Molecular Plant-Microbe Interactions (2000) 13, 1340-1345

T.F.C. Chin-A-Woeng, G.V. Bloemberg, I.H.M. Mulders, L.C. Dekkers and B.J.J. Lugtenberg (2000)
Root colonization by phenazine-1-carboxamide-producing bacterium Pseudomonas chlororaphis PCL1391 is essential for biocontrol of tomato foot and root rot
Molecular Plant-Microbe Interactions 13 (12), 1340-1345
Abstract: The phenazine-1-carboxamide-producing bacterium Pseudomonas chlororaphis PCL1391 controls tomato foot and root rot caused by Fusarium oxysporum f. sp. radicis-lycopersici. To test whether root colonization is required for biocontrol, mutants impaired in the known colonization traits motility, prototrophy for amino acids, or production of the site-specific recombinase, Sss/XerC were tested for their root tip colonization and biocontrol abilities. Upon tomato seedling inoculation, colonization mutants of strain PCL1391 were impaired in root tip colonization in a gnotobiotic sand system and in potting soil. In addition, all mutants were impaired in their ability to control tomato foot and root rot, despite the fact that they produce wild-type levels of phenazine-1-carboxamide, the antifungal metabolite previously shown to be required for biocontrol. These results show, for what we believe to be the first time, that root colonization plays a crucial role in biocontrol, presumably by providing a delivery system for antifungal metabolites. The ability to colonize and produce phenazine-1-carboxamide is essential for control of F. oxysporum f. sp. radicis-lycopersici. Furthermore, there is a notable overlap of traits identified as being important for colonization of the rhizosphere and animal tissues.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Ben J.J. Lugtenberg

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Fusarium crown and root rot	Tomato (Solanum lycopersicum)
Pseudomonas chlororaphis (antagonist)	Fusarium crown and root rot	Tomato (Solanum lycopersicum)
	Fusarium oxysporum