Soft rot disease caused by Klebsiella aerogenes on Austrocylindropuntia subulata in Iran

During the surveys in the major cactus-growing regions of Mazandaran Province of Iran, symptoms of soft rot were observed on the Eve's pin (Austrocylindropuntia subulate) plants. Cactus samples with typical symptoms including soft rot, black colored and water-soaked lesion at the entire of plants stem were collected and transferred to the laboratory for further assays. Isolation of causal agent from the infected stems and phenotypical and biochemical tests were performed using conventional microbiological methods. Based on isolates reactions in phenotypic tests, the isolates were found to belong to Enterobacteriaceae. The characteristics of the representative isolate were determined by amplification and sequencing of rpoB gene. In conclusion, the causal pathogen from the affected cactus was identified as Klebsiella aerogenes based on its pathogenicity, physiological and biochemical properties and molecular test. This is the first attempt to confirm the occurrence of soft rot disease of A. subulata caused by K. aerogenes in Iran.