Growth Performance of Pleurotus ostreatus and Pleurotus djamor on Different Agar Media under Laboratory Conditions

Abstract

Pleurotus species are widely used in mushroom cultivation and fungal biotechnology due to their rapid mycelial growth, efficient lignocellulosic degradation, and adaptability to diverse substrates. The present study was conducted to comparatively evaluate the mycelial growth behaviour of Pleurotus ostreatus and Pleurotus djamor on different culture media under controlled laboratory conditions. Three commonly used media, namely Potato Dextrose Agar (PDA), Malt Agar (MA), and Water Agar (WA), were used to assess differences in radial growth, colony morphology, growth progression, and contamination susceptibility. The experiment was carried out using a Completely Randomized Design (CRD) with six treatment combinations maintained in triplicate. Observations related to mycelial growth were recorded on Day 1, Day 3, and Day 5 of incubation. Among all treatments, Pleurotus ostreatus grown on Potato Dextrose Agar exhibited the fastest radial expansion, dense mycelial network, and uniform colony development, followed by Pleurotus djamor on the same medium. Malt Agar supported moderate growth for both species, whereas Water Agar showed comparatively sparse and slower mycelial development due to limited nutrient availability. The overall growth trend observed in the study followed the order PDA > Malt Agar > Water Agar. A consistent observation across all media was the comparatively superior growth performance of P. ostreatus over P. djamor, indicating species-specific differences in nutrient utilization and growth adaptability. Nutrient-rich media such as PDA and Malt Agar also exhibited comparatively higher contamination incidence, whereas Water Agar showed minimal contamination throughout the incubation period. The study highlights the significant influence of media composition on fungal growth behaviour, colony establishment, and contamination susceptibility in Pleurotus species. Although the investigation was limited to laboratory-scale evaluation on agar-based media, the findings provide useful baseline information for fungal growth optimization, maintenance of pure cultures, and future applied cultivation studies involving oyster mushrooms.