Bui Thanh Thu * , Nguyen Dac Khoa and Tran Quoc Tuan

* Correspondence: Bui Thanh Thu (email: buithanhthu27@gmail.com)

Main Article Content


Shallot (Allium ascalonicum) is an important crop of Vinh Chau town, Soc Trang province of Vietnam. This study aims at identifying the contemporary pathogens in shallot fields in this region. The identification was done using the Koch’s postulates, morphological observation and molecular techniques. A collection of 124 infected shallot samples was obtained from three cropping seasons during 2015-2016 at three major shallot producing areas of Vinh Chau town. From these samples, a total of 49 bacterial and 118 fungal isolates were obtained. Using the Koch’s postulates, 160 isolates were confirmed to be shallot pathogens. Based on morphological observation and molecular techniques, i.e., PCR using specific primers and sequencing of the 16S rRNA genes, the pathogens were identified as Erwinia carotovora (soft rot), Pseudomonas aeruginosa (bulb rot), Aspergillus niger (black mold), Colletotrichum gloeosporioides (anthracnose) and Fusarium oxysporum (basal rot). Among these, E. carotovora and F. oxysporum appeared to be the predominant pathogens causing bulb rot in the shallot fields of Vinh Chau town.
Keywords: Aspergillus niger, Colletotrichum gloeosporioides, Erwinia carotovora, Fusarium oxysporum, Pseudomonas aeruginosa, shallot

Article Details


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