Identification and Biological Characteristics of Stem Rot Pathogen of Dendrobium officinale

  Objective   To isolate and identify and determine the biological characteristics of the pathogen that caused the stem rot disease on Dendrobium officinale.

  Method  Typical diseased plants were collected from 3 farms in Zhaoan and Songxi for pathogen isolation. Morphological and molecular identification methods including gene sequencing of ITS, EF1-α, ACT, RPB2, and LSU were performed on the isolates. Biological characteristics of the pathogen in response to temperature, pH, light condition, carbon source, and nitrogen source were determined.

  Result  The pathogen was identified as Fusarium oxysporum, which grew optimally at 30 ℃ and pH 7 under light on a medium using starch for carbon and peptone for nitrogen sources.

  Conclusion   F. oxysporum was identified to be the pathogen that caused the stem rot disease on D. officinale in Fujian, and the optimal mycelial growth conditions determined.