Moss Has a Fungal Partner

For decades, moss biology seemed settled. All 10,000 species were thought to live solo: no fungal partners, no mycorrhizal arrangements, just moss doing moss things. Researchers at UC Riverside have now found fungi living inside desert moss tissue, quietly breaking a rule nobody thought needed checking.

More than 85 percent of land plants partner with fungi in a well-documented exchange: nutrients from soil for sugars made through photosynthesis. About three-quarters of those partnerships involve arbuscular mycorrhizal fungi, or AMF. Mosses were considered the exception. For decades, scientists believed all 10,000 species went without.

The team pulverized moss tissue in the lab and screened it for fungal genetic material. They found it. More strikingly, they found mycorrhizal fungi, organisms that cannot survive without a living plant partner. The fungal species inside the mosses didn't match those in the surrounding soil, ruling out random contamination or fungi feeding on dead tissue.

The mosses also contained arbuscule-like structures inside leaf cells, the tiny fungal growths plants use to exchange nutrients. Fungal communities differed between arid and milder sites, suggesting the partnerships were not random and may help desert mosses tolerate heat and drought.

Should the results hold, they would overturn established assumptions about moss biology and force a rethink of how plants first moved onto dry land some 470 million years ago. The plant–fungus partnership seems to be far older and far less optional than textbooks allow.

Mosses have been living on bare rock since before trees existed, getting the same fungal help as the rest of the plant.

Read the full story at Phys.org, June 18, 2026

Hot Take: Moss built a reputation on being unique and fiercely independent. It turns out moss has been on fungi's health plan since before trees existed.