Rhizoplane colonisation of peas by Rhizobium leguminosarum bv. viceae and a deleterious Pseudomonas putida.
Pseudomonas putida strain A313, a deleterious rhizosphere bacterium, reduced pea nitrogen content when inoculated alone or in combination with Rhizobium leguminosarum bv. viceae on plants in the presence of soil under greenhouse conditions. When plants were grown gnotobiotically in liquid media, mixed inocula of A313 and rhizobia gave a higher proportion of small evenly distributed nodules when compared with a single rhizobial inoculation. In addition, the rhizobial root establishment was reduced by A313 irrespective of inoculum density, indicating that A313 has the capacity to interact with the early rhizobial infection process. When pea seedlings were simultaneously inoculated with A313 and rhizobia, A313 colonised the root hairs to the same extent as the rhizobia, according to analysis by immunofluorescence microscopy. This suggests that the root hair colonisation trait of P. putida interferes with the onset of the symbiotic process.
Berggren
Ingela
I
Department of Soil Sciences, P.O. Box 7014, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden.
Alström
Sadhna
S
van Vuurde
J W L
JW
Mårtensson
Anna M
AM
D000704:Analysis of Variance; D008856:Microscopy, Fluorescence; D009584:Nitrogen / Q000378:metabolism; D018532:Pisum sativum / Q000378:metabolism / Q000382:microbiology*; D018517:Plant Roots / Q000382:microbiology*; D016958:Pseudomonas putida / Q000472:pathogenicity / Q000502:physiology*; D016961:Rhizobium leguminosarum / Q000502:physiology*; D013559:Symbiosis
D009584:Nitrogen