The Life Cycle of Agaricus Bisporus

The Life Cycle of Agaricus Bisporus
••• Elena Sapegina/iStock/GettyImages

If you or your parents have ever enjoyed some tasty mushroom slices on your pizza or enjoyed an appetizer of stuffed mushrooms while dining out at your local restaurant, you've encountered the incredibly popular mushroom species ​Agaricus bisporus​. In fact, this mushroom species makes up about 90 percent of the mushrooms produced and consumed in the United States!

The Quintessential Mushroom

Scientists estimate that literally millions of different species of mushrooms exist on the planet. Despite this, ​Agaricus bisporus​ is so popular that most people simply call it a "mushroom." ​Agaricus bisporus​ is also referred to as the white button mushroom, table mushroom or pizza mushroom.

This mushroom species is even the same as the portobello mushroom, which is just ​Agaricus bisporus​ grown for a longer period so that its cap reaches a larger size. To many people, particularly in the United States, essentially no other type of mushroom exists.

The Mushroom Life Cycle

Agaricus bisporus​ has a similar life cycle to most types of mushrooms. Like any fungus life cycle diagram, it is cyclical in nature, with adults producing spores that grow, develop and eventually reach an adult phase and produce spores of their own.


The first stage of the ​Agaricus bisporus​ life cycle is inoculation. Floating mushroom spores eventually settle onto a hospitable surface or substrate. If this location has the right conditions for the mushroom to survive, the spores move to the next stage – germination.

Spore Germination

During the spore germination stage, individual spores begin to grow tiny filaments known as ​hyphae​. Male and female hyphae in close proximity come together to produce fertile mycelium. This ​mycelium​ is similar in fashion to the roots of true plants.

Mycelial Expansion

This portion of the life cycle constitutes the mycelium growth stages, or the period where the mycelium of the fungus expands and develops. This growth occurs exponentially. The mycelium works to break down organic matter and absorb the nutrients released to fuel its continued growth. The mycelium also contains protective components to repel competitors and deter predators.

Hyphal Knot

In this stage of the life cycle, the mycelium begins to grow upon itself and condense into a knot-like structure. This structure, known as a ​hyphal knot​, gives rise to the eventual "body" of the mushroom. The mycelium produces many hyphal knots and primordia during this phase.

Primordia Formation

As the hyphal knot condenses and forms, it eventually becomes a primordia. This ​primordia​ is essentially a miniature version of the adult mushroom. A single mycelium produces as many as a thousand small primordia across its surface. Not all of these primordia form into the adult "fruiting body" of the mushroom.

Fruitbody Selection

Only the fastest-growing and most productive of the primordia will develop into fruiting bodies. Each individual fruitbody is what you think of when you imagine a "mushroom." However, these fruiting bodies are not separate organisms, but a single organism connected by its mycelium. These fruiting bodies continue to grow and develop into the adult form of the mushroom.

Mature Fruitbody

As the mushroom reaches maturity, it focuses its growth into the ​fruitbody​, which it will eventually use to reproduce. The mushroom continues to grow and develop until it reaches full maturity and produces spores. The ​Agaricus bisporus​ mushroom that you eat in your meals is the fruiting body portion of the mushroom.

Spore Release

During this final stage in the life cycle, the mature fruitbody releases large volumes of microscopic spores into the air. The mushroom releases the spores from the gill structure on the underside of its cap. These spores eventually descend onto a surface and begin the life cycle again in the inoculation phase.

Related Articles

How to Identify Wild Mushrooms in North Carolina
Characteristics of Mushrooms
How to Identify Wild Psilocybin Mushrooms
Types of Mushrooms in South Carolina
What Are Mycelia in Microbiology?
How Do Fungi Reproduce?
Life Cycle of Obelia
Parts of a Fungus
Edible Mushrooms That Grow on Tree Bark
How Does Duckweed Reproduce?
Types of Fungi Plants
How to Tell Good & Bad Morel Mushrooms
How to Identify Poisonous Mushrooms
What Kind of Environment Do Fungi Like?
How Do Mushrooms Reproduce?
The Disadvantages of Fungi
How to Make Mushroom Spawn
Diagram of the Parts of a Flower
Meet Ophiocordyceps, the Fungus that Turns Ants Into...