INVAM — the International Collection of Vesicular Arbuscular Mycorrhizal Fungi at the University of Kansas — houses more than 900 living fungal strains that support roughly 70% of terrestrial plants. The collection requires annual, expert cultivation and now faces possible closure after NSF funding expired; without new support it may survive only about a year. Studies show most commercial AM biofertilizers are ineffective, underscoring the unique value of a rigorously maintained public repository for restoration, agriculture and basic science.
Defunding Fungi: INVAM — The US Living Library of Soil’s ‘Ecosystem Engineers’ Is at Risk
Left: Fungal spore samples stored in INVAM’s cold room. The collection is a living library, maintaining more than 900 distinct AM fungal strains from six continents.Photograph: Ben Martynoga
Inside a large greenhouse at the University of Kansas, Professor Liz Koziol and Dr. Terra Lubin tend rows of sudan grass grown in individual pots. Each plant’s roots host a specific strain of invisible soil fungus, and a nearby cold room holds thousands of bags and vials of carefully preserved spores. Those samples make up the International Collection of Vesicular Arbuscular Mycorrhizal Fungi (INVAM), the world’s largest living repository of arbuscular mycorrhizal (AM) fungi — and it now faces possible closure within a year because of federal funding cuts.
What INVAM Is And Why It Matters
INVAM preserves living spores from more than 900 distinct AM fungal strains collected from six continents. AM fungi form symbiotic partnerships with roughly 70% of land plants, exchanging sugars and lipids from plants for nutrients such as phosphorus, nitrogen and trace metals. They also help plants withstand drought and disease and act as an important underground carbon sink. Because these fungi disperse slowly and are fragile outside of living culture, a curated, active collection like INVAM is irreplaceable for research and restoration.
Delicate Work — And A Fragile Funding Model
Unlike seeds stored dry or cells kept frozen, AM fungal spores must be cultivated and refreshed each year. Technicians isolate spores under a microscope, inoculate host seedlings (such as sudan grass), grow them in sterile greenhouses for weeks, then stress the plants to prompt new spore production. This cycle must be repeated annually for every strain — a labor-intensive process that relies on skilled staff.
Founded in 1985, INVAM has depended on successive federal grants. Its most recent National Science Foundation (NSF) funding ended in May, and the proposed federal budget for fiscal year 2026 would cut NSF by 57%, increasing competition for limited dollars. Without another grant, curators estimate the collection may survive only about a year before closure becomes likely. The University of Kansas currently covers infrastructure but not staffing, and the collection is operating on short-term grants and volunteer labor.
Practical Consequences: Research, Restoration And Food Systems
INVAM’s value extends beyond academic research: its cultures are used to restore degraded landscapes, rebuild damaged soils and reduce reliance on synthetic fertilizers. Field trials near Lawrence, Kansas, illustrate this potential. In 2016, curator Liz Koziol seeded a former hayfield with native prairie species and inoculated plots with AM spores from remnant prairie fragments. Nine years later, inoculated plots are far more diverse and vigorous than control plots that received seeds but no fungi.
Modern agriculture — fungicides, heavy fertilizer use and tillage — often eliminates AM fungi from farmland, making reinoculation essential for many restoration projects and potentially beneficial in perennial and some annual cropping systems. Programs such as the Conservation Reserve Program (which enrolls more than 20 million acres) could see larger returns if reinoculation with native mycorrhizal fungi were integrated into restoration policies.
Commercial Market Fails To Match Public Science
The private market for fungal biofertilizers is growing — valued at about $1.29 billion globally — but quality is a major problem. In a 2024 study, researchers tested 23 commercial AM products and found 87% failed to colonize plant roots; many contained dead spores, no viable inoculum, or even plant pathogens. Larger studies in Europe and a 2024 meta-analysis reached similar conclusions. INVAM and other public collections provide rigorously maintained, traceable strains that are needed for trustworthy research and reliable restoration work.
Science Still Has Big Questions
Beyond practical applications, living collections enable fundamental research. Scientists rely on INVAM cultures to investigate basic mysteries — for example, why AM fungal cells contain thousands of nuclei and how distinct strains can exchange cellular material. Many of these questions cannot be answered without access to living, well-characterized strains.
Voices From The Field
“INVAM represents a library of hundreds of millions of years of evolution,” said mycologist Toby Kiers. “Ending INVAM for scientists is like closing the Louvre for artists.”
Merlin Sheldrake added: “These organisms are vital ecosystem engineers that hold the key to so many problems we face. To lose this library would be an unimaginable tragedy.”
What’s At Stake
If INVAM closes, decades of carefully maintained, living fungal diversity would be at risk — undermining restoration projects, trustworthy biofertilizer development and basic mycological research. While private donations might help in the short term, the curators and researchers emphasize there is no real substitute for sustained federal investment in public biological infrastructure.
