Abstract:
Laetiporus sulphureus is a globally distributed polypore fungus valued for its culinary, medicinal, and biotechnological applications. Despite its economic potential, this species remains notably under-domesticated, and almost no cultivation protocols exist for tropical regions. In northern Thailand, L. sulphureus is rare and seasonal, and is harvested exclusively from the wild, highlighting the need for reliable cultivation methods. This study provides the first systematic assessment of substrate suitability for Thai strains of L. sulphureus using both hardwood logs (mango, para rubber, and castanopsis) and para-rubber sawdust across 12 substrate formulations. Two strains (MFLUCC 12-0546 and MFLUCC 12-0547) were successfully propagated on sorghum grains, producing high-quality spawn. Log cultivation resulted in limited and transient colonization in Castanopsis, with no fruiting after six months. In contrast, sawdust-bag cultivation revealed clear substrate-dependent performance: formulas F11 and F12 supported rapid and complete colonization and induced primordia formation, whereas nutrient-poor formulas (F1–F5) failed to support growth. Although mature fruiting bodies were not obtained, this study identifies the first substrate formulations capable of initiating reproductive development, including primordia formation, in Thai L. sulphureus strains and it provides quantitative baseline data on colonization behavior under tropical conditions. These findings highlight the species’ sensitivity to substrate composition, nutrient balance, and environmental triggers such as temperature and humidity. The study establishes foundational parameters for future optimization and represents a critical step toward domestication of L. sulphureus in Southeast Asia, with potential long-term benefits for local mushroom production and commercial diversification.
