Pathogens on plants

In some cases pectinolytic enzymes have been associated with virulence and it is generally accepted that pectinolysis by these bacteria facilitates their entry and spread in plant tissue. In Rhizohium, these enzymes may play a role in the root infection process that precedes nodule formation (Hubbell et al 1978). A. irakense has never been reported to be pathogenic on plants. It can therefore be speculated that moderate and strictly regulated pectinolysis of A. irakense facilitates entry in the outer cortex of plants roots, since A. irakense has been isolated from surface-sterilized roots. It is likely that breakdown of plant polysaccharides by root colonizing bacteria can provide them with extra carbon source. 

Brandi, M. T. (2006). Fitness of human enteric pathogens on plants and implications for food safety (1). Annu. Rev. Phytopathol. 44,367-392. 

Burdon, J.J. The effect of fungal pathogens on plant communities. In The Plant Community as a Working Mechanism. Newman E.I. ed., Oxford, UK Blackwell Scientific Publications, 1982. 

KENERLEY ANDREWS Itittnctioluef Pathogens on Plant Luff Surfaces 199... 

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