Nutritional and physical requirements for mycelial growth and fruiting body production of six strains of Pleurotus djamor from Luzon Island, Philippines

Pleurotus djamor, a wood-rotting basidiomycetous mushroom, is becoming popular in the Philippines due to its attractive and fascinating color. With our intention to properly harness the maximum values of wild strains of P. djamor for various applications, our team investigated the mycelial growth and fruiting body performance of six strains of P. djamor collected from the different regions of Luzon Island, Philippines. Pure cultures of mushroom mycelia were successfully established and the nutritional and physical requirements for mycelial growth were determined. Fructification ability, yield and biological efficiency of the six strains were comparatively evaluated. Mycelia of TLPD 1, 2 and 3 favorably grew on potato sucrose gulaman (PSG), whereas TLPD 4, 5 and 6 luxuriantly grew on mycological agar (MA). Corn grit decoction gulaman (CGDG) and malt extract agar (MEA) were also favorable for TLPD 1, 3 and 5, respectively. The optimal pH for mycelial growth of TLPD 1, 4 and 6 was found at pH 7.0 – 8.0 whereas TLPD 2, 3 and 5 grew at a wide range of pH. All strains positively respond to both aeration conditions and both illumination conditions, except TLPD 5, which significantly recorded higher growth rates in sealed and dark conditions. Moreover, mycelia of all strains grew better when incubated at room temperature (30oC) and air-conditioned (23oC), while no growth was noted at refrigerated condition. In fruiting body cultivation, TLPD 1 strain displayed the shortest incubation period (12 days) and primordial initiation (14.2 days), while TLPD 4 registered the longest period of cultivation phases. TLPD 3 significantly produced the highest yield of 125.34 g bag-1 and biological efficiency of 25.07%, followed by TLPD 4 and 2. No significant difference was found among strains in terms of cap diameter and stipe length. Therefore, individual strain of P. djamor has unique character and specific nutritional and physical preference, which is necessary to understand for strain selection.