Our fantastic neglected fungi

Analysis: This month at the UN Convention on Biological Diversity during the COP16 meeting in Colombia, Chile and the UK called for “funga” to be placed alongside animals (fauna) and plants (flora) as a separate kingdom, as part of a “pledge for fungal conservation”. If successful, this would advance the status of mushrooms, moulds, yeasts, and other members of the fungal kingdom which would hopefully lead to recognition of the need to understand and conserve a life form that is the least-described. As a mycologist, I would ask, what took us so long?

I discovered fungi as an undergraduate student when I was stuck on a tramp and noticed some bright orange mushrooms. I saw them everywhere after that, and when it came time to choose an honour’s project, I knew I wanted to work on fungi. The more I learn about them, the more I realise how little we know about this fascinating kingdom. Close to 30 years later, fungi continue to amaze me.

When I tell people what I do for a living, I am greeted by three predictable responses: “Eewww, moulds”, “Which ones are good to eat?”, and “Where can I find those mushrooms?” All those responses point to the lack of understanding of what fungi contribute to our world; without fungi, our world would not look the same.

Moulds are essential in decomposing dead matter, and without them we would be smothered by mounds of dead plants and animals. The mould Penicillium not only acts as a decomposer, but has also given us the life-saving antibiotic penicillin.

Fungi are marvellous multi-taskers. Many of those that end up on our plate are decomposers in their day job, such as portobellos, which are the mature stage of the white button mushroom.

Some have beneficially symbiotic relationships with plants such as mycorrhizae, which means “fungus root” and are ubiquitous in the soil; many prized edibles such as truffles, chanterelles and porcini are mycorrhizal fungi. About 90 percent of plants are associated with mycorrhizae; while the fungus gets food in the form of carbon from the plant, the plant gets so much more from the fungus, such as access to nutrients that the plant can’t access otherwise. Porcini and chanterelles grow with specific tree species, and those tree species can’t live without their association with these mushrooms.

Where would we be without fungi? We wouldn’t have baker’s yeast that is used to make bread and brew beer, or Marmite that is made from yeast, a by-product of beer brewing. We need mould to make citric acid, upon which most soft drinks depend. Even Lego uses an enzyme produced by fungi in its production process.

Some fungi are poisonous to humans; there is no sure test for edibility other than being able to correctly identify a species – I always tell people if they’re going foraging for mushrooms to stick to a couple of easy-to-recognise species or just buy them at the grocery store!

We often have a love-hate relationship with fungi as anyone who has had thrush, athlete’s foot, or ringworm will testify. So does the plant world. An invasive fungus that causes myrtle rust is attacking some of our native plants such as pōhutukawa and ramarama. Austropuccinia psidii, which causes myrtle rust disease, is an example of a pathogen that is detrimental to another living organism. In my research, we have found that other fungi living within pōhutukawa may help reduce the severity of myrtle rust symptoms.

Even though people have known about fungi for hundreds of years, fungi have been recognised as a kingdom of life only since 1969. Fungi were treated as “lower plants”, but they are more closely related to animals than to plants. It seems fungi are now going through a renaissance and finally getting the recognition they deserve. We still don’t know how many species of fungi there are in the world, and estimates range between 1.5 million to 30 million species, but we have only described fewer than 120,000 species. Even in New Zealand, we have only described a third of the species; 8000 down, 16,000 or so more to go! (I always joke that I am going to name a fungus after my mother, which would get me out of forgetting Mother’s Day for ever.)

In this time of the biodiversity crisis, we need to protect fungi and get serious about fungal conservation. Some species of New Zealand fungi have been assessed through the IUCN Red Listing process: three are critically endangered, 12 are endangered, and nine are vulnerable. But we are losing fungi before they have even been described. It is about time this hyperdiverse kingdom is recognised alongside other threatened species. Raising awareness of this important kingdom of life is long overdue.

Dr Maj Padamsee is a senior lecturer in the School of Biological Sciences, University of Auckland, and a curator of the New Zealand Fungarium at Landcare Research