Thesis (M.Sc.) - Cairo University - Faculty of Agriculture - Department of Plant Pathology and Physiology

The aim of this study is to isolation and identification Erwinia carotovora bacteria as causal agent of soft rot disease in some vegetables. Samples were collected from the storage and marketing places in Giza and Beni Suef governorates. Four isolates (potato tubers); one isolate (sweet potato); three isolates (cucumber); three isolates (carrot); two isolates (eggplant); one isolate (red sweet pepper) ; two isolates (chili) and one isolate (tomato) were isolated, from naturally infected plant samples according to standard bacteriological methods, on nutrient glucose (2%) agar medium. These bacterial isolates were showed a variation in their pathogenicty on host range or their ability for fermentation of tested sugars. According to cultural, physiological and biochemical characters 15 bacterial isolates were defined as E. carotovora subsp. carotovora, while two isolates as Erwinia. chrysanthemi. The protein fingerprint of isolates differed in their number of discrete protein bands, their molecular weight and the similarity between them. The tree dendrogram showed that bacterial isolates can be divided into two main groups. In vitro tests, bio-agents, aqueous plant extracts and chemicals, using filter paper disc plate method in Petri dish, had different antagonistic effects against bacterial soft rot isolates

Issued also as CD