بيماري لكه قهوه اي قارچ خوراكي در ايران

Brown blotch of cultivated mushroom (Agaricus bisPorus) has become a major and widespread disease of the crop in mushroom growing facilities throughout Iran. Disease symptoms, as brown, sunken lesions and blotches appear on pilei and stipes in all stages of mushroom growth, during shipment and in the retail market. In severely affected mushrooms and under favourable conditions, the lesions enlarge coalesce and encompass the entire surface of the caps. The rotted mushrooms assume a slimy appearance. A fluoroscent oxidase and arginine dihyolrdase positive pseudomonad was isolated from the diseased mushrooms. The identity of the strains as Pseudomonas tolaasii was verified through phenotypic characterization, proof of pathogenicity and the white-line reaction with Pseudomonas `reactanceʹ. The strains differed in virulence and were placed in four virulence groups.