Comparison of physiological and cultivation characteristics of wild strains of Nameko (Pholiota microspora) from Bhutan and Japanese commercial spawn
Atsushi Kumata1,*, Rita Gurung2,3, Sabitra Pradhan2, Karma Thinley2, Dorji2, Chencho Dukpa2, Shingo Kaneko4
Affiliations
1Japan Overseas Cooperation Volunteer, National Mushroom Center, Wangchutaba, Babesa, Thimphu, Bhutan; 2National Mushroom Centre, Wangchutaba, Babesa, Thimphu, Bhutan; 3Murdoch University, 90 South St., Murdoch WA 6150, Australia; 4Faculty of Symbiotic Systems Science, Fukushima University, Fukushima 960-1296, Japan
*Correspondence: kumata.atsushi.kinoko@gmail.com
Abstract
Wild fruiting bodies of Pholiota microspora (Berk.) Sacc., commonly known as nameko, were collected from five locations in western Bhutan at altitudes ranging from 1,769 to 3,100 m between 2018–2022. Morphological and microscopic observations of the specimens submitted to the national herbarium revealed no clear basis for subspecies differentiation. To support the development of domestic cultivation and potential overseas marketing of nameko in Bhutan, eight Bhutanese wild strains isolated from these specimens were evaluated and statistically compared with two Japanese commercial strains. The aim was to assess their industrial applicability and gather key traits for breeding strategies. The Bhutanese wild strains exhibited notable diversity in cap and stem coloration as well as in mycelial growth characteristics. Unlike the Japanese strains, none of the Bhutanese strains exhibited the formation of abnormal dedikaryotized flat sectors under incubation at 25 °C and 30 °C, a phenomenon known to negatively impact cultivation stability. All Bhutanese strains displayed bipolar mating systems and were capable of mating with Japanese strains, suggesting strong potential as breeding material to address the genetic bottleneck caused by the reliance on a single ancestral strain in Japan’s air-conditioned nameko cultivation. All tested wild strains successfully formed fruiting bodies on sawdust substrate and tended to exhibit early fruiting. Two strains that showed yields comparable to Japanese strains and significantly earlier harvest times were selected as candidates for practical cultivation in Bhutan. These findings indicate that selective breeding from wild fruiting bodies represents a highly effective and accessible strategy for developing commercially viable nameko strains suited to Bhutanese agriculture and beyond.
Citation
Kumata, A., Gurung, R., Pradhan, S., Thinley, K., Dorji, D., Dukpa, C., & Kaneko, S. (2025). Comparison of physiological and cultivation characteristics wild strains of Nameko (Pholiota microspora) from Bhutan and Japanese commercial spawn. MycoAsia, 2025/04. https://doi.org/10.59265/mycoasia.2025-04
Submission History
Received: 08 August 2024
Accepted: 09 March 2025
Published: 03 June 2025
Editorial Team
Handling Editor: Dr. Belle Damodara Shenoy
Reviewers: Prof. Samantha C. Karunarathna, Dr. Avneet Pal Singh