S2 E2: Claire Willing and Mycorrhizal Fungi

In this episode of FieldSound, Professor Claire Willing shares her research on the vital plant-fungal interactions hidden below the soil surface, particularly mycorrhizal fungi. Willing discusses their ancient symbiotic relationship with plants and significance in nutrient uptake, soil structure, and plant health.

Willing is an ecologist specializing in microbial ecology, plant ecology, and plant physiological ecology. Willing is the John C. Garcia Professor in the School of Environmental and Forest Sciences. With a primary focus on plant-fungal interactions, particularly those between plant roots and mutualistic mycorrhizal fungi, Willing's lab investigates the intricate dynamics shaping ecosystem health.

https://www.washington.edu/research/new-faculty-spotlight-claire-willing/

https://environment.uw.edu/podcast

Transcript

00;00;00;00 - 00;00;19;03
Sarah Smith
From the University of Washington. College of the environment. This is Field Sound

00;00;19;05 - 00;01;01;10
Sarah Smith
There's no doubt that fungi are fascinating. Fruiting fungal bodies come in all shapes and sizes, often appearing seemingly out of nowhere after a spell of rain. But what's happening below the surface in the unseen world where plant roots intertwine with fungal life? U-dub School of Environmental and Forest Sciences assistant Professor Clare Willing explores the underground intersections of plants and fungi, and what the implications are these tiny yet mighty interactions might mean for our planet's health.

00;01;01;13 - 00;01;24;03
Claire Willing
So just like we have sort of a human gut microbiome, right? Plants have the same thing. And so the roots are really the sort of center of metabolism for plants. It's almost like the gut for plants. And so I study the microbial interactions that take place in what we call a rhizosphere, or the area in and around root systems.

00;01;24;10 - 00;01;52;05
Claire Willing
And so I mainly focus on fungal communities that I do work with bacteria as well, because bacteria and fungi also interact, in really interesting ways. The main focus of my lab is looking at mycorrhizal fungi, which are these mutualistic root associated fungi and they are so cool. so mycorrhizal fungi are what we think allowed plants to move from aquatic systems onto land.

00;01;52;06 - 00;02;29;16
Claire Willing
So the sort of first terrestrial migration of plants before they had roots. And these mycorrhizal fungi basically acted as plant roots, allowing these formerly aquatic plants to kind of colonize land. So they're really ancient symbiosis. and they're super, super important. So the vast majority of plants that form associations with mycorrhizal fungi and the ones that don't actually evolved away from that habit, largely in really severe environments where they probably had issues or trouble actually contacting some of those fungi for that relationship. So the default is to be mycorrhizal for plants. So it's really, really important. 

00;02;29;16 - 00;02;56;23
Sarah Smith
Mycorrhizal fungi are the unsung heroes of an ecosystem. They're crucial in supporting plant life. But how? 

00;02;56;23 - 00;03;28;16
Claire Willing
Mycorrhizal fungi can have, you know, these effects that kind of cascade through the whole system. So mycorrhizal fungi are really important in soil structure, in the stability of soils.So water holding capacity of soils, when you know you have summer droughts or like a, a climate where we have a mediterranee in summer and not much rainfall. So that can be a really important part of having mycorrhizae sort of in the soil system. They also really shift plant access to nutrients. And these mycorrhizal fungi can help plant get at especially nitrogen and phosphorus in the soil that the plant would not have access to because its roots are so much coarser than these hyphae, so just less absorptive surface area, essentially.

00;03;28;17 - 00;03;52;04
Claire Willing
They're also really good at getting a lot of micronutrients. so I think we often think of kind of the big fertilizer nutrients for plants in nitrogen, phosphorus, but plants also need things like zinc and iron and things like that as well. and so mycorrhizal fungi are really important for micronutrient nutrition as well, kind of moving upstream in the plant.

00;03;52;08 - 00;04;25;13
Claire Willing
Mycorrhizal fungi can also have really important effects on, plant hormonal physiology. So, so model conductance or like the signaling of plants apertures on their stomata that like allow CO2 in and water out and then they can also even influence fruiting patterns. Fungi influence a number of like flowers and fruit production, the quality of fruit production. So it really goes like the whole way through the plant life cycle from like establishment and germination all the way through reproduction and fruiting.

00;04;25;14 - 00;04;51;11
Claire Willing
And so yeah, they, they play a really important role in nutrition, immune systems for plants, just kind of like the whole thing because they've co-evolved for, you know, millions of years. And there are so important for the health of like every ecosystem. so desert soils have fungi. rainforest soils have fungi. Yeah. It's a it's a really cool and ancient relationship and.

