Pseudomonas corrugata: plant pathogen and/or biological resource?

SUMMARY Pseudomonas corrugata is the causal agent of tomato pith necrosis yet it is also used in the biological control of plant pathogenic bacteria and fungi. Potentially it could be used in other fields, such as the production of commercial biomolecules with a wide range of application and including bioremediation. This review reports the multiple characteristics of the bacterium, highlights its known molecular features and speculates on the possible underlying mechanisms of action. Taxonomy: Bacteria; Proteobacteria; γ subdivision; order Pseudomonadales; family Pseudomonadaceae; genus Pseudomonas. Microbiological properties: Gram-negative, oxidase-positive, non-spore forming rods; non-fluorescent on King's B medium; produces wrinkled and rarely smooth colonies on yeast peptone glucose agar or nutrient dextrose agar; yellow to brown diffusible pigments are frequently produced. Disease symptoms: The typical symptom on tomato is necrosis and/or hollowing of the pith of the stem; the syndrome determines loss of turgidity of the plant, hydropic/necrotic areas and long conspicuous adventitious roots on the stem. Biological control agent:In vitro assessed against plant pathogenic fungi and bacteria, as well as the phytotoxin indicator microorganims Rhodotorula pilimanae and Bacillus megaterium; in vivo used against pre- and post-harvest plant pathogens.