What Is Mycology? The Study of Fungi Explained

Mycology is the scientific study of fungi: the yeasts, molds, mushrooms, rusts, smuts and microscopic filamentous organisms that make up one of the major kingdoms of eukaryotic life. Mycologists ask how fungi grow and reproduce, how they are classified and how they evolved, how they decompose organic matter and partner with plants, how some of them cause disease in people, animals and crops, and how others are put to work in medicine, food and industry. This guide explains what mycology covers, its major subfields, the methods and collections the field relies on, how mycology research is funded, the biosafety questions that fungal work raises, and the usual training path into the field.

What Is Mycology?

Mycology (from the Greek mykes, “fungus”) is the branch of biology devoted to fungi. Fungi are neither plants nor animals. They form their own kingdom, and molecular phylogenetics has shown they are more closely related to animals than to plants. Most fungi are heterotrophs that digest food externally: they secrete enzymes into their surroundings and absorb the resulting small molecules. Many grow as networks of microscopic threads called hyphae, collectively a mycelium, while others, the yeasts, live as single cells. Fungal cell walls contain chitin, and the membrane sterol ergosterol is a characteristic fungal feature that several antifungal drugs exploit.

The field is large because the organisms are numerous. About 2.5 million fungal species was the best estimate in the Royal Botanic Gardens, Kew report State of the World’s Fungi (2018), and a 2017 analysis by Hawksworth and Lücking put the plausible range at 2.2 to 3.8 million species. Only a small fraction of these have been formally described, which means new species discovery is still a central, active part of mycology.

Mycology is a subdiscipline of biology and is usually counted within microbiology, even though many fungi, such as mushrooms and bracket fungi, are far from microscopic. It borders botany (a historical home for fungal taxonomy and the reason many fungal names follow plant-style nomenclature rules), plant pathology (fungi cause a large share of crop diseases), virology (viruses of fungi are called mycoviruses) and immunology (host defence against fungal infection).

Major Subfields of Mycology

• Fungal biology, physiology and cell biology — hyphal growth, spore formation, mating systems, cell-wall construction, secondary metabolism and signalling. Yeasts such as Saccharomyces cerevisiae are among the most important model organisms in all of biology.
• Taxonomy, systematics and phylogenetics — describing, naming and classifying fungi. DNA sequencing has reshaped fungal classification, and the ITS region of ribosomal DNA is the formal DNA barcode for fungi.
• Medical and clinical mycology — fungal infections (mycoses) in humans, their diagnosis, antifungal therapy and antifungal resistance. Pathogens of concern include Candida species, Aspergillus fumigatus, Cryptococcus neoformans, endemic dimorphic fungi such as Histoplasma and Coccidioides, and the Mucorales.
• Veterinary and wildlife mycology — fungal disease in animals, including the amphibian chytrid fungus Batrachochytrium dendrobatidis and white-nose syndrome in bats.
• Plant pathology and agricultural mycology — rusts, smuts, blights and mildews, mycotoxin-producing molds in stored grain, and biological control using fungi.
• Environmental and ecological mycology — decomposition and nutrient cycling, mycorrhizal partnerships between fungi and plant roots, lichens (fungi living with algae or cyanobacteria), endophytes and the fungal component of soil microbiomes. See also soil science.
• Industrial and applied mycology — fermentation, enzymes, organic acids, pharmaceuticals and food. Baker’s and brewer’s yeast, koji molds, cheese-ripening molds and edible mushroom cultivation all belong here, as does the discovery of drugs from fungi. Penicillin from Penicillium is the best-known example, and the immunosuppressant cyclosporine also comes from a fungus. This area overlaps with biotechnology.
• Mycotoxicology and food mycology — toxins such as aflatoxin produced by Aspergillus species, and spoilage in food and feed; see food microbiology testing.
• Fungal genomics and evolution — comparative genomics, population genetics and the evolutionary history of the kingdom; compare genetics and evolutionary biology.
• Ethnomycology and citizen science — the cultural uses of fungi, and the large community of amateur mycologists whose forays and observations contribute to species records.

