Comparison of substrates for inoculum and spawn development to enhance mycelial growth of Dictyophora indusiata

Abstract

Dictyophora indusiata is an economically important edible mushroom valued for its health benefits. However, production faces limitations due to extended cultivation periods for spawn and substrate preparation. This research compared materials for inoculum substrate using four cereal grains (sorghum, paddy rice, corn, and mung bean) and three sawdust-based substrate formulations to reduce spawn expansion time. The experiment comprised two parts: (1) inoculum substrate from cereal grains using completely randomized design with 5 replications, incubated at 28°C, with mycelium growth evaluated after 40 days, and (2) sawdust spawn production in greenhouse using randomized complete block design with 3 replications, measuring weekly mycelium growth for 7 weeks. The results showed that sorghum was the most suitable substrate for inoculum production, yielding 92.90% mycelial growth, which was significantly higher than other grains (p ≤ 0.01). For spawn bag development, Formulations 1 and 2 provided the best results, with mycelium fully colonizing the 16 cm substrate bags within 49 days. Formulation 1 consisted of sawdust, lime, Epsom salt, pumice, gypsum, molasses, and fine rice bran, while Formulation 2 contained sawdust, lime, Epsom salt, pumice, gypsum, rice flour, and fine rice bran. Formulation 3, composed of sawdust, lime, Epsom salt, pumice, gypsum, ground Leucaena meal, distillers’ grain, and fine rice bran, resulted in slightly lower growth at 13.63 cm.