Cultivating oyster mushrooms on invasive plants : an alternative substrate

Invasive plant species are taking over forests and other ecosystems globally, creating a large reservoir of unused lignocellulolse biomass. In the upper-midwest, buckthorn (Rhamnus cathartica) and honeysuckle (Lonicera maackii) are two prevalent woody invaders of forest ecosystems. The objective of this study was to determine if these forest exotics could be successfully used as a sustainable alternative substrate for mushroom cultivation. Since Pleurotus species produce a wide array of lignocellulolose degrading enzymes and can break down many different substrates and contaminants, members of this genus were chosen for the study. Two strains of the fungus were chosen for this study; one that is used in commercial cultivation practices and one that was isolated from a fruiting body found growing near the invasive plants used in the study. The two strains of oyster mushroom were grown on buckthorn and honeysuckle along with control treatments of oak and straw. Time to colonization, time to first harvest, first yield, total yield, and biological efficiency (BE) were all measured and then compared to the control treatments. Although both strains of Pleurotus performed best on the straw substrate, there was no significant difference within a strain of the yield and BE on the buckthorn, honeysuckle, and oak substrates. These results suggest that invasive species can provide an alternative sustainable substrate compared to currently used hardwood woodchips