Medical Mycology and Why It Has Grown in Importance

Fungi were long treated as a minor corner of infectious disease, but clinical interest has risen with the number of people who are immunocompromised: patients receiving chemotherapy, organ or stem-cell transplants, or long-term corticosteroids, and people with advanced HIV. In October 2022 the World Health Organization published its first Fungal Priority Pathogens List, covering 19 fungi grouped into critical, high and medium priority tiers. The critical group comprises Cryptococcus neoformans, Candida auris, Aspergillus fumigatus and Candida albicans. WHO cited both the severity of these infections and the limited pipeline of antifungal drugs, with antifungal resistance ranked as the most important research-and-development consideration.

Candida auris illustrates the field’s infection-control side. It is reported to be often resistant to multiple antifungal classes and can persist on surfaces in healthcare settings, so hospitals treat detection of a case as an infection-prevention event, not only a treatment problem. The shared vocabulary of healthcare-associated infection surveillance is covered in the site’s patient-safety content; the laboratory side, such as culture, identification and susceptibility testing, belongs to clinical mycology and clinical microbiology.

The clinical laboratory identifies fungi through a combination of direct microscopy (for example potassium hydroxide preparations and fluorescent stains), culture on media such as Sabouraud dextrose agar, biochemical tests, mass-spectrometry-based identification (MALDI-TOF), antigen and antibody tests, PCR and sequencing. Antifungal susceptibility testing is standardised by organizations such as CLSI and EUCAST.

Core Methods

• Culture and isolation — growing fungi on selective and differential media and describing colony morphology, pigment, growth rate and temperature tolerance. Aseptic technique is essential, because fast-growing molds contaminate everything; see cell culture contamination for how fungal contaminants behave in a cell-culture lab.
• Microscopy — light microscopy of spores, hyphae and fruiting structures, with stains such as lactophenol cotton blue, and electron microscopy for ultrastructure.
• DNA barcoding and sequencing — ITS sequencing for identification, multi-locus phylogenetics for classification, whole-genome sequencing for pathogens and model fungi.
• Environmental metabarcoding and metagenomics — sequencing DNA directly from soil, wood, air or water to profile fungal communities, a method that has shown how much diversity cannot be cultured.
• Genetic manipulation — gene deletion, CRISPR-based editing and heterologous expression in yeasts and filamentous fungi.
• Chemistry of natural products — extraction, mass spectrometry and NMR to characterise fungal metabolites.
• Field and herbarium work — collecting specimens, drying them for fungaria, recording habitat and depositing vouchers so that species names stay tied to physical reference material.

Culture Collections and Fungaria

Mycology depends on preserved, reference-quality organisms. Two kinds of institution matter. A fungarium (or herbarium) holds dried specimens, including the type specimens that anchor species names. A culture collection maintains living strains, typically cryopreserved or freeze-dried, and distributes them to researchers.

The Westerdijk Fungal Biodiversity Institute in Utrecht, the Netherlands (formerly the Centraalbureau voor Schimmelcultures, CBS) maintains the CBS collection, described as one of the oldest and largest public collections of living fungi, with on the order of 100,000 strains. In the United States, the ATCC (American Type Culture Collection) supplies fungal strains, and the USDA Agricultural Research Service Culture Collection, known as NRRL, holds a large fungal and bacterial collection. The Fungal Genetics Stock Center serves researchers working with genetic model fungi.

Why this matters for research integrity: a published result with a fungus is reproducible only if the exact strain can be obtained. Good practice is to cite strain numbers, deposit key isolates in a recognised collection, and record sequence accessions. Transferring cultures between institutions also involves material-transfer paperwork and, for some organisms, permits, so a collection deposit is often the cleanest way to share a strain.

