Identification of pathogen causing corynespora leaf spot of tobacco in Jiangxi

In order to identify the pathogen of flue－cured tobacco corynespora leaf spot disease in Ji’an，Jiangxi Province，the fungi was isolated from diseased tobacco leaves. Based on the pathogenicity，morphological characteristics and the sequence of ribosomal DNA －ITS，the pathogen was identified as Corynespora cassiicola，and the homology analysis showed the sequence of ribosomal DNA －ITS isolated from the strains had homology of more than 99% with Corynespora cassiicola published in GenBank. Finally，the pathogen was indicated as Corynespora cassiicola（Berk. ＆ Curt.）Wei. The results of biological characteristics showed that fungus couldn’t survive below 9℃ or above 39℃，grew best at 26.5℃. It produced the most spores at 29℃，and the conidia germination was the most at 26.5℃. The disease is the first report in Jiangxi，China.