Xylella fastidiosa

Taxobox
color = lightgrey
name = "Xylella fastidiosa"
regnum = Bacteria
phylum = Proteobacteria
classis = Gamma Proteobacteria
ordo = Xanthomonadales
familia = Xanthomonadaceae
genus = "Xylella"
species = "X. fastidiosa"
binomial = "Xylella fastidiosa"
binomial_authority = Wells et al., 1987

"Xylella fastidiosa" (also known as Pierce's disease) is a Gamma Proteobacteria that is an important plant pathogen, causing several plant diseases including phoney peach disease in the southern United States, oleander leaf scorch and Pierce's disease in California and Texas, and citrus X disease in Brazil.

Pierce's disease

Pierce's disease is a disease affecting grapes, able to quickly kill vineyards. There is no known cure.winepros.com.au. Cite web|last= "Oxford Companion to Wine"| title= Pierce's disease |url= http://www.winepros.com.au/jsp/cda/reference/oxford_entry.jsp?entry_id=2428 ] Pierce's disease has long been a scourge to California's vintners. Between its discovery in 1892 near Anaheim and 1906, the disease had destroyed 39,500 acres (16,000 ha) of vines. With the introduction of the glassy-winged sharpshooter from the southeastern U.S., however, the spread of Pierce's disease has increased dramatically.

There are no resistant "Vitis vinifera" varieties, and Chardonnay and Pinot Noir are especially sensitive, although muscadine grapes have a natural resistance. Pierce's disease is presently found in the south eastern United States, Mexico, Costa Rica, and Venezuela and possibly other parts of Central and South America. There are isolated hot spots of the disease near creeks in Napa and Sonoma in northern California.

When a vine becomes infected, the bacterium causes a gel to form in the xylem tissue of the vine, preventing water from being drawn through the vine. Leaves on vines with Pierce's disease will turn yellow and brown and eventually drop off the vine. Shoots will also die. After 1 to 5 years, the vine itself will die. The proximity of vineyards to citrus orchards compounds the threat because citrus is not only a host for the sharpshooter eggs, but it is also a popular overwintering site for the insect. Likewise, oleander is a common landscaping plant in California, and it also serves as a reservoir for "Xylella".

Oleander leaf scorch

Oleander leaf scorch is a disease of landscape oleanders ("Oleander nerium") caused by a strain of "X. fastidiosa" and has become prevalent in California and Arizona, USA. The disease is transmitted by another sharpshooter ("Homalodisca liturata"), a leafhopper.

Genome sequencing

The genome sequencing of "X. fastidiosa" was realized by a pool of over 30 research labs in the State of São Paulo, Brazil, and funded by this State's Science Foundation (FAPESP). cite journal |last= |first= |authorlink= |coauthors= |year=2008 |month=Jun |title= |journal=Nature Reviews Genetics |volume=9 |issue= |pages=487 - 493 |id= |url= |accessdate=2008-07-18 |quote=

References

*APHIS. 2002. [http://www.aphis.usda.gov/lpa/pubs/fsheet_faq_notice/fs_phglassy.html Glassy-winged Sharpshooter and Pierce's Disease in California]
*Univ. of Arizona. 2006 [http://cals.arizona.edu/PLP/plpext/diseases/trees/oleander/oleleaf.htm Oleander leaf scorch]
*cite journal |author=Wells, J. M., B. C. Raju, H. Y. Hung, W. G. Weisburg, L. M. Parl and D. Beemer |year=1987 |title="Xylella fastidiosa" gen. nov., sp. nov.: Gram-negative, xylem-limited, fastidious plant bacteria related to "Xanthomonas" spp. |journal=International Journal of Systematic Bacteriology |volume=37 |pages=136–143;Footnotes