Toby Kiers talks fungi in interview with We Are the ReGeneration


© Photo by Gabriela Hengeveld

"Farmers of the future will work together with their fungi", Toby Kiers said in an interview with We Are the ReGeneration, published last month under the same title. In her interview, Toby delves into the rising scientific interest in fungi, the changing public opinion of fungi, and how fungi are going to play an essential role in agriculture. The article is written in Dutch and can be accessed in the link above; an English translation of the article follows below.


(original text written by Paul Q. de Vries)

Toby Kiers: Farmers of the future will work together with their fungi

With every new discovery on fungi, we stand perplexed again and again. Fungi are an essential link to all life on Earth, and therefore, also to agriculture. Toby Kiers has studied fungi since she was 19 years old and won the prestigious Spinozaprijs last year for her groundbreaking research. "Our understanding of fungi will usher in a new era of connecting the pieces."


Fungi have become quite a hot topic since recently, not just to scientists, but also the general public. Why do you think that is?

"Scientific publications about fungi have been around for decades, but they have long been under the radar to the general public. Similar to how fungi themselves have remained under the radar, largely owed to their underground and discrete nature, as well as their minuscule size. But this is changing: multiple movies, documentaries and books about fungi have emerged the past couple of years. Fungi were recently on the cover of National Geographic for the first time, an IMAX-documentary was released narrated by the singer Björk, and people ask me all the time about the HBO-series The Last of Us. The latter is a dramashow about fungi which takes over human brains and turns their host into mindless zombies - purely fictional of course, but based on what real-life Cordyceps fungi do in certain insects. Fungi are fascinating organisms with phenomenal superpowers, so I can see why they appeal to the imagination so much. That sort of enthusiasm will lead to more interest in fungi, which I'm only a supporter of."


How do you explain this interest in fungi?

"It's because they are peculiar beings: appearance-wise, they are most similar to plants, yet they behave more like animals. But in the end, they are neither as they belong to their own kingdom of life on Earth. They are an unexplored realm for studying, which is quite rare these days. Researchers studying fungi are mycologists, but are sometimes jokingly referred to as "myconauts", which demonstrates well how fungi are becoming a new frontier for exploration. Nowadays, we also have the technology to visualise (in high resolution) what fungi are capable of using time lapse videos. I guess that helps too."


"About 59 percent of all life on Earth is found belowground, which makes it the most biodiverse habitat in the world"


In doing so, we are continuously discovering the importance of fungi to sustaining life on Earth.

"Precisely. Fungi are at the base of all life and their ecological impact is immense. About 400 million years ago, they engaged in a symbiotic relationship with plants resulting in immense networks of hyphae and plant roots, also known as mycorrhiza. Plants provide sugars and fats to this network through photosynthesis, while fungi provide minerals like phosphorus and nitrogen from below the ground. Moreover, mycorrhiza play an important role in the carbon cycle: on an annual basis, plants store billions of tonnes CO2 in the mycorrhiza. So, they are also incredibly important to our climate. But their spores also play a role in cloud formation over the Amazon rainforest, just to give you another example."


So are we starting to realise how much we need fungi?

"Slowly, but surely. There is also a huge amount of applications for fungi which clearly and directly benefit society. You can make furniture out of mycelium, which is what fungi are made of. Fungi can also be deployed to clean up persistent pollution, such as oil and plastic. There is even experimentation with microdosing and therapeutic use of hallucinogenic mushrooms. Through all these applications, fungi give us a new hope. It turns out there is so much possible, which I think explains the hype around fungi nowadays. But for me, as a scientist, the mycorrhiza are the most important."


You research the transactions between plants and fungi in their underground network, what are you looking at specifically?

"We follow how nutrients in so-called 'trade deals' are transported through the fungi and plant roots. We see that fungi transport minerals and other nutrients to locations where they are scarce. That way, they will receive more sugar and carbon in return - scarcity drives demand, so to speak. They even temporarily stock up on nutrients, only to release them once they turn scarce. That way, they keep supply low and price high. In highly competitive environments, they even behave differently, because they need to consider they might get overbid or that another is offering for a lower price. You could call this economic behaviour. We are using mathematical models from economical science to predict what fungi will do."


"Fungi help crops by protecting them against plagues"


Sounds like fungi are capable of trading, perhaps they should be considered intelligent?

"These are evolutionary strategies. There has long been resistance against thinking of fungi in such terms, but nowadays it's become widely accepted. Fungi absolutely do trade, and they make decisions. I prefer to avoid the term 'intelligent' - we associate that with the brain and fungi don't have one. I like to say they are beings capable of processing information. Much like plants, by the way. We have to considerably change the way we think in order to grasp that. We kind of need a new model to explain choice-making and consciousness to fully understand how plants and fungi act."


If mycorrhizas are this essential to plant life, does that mean this is also the case for agriculture?

