Identification of Strawberry Root Rot Pathogeny Caused by Fusarium in Beijing

A high incidence of strawberry root rot was observed in Changping District of Beijing in April 2011 and 35 samples of affected plants were collected at random.Thirteen strains were taken at the colony edge for subculture and purification.The purified isolates were primarily identified based on morphological and colony characteristics.It was found that all strains isolates were similar in morphology and colony.Analysis of rDNA-ITS sequence of isolates indicated that the strains were Fusarium oxysporum.The healthy strawberries were used for fungal pathogenicity test.All isolates had pathogenicity.Symptoms became to appear 2 weeks after inoculation.The pathogens were recovered from strawberry roots,confirming Koch's postulates.Based on the morphological characteristics,pathogenicity test and molecular methods,strawberry root rot pathogens were identified as Fusarium oxysporum.