Publications des scientifiques de l'IRD

Mensi I., Vernerey M. S., Gargani D., Nicole Michel, Rott P. (2014). Breaking dogmas : the plant vascular pathogen Xanthomonas albilineans is able to invade non-vascular tissues despite its reduced genome. Open Biology, 4, art. 130116 [13 p.]. ISSN 2046-2441.

Titre du document
Breaking dogmas : the plant vascular pathogen Xanthomonas albilineans is able to invade non-vascular tissues despite its reduced genome
Année de publication
2014
Type de document
Article référencé dans le Web of Science WOS:000332388000002
Auteurs
Mensi I., Vernerey M. S., Gargani D., Nicole Michel, Rott P.
Source
Open Biology, 2014, 4, art. 130116 [13 p.] ISSN 2046-2441
Xanthomonas albilineans, the causal agent of sugarcane leaf scald, is missing the Hrp type III secretion system that is used by many Gram-negative bacteria to colonize their host. Until now, this pathogen was considered as strictly limited to the xylem of sugarcane. We used confocal laser scanning microscopy, immunocytochemistry and transmission electron microscopy (TEM) to investigate the localization of X. albilineans in diseased sugarcane. Sugarcane plants were inoculated with strains of the pathogen labelled with a green fluorescent protein. Confocal microscopy observations of symptomatic leaves confirmed the presence of the pathogen in the protoxylem and metaxylem; however, X. albilineans was also observed in phloem, parenchyma and bulliform cells of the infected leaves. Similarly, vascular bundles of infected sugarcane stalks were invaded by X. albilineans. Surprisingly, the pathogen was also observed in apparently intact storage cells of the stalk and in intercellular spaces between these cells. Most of these observations made by confocal microscopy were confirmed by TEM. The pathogen exits the xylem following cell wall and middle lamellae degradation, thus creating openings to reach parenchyma cells. This is the first description of a plant pathogenic vascular bacterium invading apparently intact non-vascular plant tissues and multiplying in parenchyma cells.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020] ; Sciences du monde végétal [076]
Localisation
Fonds IRD [F B010061830]
Identifiant IRD
fdi:010061830
Contact