00;04;51;13 - 00;05;28;16
Claire Willing
Yeah, super, super important. 

Sarah Smith

Fungi are everywhere supporting plant life, affecting soil health. We're fast approaching peak gardening season here in the Pacific Northwest. If fungi are crucial in supporting the health of our own gardens, what can we do to better protect their integrity in the context of sort of gardening and and that sort of more urban interface over fertilizing 
can have a really big impact on fungal communities.

00;05;28;18 - 00;05;57;18
Claire Willing
so plants are less likely to associate with mycorrhizal fungi, for example, if there's an abundance of, phosphorus or nitrogen in the soil. Okay. Yeah. And so that can kind of slowly degrade health of soil over time. So I think being aware of the types of fertilizer you might apply or the types of amendments in general, and then also, you know, tilling soil can be really detrimental for, the health of those high fees.

00;05;57;18 - 00;06;16;25
Claire Willing
So thinking a little bit about like, yeah, how you physically treat this soil, what you're putting on it. Yeah. All those types of things can, can be an influence on the communities. 

00;06;16;28 - 00;06;26;06
Sarah Smith
It's interesting. Yeah. There's so, like, there's so much we could talk about. And then of course I'm talking about like. But what about my garden this year? I want my tomatoes to grow.

00;06;26;08 - 00;06;56;09
Sarah Smith
Willing joins researchers across disciplines working to address complex issues and impacts associated with climate change. With a focus on fungal community ecology and the far reaching impacts of fungal community health. 

00;06;56;09 - 00;07;31;13
Claire Willing
Our lab mainly focuses on forest microbiome farms and climate change. And so the sort of center of our work is looking at how do fungal communities shift in response to lots of different climate change factors. So drought, fire, elevational range shifts, basically all of these different factors where we see a lot of shifts, associated climate change. I think climate change is, very challenging topic in a lot of ways. But I think intellectually it's also really interesting. And so it can influence so many aspects of biology and ecology. One is through, you know, if species are needing to migrate, some species basically have what we have categorized as like four major responses to climate change.

00;07;31;16 - 00;07;57;05
Claire Willing 
They can adapt. So have like some sort of genetic evolution that happens that allows them to live in that place that is now in a different environment. They can acclimate, which means that they can sort of adjust their physiology or function in in ways that allows them to kind of cope with a new environment. So that's not, you know, any sort of genetic change.

00;07;57;05 - 00;08;31;00
Claire Willing
It's more just like a plastic response we call, and then if they don't do either of those, they can migrate. And so that's kind of the movement of species either upslope or poleward, towards more suitable habitat. And it could also involve micro climatic buffering. So moving to, you know, habitats on a landscape that maybe still sort of have the, historical climate that is that is preferable for that organism.

00;08;31;03 - 00;08;53;15
Claire Willing
If they don't do any of those things, then you face extinction. Right. And so that might be like local extinction. It might be extinction, of that species entirely. So there's a lot of different ways that we can think about that. But those are kind of the core responses. And so I have a grad student who's really interested in this idea of migration and elevational range shifts.

00;08;53;18 - 00;09;14;25
Sarah Kowski
So this is my first year here insects. And my name is Sarah Kowski they them pronouns a lot of kind of the area focus fits under what Claire was talking about. But more specifically, I'm really interested in forest green shifts under climate change. and kind of what is happening with the mycorrhizal community associated with those forestry, those those green shifts.

00;09;14;25 - 00;09;39;28
Sarah Kowski
So, one of the area, the areas that we're looking at is kind of Mount Tahoma, Mount Rainier area and thinking about the subalpine fir that are going upwards in elevation. a lot of that driven by like temperature changes and trying to understand, like are one are the fungi moving with, is that actually what's happening? And if they are, which species are getting there first?

00;09;39;28 - 00;10;03;22
Sarah Kowski
How is that influencing the tree establishment and how it is, kind of interacting with other plants in that system. So in these meadow alpine systems. 

00;10;03;25 - 00;10;31;04
Claire Willing
So there's been a lot of work, in the broader university by, some other folks, some colleagues of ours looking at Abbey's which is subalpine fir and how it's basically encroaching into these subalpine meadows. And so it's moving upslope. And we're really interested in understanding if these fungi play a role in the establishment of that tree. If basically the wind patterns of fungal dispersal might be able to help us predict where those fungi are getting in contact with those trees, and if that's essentially allowing those trees to outcompete other local flora and those environments.

