Evaluating Regional Agricultural Wastes as Substrates for the Mycelial Growth and Fruiting Body Yield of Pleurotus ostreatus

Author

Daniel RhinerFollow

Date of Award

Summer 7-15-2020

Degree Type

Thesis

Degree Name

Master of Science in Integrative Biology (MSIB)

Department

Biology

Committee Chair/First Advisor

Susan M. E. Smith, PhD

Major Professor

Christopher T. Cornelison, PhD

Second Committee Member

Thomas McElroy, PhD

Third Committee Member

Donald McGarey, PhD

Abstract

Pleurotus ostreatus, commonly known as the oyster mushroom, is a widely cultivated culinary mushroom known for its ability to colonize a variety of lignocellulosic agricultural wastes. The ability of P. ostreatus to utilize these types of wastes as growth substrates suggests a potential for this organism to convert agricultural waste streams into locally productive and regenerative systems. Agriculture is a leading contributor to Georgia’s economy, but it also produces large amounts of plant-based agricultural wastes of little to no value. Repurposing these wastes into profitable culinary and medicinal mushrooms has become an increasingly appealing approach to mitigating these wastes. To investigate the use of Georgia’s regional agricultural wastes as mushroom growth substrates, pecan shells, peanut shells, cotton gin waste, spent brewing grains, wheat middlings, hardwood sawdust, and corn chaff were used to measure the mycelial growth and fruiting body yields of two commercial isolates and four local isolates of P. ostreatus. Biological efficiencies and colonization times were calculated for all harvested mushrooms. Metabolic phenotyping methodologies were also developed to better pair each isolate with specific agricultural wastes. Substrate moisture content further characterized optimal biological efficiencies and colonization times for each isolate on each agricultural waste. This data addresses the knowledge gap regarding the use of regional agricultural wastes as commercial feedstocks for mushroom cultivation in Georgia, and the potential of local mushroom isolates to colonize and produce fruiting bodies on these wastes at a commercial and profitable scale.