We analyzed an isolate of fungus that seems to be a new type orchid mycorrhizal fungus, “KMI (refers to Kyoto-Ma- tsubara-Ishii)”, obtained from the roots of Paphiopedilum thailandense Fowl. KMI has hyphal branching...We analyzed an isolate of fungus that seems to be a new type orchid mycorrhizal fungus, “KMI (refers to Kyoto-Ma- tsubara-Ishii)”, obtained from the roots of Paphiopedilum thailandense Fowl. KMI has hyphal branching into right angle similar to Rhizoctonia-like fungi, but its spore formation resembled Nectoria, which is known as a teleomorph of Fusarium rather than Rhizoctonia. Its ribosomal DNA sequences of 18S and ITS have no similarity with any known fungal species. Proteins in molecular weight of 53 and 24 kDa, which are common to mycorrhizal fungi, were detected in KMI. When KMI was inoculated onto orchids, however it didn’t form pelotons or coils, but the hyphae in the root tissues were observed and the tissues were not decayed. No significant symptoms of Rhizoctonia or Fusarium disease, however, were developed on tomato and cucumber plants. The evidences suggest that KMI is a new type of orchid mycorrhizal fungus.展开更多
文摘We analyzed an isolate of fungus that seems to be a new type orchid mycorrhizal fungus, “KMI (refers to Kyoto-Ma- tsubara-Ishii)”, obtained from the roots of Paphiopedilum thailandense Fowl. KMI has hyphal branching into right angle similar to Rhizoctonia-like fungi, but its spore formation resembled Nectoria, which is known as a teleomorph of Fusarium rather than Rhizoctonia. Its ribosomal DNA sequences of 18S and ITS have no similarity with any known fungal species. Proteins in molecular weight of 53 and 24 kDa, which are common to mycorrhizal fungi, were detected in KMI. When KMI was inoculated onto orchids, however it didn’t form pelotons or coils, but the hyphae in the root tissues were observed and the tissues were not decayed. No significant symptoms of Rhizoctonia or Fusarium disease, however, were developed on tomato and cucumber plants. The evidences suggest that KMI is a new type of orchid mycorrhizal fungus.
