The team investigated the effects of enriching mushroom casing a layer of material typically peat moss used to retain moisture in mushroom beds by incorporating casing from a previous crop. This process called passaging transfers a portion of the microbiome from one crop to the next.

Their findings revealed that mushrooms grown in microbiome-enriched casing reached their pinning stage where the fungi begin to fruit earlier than those grown in standard casing. These mushrooms also exhibited greater resistance to bacterial blotch a common mushroom disease. However they were more susceptible to another frequent infection green mold disease when exposed to its pathogen.

These diseases are economically significant causing substantial crop losses in button mushroom cultivation O’Connor said. By addressing these challenges this research supports the development of sustainable mushroom farming practices and provides a model for studying how microbiomes influence horticultural productivity.

To conduct the study the researchers first grew a standard crop of button mushrooms and collected the casing after the fungi began fruiting. This casing, which by then likely contained a microbiome adapted to button mushrooms was mixed with fresh casing in a 1:10 ratio.

The researchers found that enriched casing significantly suppressed bacterial blotch. Mushrooms grown in this casing were less likely to develop symptoms and those that did showed milder cases compared to mushrooms grown in standard casing. However the enriched casing exacerbated green mold disease leading to lower mushroom yields when inoculated with T. aggressivum compared to standard casing under the same conditions.

This research was supported by the Huck Innovative and Transformational Seed Fund the Pennsylvania State University J.B. Swayne Faculty Research Endowment in Mushroom and Spawn Science the Pennsylvania State University Mushroom Industry Endowment and the Agriculture and Food Research Initiative of the U.S. Department of Agriculture’s National Institute of Food and Agriculture.

Source: https://www.psu.edu/news/agricultural-sciences/story/harnessing-mushroom-microbiomes-better-crop-development