Is Pseudomonas syringae a friend or a foe???

 

  • Pseudomonas syringae is a plant pathogen. This pathogen exhibits it’s pathogenic traits by the characteristic of biological ice nucleation. In the presence of the ICE(+) gene P. syringae causes frost damage on outer plant tissues which allows the nutrients of tissues below to become http://en.wikipedia.org/wiki/Image:Barley.jpgavailable for the metabolic processes of P. syringae. This successful nutrient acquisition then allows for the growth of P. syringae, i.e. the duplication of cells per binary fission.

 

 

  • Strains of P. syringae are known to infect a wide range of plant species such as maple trees, cherry trees, beets, peas, crabapples, species of grass, barley, tomatoes, wheat, lilac trees, and wild beans. P. syringae causes damage to http://en.wikipedia.org/wiki/Image:Beets_produce-1.jpgthe plant hosts in a number of ways. Currently, research is being done on P. syringae as the cause of bacterial cankers on Prunus avium L., otherwise known as sweet cherries. To view more on this specific project please see http://www2.warwick.ac.uk/fac/sci/whri/about/staff/jvicente/bacterialcanker_of_cherry/ .
  • Because of P. syringae’s close association with plants, particularly a number of agriculturally produced plants, they are in turn quite closely associated with ushttp://upload.wikimedia.org/wikipedia/commons/thumb/c/c5/Foods.jpg/250px-Foods.jpg, that is human beings. As the world’s population is increases the survival of crops is incredibly important both economically and for survival.
  • Because of the devastating effects this organism can have on crops a number of methods for fighting this bacterium have been studied.  The most notable of these is the discovery and the exploitation of the mutant ICE (-) strains. This mutant has all of the same characteristics as the ICE (+) strain except those of ice nucleation. This means that, when introduced, this organism can populate the same area as the ICE (+) strains and compete for nutrients and space. For more information about this check out http://pmb.berkeley.edu/newPMB/faculty/lindow/lindow.shtml .

 

 

  • Another notable plant pathogen that is Eukaryotic and has also had a major impact both historically and economically is Phytophthora infestans. This http://en.wikipedia.org/wiki/Image:Symptom_potato_late_blight.jpgorganism is the cause of potato blight, the biological cause of the potato famine of the 1840’s. More information on this fungal plant pathogen is  viewable at http://bioweb.uwlax.edu/bio203/s2007/benrud%5Fjaco/ .