Growth and cultural-morphological characteristics of vegetative mycelia of medicinal caterpillar fungus ophiocordyceps sinensis G.H. Sung et al. (Ascomycetes) isolates from tibetan plateau (P.R. China)

The morphological and cultural characteristics of vegetative mycelia of 29 Tibetan strains of medicinal caterpillar fungus Ophiocordyceps sinensis (= Cordyceps sinensis) were studied. Data on mycelial growth of the above-mentioned fungi strains on different types of nutrients, the macro- and micromorphological description of colonies grown on different agar media, and anamorph stage identification are provided. It was shown that strains of O. sinensis demonstrated moderately slow growth on selected nutrients compared with other ascomycetous fungi. The highest growth rate value from all analyzed strains is O. sinenis N14-2.7 mm/day was completed with a mycelial run on potato-dextrose agar (pH = 6.0) in 15 d. Most of the examined strains preferred Sabouraun's dextrose agar; some of the strains preferred potato-dextrose agar as the medium for optimal development. The least favorable nutrient for all strains was Czapek solution agar. Analyses of morphological and microstructural peculiarities on different types of nutrients were conducted and detailed descriptions and illustrations were provided. Based on macro- and micromorphological characteristics, the investigated strains were identified as Hirsutella sinensis and Tolypocladium sinensis species, which were identified as the anamorphs of Ophiocordyceps sinensis.