Brenneria salicis

Brenneria salicis
Scientific classification
Kingdom: Bacteria
Phylum: Proteobacteria
Class: Gamma Proteobacteria
Order: Enterobacteriales
Family: Enterobacteriaceae
Genus: Brenneria
Binomial name
Brenneria salicis
(Day 1924)
Hauben et al. 1999
Synonyms

Bacterium salicis Day 1924
Phytomonas salicis (Day 1924) Magrou 1937
Pseudobacterium salicis (Day 1924) Krasil’nikov 1949
Erwinia amylovora var. salicis Martinec and Kocur 1963
Pseudomonas saliciperda Lindeijer 1932
Erwinia salicis (Day 1924) Chester 1939

Brenneria salicis is a Gram-negative bacterium that is pathogenic on plants.

The bacterium is known to cause 'watermark disease' in willow (Salix ssp.) trees. Watermark disease affects infected trees by occluding the xylem vessels, impeding circulation. Early signs of the disease are wilting or dried-out, dead leaves on intermittent branches throughout the tree's crown. Cross sections from affected branches show a watery, transparent discoloration to an orange-brown staining in the wood. Cross sections of a killed tree's main stem are blanched completely white.[1][2]

The white willow, S. alba, is very sensitive to watermark disease, while the crack willow, S. fragilis, is considerably less so. Hybrids of these two species have shown intermediate sensitivity.[2]

References

  1. PCR-Based Detection of the Causal Agent of Watermark Disease in Willows, authors: L. Hauben, M. Steenackers, and J. Swings; Applied and Environmental Microbiology, October 1998, p.3966-3971, Vol.64, No.10
  2. 2.0 2.1 Willow Resistance to the Watermark Disease, author: M. Steenackers. http://www.inbo.be/content/page.asp?pid=EN_SUS_FOR_FRM_IMP_willows_path

Further reading

Maes, M; Baeyen, S; De Croo, H; De Smet, K; Steenackers, M (2002). "Monitoring of endophytic Brenneria salicis in willow and its relation to watermark disease.". Plant Protection Science 38 (Special Issue 2): 528.