| A severe soybean disease occurred in in Shanghai recent years. The present study was conducted to identify the pathogen and survey the disease epidemiology in the soybean planting areas so as to make the disease control stratage in Shanghai. It was diagnosed as a bacterial disease based on the symptoms and microscopic observation. Twenty bacterial strains were isolated from the disease infected plants and seeds of soybean. They were tested by morphology, cultural characteristic, physiological and biochemical, pathogenicity, Biolog and fatty acid analysis and compared with those of 12 international standard reference strains. It has been confirmed that Pseudomonas savastanoi pv. glycinea is a causal organism of the bacterial blight of soybean in shanghai.The bacterium is seedborne and seed transmitted. The average percentage of seedborne and seed transmission of the 10 diseased seed samples was 7.6% and 1.2%, respectively.During 2002-2004 a field survey was conducted for epidemiology of the bacterial blight of soybean in 397.68 ha of soybeans in 7 regions of Shanghai. The disease appeared in all of the regions and varity Chunlv.shenxian, Liaoxian and 95-1 were infected. The average of the disease infection of soybean paints is 95% with over 50% of the leaf infection. It was found that the disease usually started in the end of April or beginning of May and reached the maximum infection stage in middle May to July. The disease severity varied with years and varieties. The disease was more severe in 2002 when there was longer duration of rainy season with high frequency of storms than in 2004 when it was shorter rainy season with lower moisture. The control strategies for bacterial blight of soybean were worked out based on the pathogen identification and the disease survey in Shanghai. It included plant quarantine, sanitation, eradication of diseased residues, using resistant varieties as well as chemical control in which some selected bacterial pesticides were used.
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