Plant pathogenic bacterial infections

The idea that exopolysaccharides (EPS) produced by several plant pathogenic bacteria could be involved in the pathogenic processes and or/the saprophytic or epiphytic phases of the life cycle appears to be generally accepted. Copious EPS production is often associated with increased virulence [89]. It is conceivable that the EPSs prevent bacterial elicitors of host-defence responses from reaching the plant and may inhibit deleterious adherence during infection, thus "maintaining (in both cases) a compatible interaction" [89],... 

For a majority of fungal and bacterial plant pathogens, infection occurs from water droplets or films of free moisture on the plant surface, or in an atmosphere of greater than 95% relative humidity. For many of these pathogens, primary and secondary dispersion occurs in rain splash or wind-blown rain, as well. 

Studies with simulated acidic rain found growth of the bacterial plant pathogen Pseudomonas phaseolicola totally inhibited by a solution of pH 3.2.When these solutions were used for inoculation of Phaseolus vulgaris Red Kidney test plants, no infection or disease development was observed. Control plants inoculated with solutions at pH 5.6 developed normal disease patterns. Additional studies with other host-parasite pairs are summarized in Table II. 

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