Invasive Grass Species <em>Megathyrsus maximus</em> and <em>Cenchrus setosus</em> for the Preparation of Substrate Media for Mushroom Cultivation in <em>Jun Cao</em> Technology; Alternatives to Sawdust Medium

Purpose: This study was conducted to prepare mushroom substrate media using Megathyrsus maximus and Cenchrus setosus, two invasive grass species in Sri Lanka by Jun Cao technology, with an anticipation of addressing the issue of shortage of sawdust to prepare substrate mixtures and as a strategy for controlling the grass populations simultaneously.Research Method: Commercial mushroom, Pleurotus floridanus, Pleurotus djamor, Pleurotus cystidiosus, Pleurotus sajor-caju and Calocybe indica and two mushrooms novel to Sri Lanka, Pleurotus citrinopileatus and Pleurotus eryngii were inoculated in substrate media bags prepared using selected Jun Cao media and sawdust media. Mycelial growth in each medium was measured, and growth rates, mean yield per substrate bag, and biological efficiencies were compared.Findings and values: The maximum yield of P. djamor [285.20(18.13) g per bag] and P. floridanus [375.6(25.4) g per bag] were from M. maximus based medium and sawdust medium, respectively. The yields of P. sajor-caju, P. cystidiosus, C. indica and P. citrinopileatus in at least one selected Jun Cao medium, M. maximus and C. setosus, were not significantly different from yields of the same mushroom when cultivated in sawdust. The biological efficiencies in sawdust were not significantly higher than those of Jun Cao media. The exotic mushroom P. eryngii was successfully cultivated in Nuwara Eliya, Sri Lanka, using Jun Cao and sawdust-based media while C. setosus based medium gave the highest yield [642.4(41.61) g per bag] and the highest biological efficiency [217.03(14.05) %]. These two grass species can successfully be utilized as alternatives substrates in mushroom cultivation.