Brown Cap Mushroom Virus

This page offers an introduction to Brown Cap Mushroom Virus, how the disease is spread and how to identify the signs of an outbreak. You can also read recommendations on how to prevent and control the disease.

Original authors: Caoimhe Fleming-Archibald, Kerry Burton and Helen Grogan.

Brown Cap Mushroom Virus causes brown or off-white colouring in white mushrooms and is associated with Mushroom Virus X. Outbreaks tend to occur sporadically every year and have been linked to hygiene issues with bulk Phase 3 compost.

The virus has been detected at compost facilities, growing facilities, during transportation, or during filling or emptying operations. Improved hygiene at all points of the mushroom production process is the key to preventing or reducing the risk of contamination from Brown Cap Mushroom Virus.

Learn more about Brown Cap Mushroom Virus and its symptoms. These range from discolouration to general poor crop quality.

Read our findings about how Brown Cap Mushroom Virus spreads and how to identify potential infection points in the production process.

You can detect and control outbreaks of Brown Cap Mushroom Virus by testing regularly and following strict hygiene rules. See our recommended strategies for managing the disease and preventing reoccurrence.

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