History in Brief

Fungi were studied as curiosities for centuries before the field became systematic. The Florentine botanist Pier Antonio Micheli, in Nova plantarum genera (1729), described fungal genera and demonstrated that spores could grow into new fungi. In the nineteenth century, work on potato blight and on wine and bread fermentation tied fungi and yeasts to disease and chemistry. Fleming’s 1928 observation of antibacterial activity from a Penicillium mold led, through later work, to penicillin, and the antibiotic era made fungi a source of drugs. Fungi were separated into their own kingdom in the twentieth century (the five-kingdom scheme of R. H. Whittaker, 1969), and the sequencing of the S. cerevisiae genome in 1996, the first eukaryotic genome completed, made yeast a cornerstone of genomics. Molecular methods now drive classification, and the number of fungal pathogens recognised as public-health threats keeps growing.

How Mycology Research Is Funded

Funding depends on the application. In the United States, the main sources are:

• National Institutes of Health. The National Institute of Allergy and Infectious Diseases (NIAID) is the principal NIH funder of medical mycology. It has issued funding opportunities for the discovery and development of novel therapeutics against select fungal pathogens, naming Candida auris, Aspergillus fumigatus, Coccidioides and Mucorales. The National Institute of General Medical Sciences (NIGMS) supports basic work in model organisms, including yeast. Typical mechanisms include the R01 research project grant and, for training, the T32 institutional training grant. How competitive a given institute is can be read through concepts such as the NIAID payline.
• National Science Foundation. NSF funds fungal biology that is not framed around human disease, for example evolution, systematics, ecology and symbioses, through its Directorate for Biological Sciences. The Dimensions of Biodiversity program supported projects integrating taxonomic, genetic and functional diversity, including work on mycorrhizal fungi. See National Science Foundation (NSF); program names and solicitations change, so check the current NSF opportunity list rather than relying on a past solicitation.
• USDA. Agricultural mycology (crop diseases, mycotoxins, biocontrol) is supported through USDA programs, and USDA-ARS scientists run their own research programmes and the NRRL collection.
• Other sources. Foundations, industry (fermentation, pharmaceuticals, food) and international agencies fund work in their own priority areas.

Mycology has often been described by its own community as under-resourced compared with the size of the kingdom and the health burden of fungal disease, so grant writing in this field frequently has to make the case for significance explicitly.

Journals and Societies

The Mycological Society of America (MSA), founded in 1932, describes its purpose as promoting and advancing the science of mycology and fostering research and education in all its aspects. Its official journal is Mycologia, and it publishes a newsletter, Inoculum. The society holds an annual meeting, gives awards across career stages from undergraduate to late career, and runs a Student and Postdoctoral Section.

Other widely read venues include Fungal Biology, Medical Mycology, Journal of Fungi, IMA Fungus and Studies in Mycology. Internationally, the International Society for Human and Animal Mycology (ISHAM) is the main society for medical and veterinary mycology, and the International Mycological Association coordinates the field globally. Because clinical mycology also publishes in infectious-disease and microbiology journals, researchers working across these areas may belong to several societies.

Biosafety Considerations for Fungal Work

Most fungi handled in research are low-risk, but not all, and the main routes of hazard differ from bacteria. Fungal spores are small, abundant and easily airborne, so inhalation is the primary concern. Opening a plate of sporulating mold on an open bench can release a large number of spores. Fungal risk is also driven by who is exposed: an organism harmless to a healthy researcher can be dangerous to an immunocompromised colleague, and fungal allergens and mycotoxins add non-infectious hazards.

