Identification of Pathogens Causing Flue-cured Tobacco Brown Spot in Hubei Province

In order to study the species and geographical distribution of tobacco brown spot disease in tobacco fields of Hubei Province, seventy two isolates causing tobacco brown spot in Hubei Province were identified based on morphology and eight typical isolates were analyzed based on sequences of rDNA-ITS and ATPase. The results showed that the pathogens causing tobacco brown spot in Hubei tobacco areas were identified as Alternaria alternata, A. longipes, A. tenuissima and A. yaliinficiens. Among them, A. longipesis was the dominant species distributed in all tobacco-growing areas in Hubei with a high occurrence of 69%. A. tenuissima and A.alternata were found in three areas of Yichang, Shiyan and Enshi. A. yaliinficiens was only isolated in Enshi. In addition, the results also indicated that ATPase gene sequence comparison could be a useful way to differentiate the four pathogensof tobacco brown spot.