Let me answer this one with some numbers. In a healthy grassland, fungi can amount to about 30-50% of biomass. They form a kind of net which prevents nutrients from flushing away. Plants receive up to 80% of their phosphorus and 30% of their nitrogen from their symbiosis with fungi. Plants could excpand the area on which they grow with a factor of 10 to 100 if their roots are well connected with mycorrhiza. Plants that are connected with fungi, are more efficient at producting chemicals which repel herbivores and insects. Therefore, fungi help crops by protecting them against plagues. Flowers are even larger and have a sweeter scent when plants are connected to mycorrhiza, so fungi even affect pollination dynamics."


In regenerative agriculture, there is a lot of attention to soil and soil life. Is it then mostly about fungi?

"Fungi are an essential element of healthy soils. Other organisms such as bacteria and insects are equally as important. About 59 percent of all life is found belowground, which makes it the mostbiodiverse habitat in the world. That soil life is essential to agriculture. There's a lot of research going into soil transplantation nowadays. Here, you take soil from for example a forest, and transfer it to an agricultural field in poor condition with the intent that the soil life will propagate from there and restore the soil. This could take years, but this way you can at least develop a healthy underground ecosystem. This does not mean we should start excavating forests all around for their soil, that would be taking a wrong turn. And we should take care to keep the soil biodiversity intact. You don't want every agricultural field to have the same soil life composition, then you would get a monoculture again."


What about mycorrhiza in fields subjected to intensive, industrial farming?

"You'd still find mycorrhiza there, but they'd have it quite tough. Pesticides, sometimes even fungicides which are specially designed to combat fungi, artificial fertilizer, mechanical tilling: this is all bad news for fungi. In these agricultural fields, mycorrhiza are more scarce, thinner, and less diverse than in natural soil. The fungi do produce more spores compared to natural soil, but this is because there is more evolutionary pressure to reproduce fast. The most gnarly effect of plants grown on artificial soil is that they are not dependent anymore on fungi for their nitrogen fixation. As a result, fungi will stop trading carbon. You can even see this happening when a farmer does not use artificial fertilizer: there is so much nitrogen circulating in the Dutch environment, you can even find it in the rain."


"Farmers should provide just as much attention, care and knowledge to the invisible belowground life, as they would for the crops that grow aboveground"


What should farmers do if they want to take good care of 'their' fungi?

"It's more about what they probably shouldn't do: use of artificial fertilizer, pesticides, mechanical tillage. There's much talk about planting flowery patches or hedges around agricultural fields. Not only does this increase biodiversity aboveground, but it also forms a great reservoir from which fungi can start recolonizing surrounding fields. But the most important thing we should realise is that our food comes from a system in which fungi are an incredibly important player. That's why farmers should hand over stewardship of the soil to the organisms that inhabit them. Farmers should provide just as much attention, care and knowledge to the invisible belowground life, as they would for the crops that grow above ground."


How can science help farmers?

"At the moment, farmers only have access to rather crude materials. You could for example buy a pot of fungi at a wholesale and inject that into you land, but since those are mainly commercial products, we don't know whether they'd actually help. Even worse: these products could drive away already existing fungi from their land. We have to go back to the basics: how do you treat your soil in such a way that you let already existing fungi and other soil life do their job? How that works, is what's being researched in various projects around the world under the flag of SPUN, a non-profit institute which conducts research into fungi and mycorrhiza. This includes researching how fungi from a surrounding forest spread into adjacent agricultural fields in Ecuador. In the Chilean Atacama-desert, the soil is dry and soil - very inhospitable to plants. Yet, there are green oases all around which the local population uses for farming. We also take soil samples there to see which fungi and mycorrhiza are active there."


"We should be cultivating our crops in a way that optimises their symbiosis with fungi, but we are doing the exact opposite"


Letting fungi do the work: that sounds like a completely new way of farming

"For long, farmers have regarded fungi as a plague or disease, one which they should protect their crops from. And for good reason! There is a humongous amount of fungal species; some of which can destroy entire harvests. But the value of mycorrhiza is impeccable. We should be cultivating our crops in a way that optimises their symbiosis with fungi, but we are doing the exact opposite. For one, by continuously relying on artificial fertilizer. In healthy soils, we were also quick to focus on abiotic factors such as soil structure. Nowadays, we are seeing a transition in mindset where we've started to see the importance of soil life, the belowground biodiversity. There is still much to discover in this field of science. But farmers of the future will work together with their fungi."


Fungi demonstrate that all natural life is connected. Does this insight have consequences that go further than agriculture?

"Absolutely. For long, we've had the tendency to study nature by placing everything in boxes. Everything which had the same properties belonged together. Even when we thought ecologically: a stack of relationships here, a stack of relationships there. But now, it looks like connectivity between species is much more profound and complex than we ever though. We should not be looking at individuals or even individual species, but rather at relationships. We can include that idea in our image of nature as a whole, including our own role as humans in it. You could say our understanding of fungi will usher in a new era of connecting the pieces.


Translated by Julian Voet