Laboratories assign work to a biosafety level based on risk assessment. The CDC/NIH Biosafety in Microbiological and Biomedical Laboratories (BMBL) is the standard U.S. reference, and its agent summaries treat some dimorphic fungi, such as Coccidioides and Histoplasma capsulatum, as requiring more containment when sporulating mold-phase cultures are handled. Work with common non-pathogenic yeasts and molds generally sits at BSL-1, with opportunistic pathogens such as Aspergillus fumigatus or Candida commonly handled under BSL-2 practices, and higher-risk fungal pathogens handled at BSL-3. The assignment for a particular organism and procedure should come from the BMBL, the institutional risk assessment and the institution’s biosafety officer, not from a summary like this one.

Practical controls include working in a biosafety cabinet for aerosol-generating steps, keeping plates sealed, avoiding opening cultures outside containment, decontaminating waste, and good aseptic technique. Many institutions require review of recombinant or synthetic nucleic-acid work, including fungi, by an Institutional Biosafety Committee. For background see biosafety and biosecurity, the BMBL entry, the guide to using the BMBL, and dual-use research of concern, which applies to a defined list of agents and experiments.

Training and Career Paths

Mycologists generally train through a degree in biology, microbiology, plant science or a related field, followed by a PhD in a lab working on fungi, then one or more postdoctoral positions. Fungal expertise is spread across departments: plant pathology, microbiology, ecology and evolutionary biology, and medical schools. Skills that employers and labs look for include culture and microscopy skills, molecular methods, bioinformatics, statistics and, for clinical roles, laboratory certification. Non-academic paths include clinical and public-health laboratories, the pharmaceutical and fermentation industries, agriculture and food safety, environmental consulting, and curation of collections. The MSA’s Student and Postdoctoral Section and regional mycological clubs are common entry points for forays, identification skills and mentoring.

Mycology and Research Administration

For research offices, fungal research touches several recurring administrative topics: grant mechanisms and training grants, biosafety committee review, strain and material transfer, data and sequence deposition, and the recognition of taxonomic and collection work, which produces specimens and names rather than conventional papers. Teams supporting such labs benefit from knowing the relevant institute or program early, since NIAID, NIGMS, NSF and USDA each have different review cultures. The broader family of disciplines is mapped on the Branches of Science guide.

Frequently Asked Questions

What does a mycologist do?

A mycologist studies fungi. Depending on specialty that can mean describing new species, running experiments on yeast or filamentous fungi, diagnosing and treating fungal infections, studying fungal roles in forests and soils, managing a culture collection, or developing fungus-based products and fermentation processes.

Is mycology part of microbiology or botany?

Both claims have history behind them. Fungi were historically classed with plants, and fungal taxonomy grew up in botany departments. Today fungi are a separate kingdom, and mycology is commonly counted within microbiology and biology while keeping close links to botany and plant pathology.

Are mushrooms the same as fungi?

A mushroom is the reproductive fruiting body of certain fungi. The main body of the organism is usually the hidden mycelium. Many fungi, such as yeasts and molds, never form mushrooms.

What is the difference between mycology and medical mycology?

Mycology is the whole study of fungi. Medical mycology is the subfield concerned with fungi that infect or harm humans, including diagnosis, antifungal drugs and resistance, and hospital infection prevention.

Where can researchers get fungal strains?

From public culture collections such as the Westerdijk Fungal Biodiversity Institute, ATCC, the USDA-ARS NRRL collection and the Fungal Genetics Stock Center. Check access rules, permits and any biosafety requirements before ordering or shipping.

What biosafety level is needed to work with fungi?

It depends on the species, the culture form and the procedure. Many common yeasts and molds are BSL-1 or BSL-2 work, while some pathogenic fungi in mold form call for BSL-3 practices. Use the BMBL and your institutional biosafety office to decide.

Which agencies fund mycology research?

In the U.S., chiefly NIH (especially NIAID for infectious disease and NIGMS for basic biology), NSF for systematics, ecology and evolution, and USDA for agricultural mycology, plus foundations and industry.

How is mycology different from virology?

Mycology studies fungi, which are cellular eukaryotes. Virology studies viruses, which are acellular. The two meet in the study of viruses that infect fungi and in infections where both occur.