关键词: 北苍术, 木贼镰刀菌, 病原菌鉴定, 生物学特性

Abstract: In recent years, with the expansion of the cultivation area of Atractylodes chinensis, the disease damage caused by pathogen has become more and more severe. To investigate the pathogen causing shoot blight of Atractylodes chinensis and its biological characteristics, the pathogen was identified based on the Koch’s postulates, morphological characteristics, molecular biological technology, and the optimum growth rate of mycelium were determined. The results showed that the aerial hyphae was villous to cotton-like, white to pink initially and turned camel color later, with sickle and curved conidia, significantly enlarged central cells, tapered apical spores, mostly had 3~7 compartmentals, spherical chlamydospores, chainlike or monogenic hyphae or spore. The pathogen ITS sequence shared 100% identity with that of Fusarium equiseti in GenBank (MK621018), and the pathogen was confirmed as Fusarium equiseti (GenBank accession No. MH290363). The optimum temperature for mycelial growth was 25~30 ℃, the mycelial  grew at pH 4~11, and the optimum pH  was 8~11. Oat and corn flour culture medium were the most suitable for mycelial growth; light conditions had great influence on the mycelium growth, and full light accelerated mycelial growth. The highest utilization rate of carbon-source starch, glucose and nitrogen-sourced yeast leaching powder was highest, and the diameter of the colony was about 7 cm when cultured for 7 d. The utilization rate of starch, glucose and yeast extract powder was the highest, and the diameter of the colony was about 7 cm when cultured 7 d.

Key words: Atracylodes chinensis, Fusarium equiseti, pathogen identification, biological characteristics