Fungal Isolate “KMI” Is a New Type of Orchid Mycorrhizal Fungus

Tomoko Matsubara, Motohito Yoneda, Takaaki Ishii

Graduate School of Life Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan..

DOI: 10.4236/ajps.2012.38135                

Abstract

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.

Keywords

KMI; Orchid Mycorrhizal Fungus; Paphiopedilum thailandense; Protein Analysis, Ribosomal DNA Sequence

Conflicts of Interest

The authors declare no conflicts of interest.

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