil). Clay content, pH and C/N ratio, but not organic matter content in soil, correlated with higher Lysobacter populations. Unexpectedly, different crops did not significantly influence population size of the three Lysobacter spp. and their populations were barely higher in rhizosphere than in bulk soil.
    Microbial Ecology 03/2011; 62(4):948-58. · 2.91 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

16S rRNA gene sequences
 
agricultural soils
 
clay soils
 
different crops
 
DNA fingerprinting
 
DNA-DNA hybridization studies unambigiously
 
first report
 
genus Lysobacter
 
identified L. capsici strains
 
L. antibioticus
 
L. capsici
 
L. gummosus
 
Lysobacter spp
 
niche differentiation
 
polyphasic taxonomic study
 
populations
 
Rhizoctonia solani AG2
 
Rhizoctonia-suppressive soils
 
species L. capsici
 
taxonomic status
 

J. Postma