Screening and Identification of an Endophytic Fungus from Belamcanda chinensis Resistant to Wheat Pathogenic Fungi and Analysis of its Polyketone Synthase Gene

PurposeTo excavate useful endophytic fungi resources of Belamcanda chinensis and provide some reference for their rational utilization.

MethodsAn endophyte isolate Fusarium proliferatum SG5, was obtained from the roots of B. chinensis. The strain was identified by using internal transcribed spacer sequencing and morphological features, and the antifungal activities of fermentation broth of SG5 stain against two wheat pathogenic pathogens, including F. graminearum and Bipolaris sorokinianum Sacc.ex Sorok, were evaluated by the method of mycelial growth. The PKS sequence as well as some biological characteristics of the strain were also measured.

ResultThe SG5 strain was identified as F. proliferatum based on morphological characteristics and ITS sequence analysis. The fermtenation broth of SG5 strain had antagonistic activities against F. graminearum and B. sorokinianum. The amino acid sequence of PKS showed 99.7% identifies to the known F. proliferatum PKS gene sequence in the GenBank. The study on the biological characteristics exhibited that the proper growth agar of the strain was on Czape’s medium, and suitable carbon sources was sucrose while the optimal nitrogen source was potassium nitrate. The proper growth pH was 7. In addition, strain show tolerance to 1% NaCl.

ConclusionThis study indicates the SG5 strain is potential biocontrol resources of wheat pathogenic pathogens, and have certain value of development and application.