00;10;31;06 - 00;10;59;28
Claire Willing
and so it's been a really fun project, kind of getting off the ground with all of this and, and thinking about how to measure fungal dispersal, wind, all these different sort of factors. My postdoc, I was doing a lot of work with plant species coexistence. and so I was really interested in how we might measure the contribution of mycorrhizal communities to plant species coexistence.

00;11;00;02 - 00;11;33;28
Claire Willing
And in my in a paper that's sort of forthcoming now, we looked at the role of two different types of mycorrhizal fungi and potentially enabling competitive exclusion of a species over another, or allowing for coexistence of those species. And what we found is that one particular type of mycorrhizal fungi promoted coexistence between those species. So if that mycorrhizal fungus in general was, missing from the system, you would get competitive exclusion.

00;11;34;02 - 00;12;04;05
Claire Willing
And basically pine would dominate that system. When that fungus was present. It really up to the probability of having coexistence in that system. And so basically that means that the presence or absence or the potential dispersal of that fungus could have really major implications for which plants are on the landscape. And then all of the sort of cascading effects of, of ecosystem function from there.

00;12;04;05 - 00;12;44;23
Claire Willing
Right. So yeah, yeah, it was it was really interesting kind of getting to measure some of these things and create this like experimental setup to be able to measure some of this. And so yeah, we're really interested in in being able to apply this in a climate change context to this system and better understand if, if those spores of that fungus can get into this location where it maybe previously hasn't been able to get, how would that tip the scales of coexistence potentially in that system towards a FIR dominated system, for example?

00;12;44;26 - 00;13;10;17
Sarah Smith
Wellings own grad student experience informed what she's trying to do here at Udo, but what inspired her initial path in science and the pursuit of a PhD? 

00;13;10;19 - 00;13;37;21
Claire Willing
I grew up in a really small town in southern Oregon, and I never thought about being a scientist that wasn't on my radar at all. I don't think I'd ever met anyone with a PhD before I went to college. But when I got to college, I, I sort of stumbled around between fields and eventually stumbled into biology and ecology and I think growing up in a very, like, forested place, I felt like I had an understanding of some of these systems that just felt really natural to me. And I just I fell in love with doing research.

00;13;37;25 - 00;14;01;28
Claire Willing
So I got into some labs as an undergrad and was able to do a bit of research. And then I actually ended up having to take some time off, for financial reasons. And so I worked that year. I think that was really solidifying of my interest to go back and do this. I volunteered in a hospital over that year and was like, I, I just I'm not interested in doing medicine.

00;14;01;28 - 00;14;24;02
Claire Willing
It's not for me. And I just really couldn't wait to get back into some ecology classes. and so when I went back to school, I was just, you know, get into all the ecology classes, got into more ecology research, and I had some really awesome mentors as an undergrad that helped me sort of navigate what it would look like for me to do a PhD.

00;14;24;04 - 00;14;57;28
Claire Willing
Yeah. And so I kind of went down the path and just kept going. but yeah, it was largely to do with the ecosystem, so to speak, around me in college. Yeah. Kind of making those connections, like what you're seeing is what you're learning and it's. Yeah. Forcing. Yeah, yeah. And then having some really important mentors through that process that like help sort of demystify what a PhD was, what it meant to go to grad school, how to do research, like why we do research, all of those things.

00;14;57;28 - 00;15;31;20
Claire Willing
And I think it was a really collaborative group of it was a almost all women, which was, I've learned, actually a pretty unique, system. But there were just this, like, really? It was a really wonderful group of researchers that all collaborated and like, had projects together. And, I think it was really inspiring through grad school. I've had some really great mentors, and I think the, sort of environment that you build in a lab is so essential to being able to do good research.

00;15;31;23 - 00;16;00;21
Claire Willing
So much of the research I do has been like cross pollination from other people coming in from other labs, like I've collaborated so much with a few postdocs who were in my PhD lab and then my postdoc lab. and that's where you get those really exciting ideas is like having having that dialog with people from we all have different backgrounds that we bring to the field, and I think that's really the exciting part of getting to do this work is like pulling all these different pieces together.

00;16;00;21 - 00;16;21;00
Speaker 4
What is it about fungi that's making almost connectedness? Do all of these events and stuff? I live with Celia Luna. They them pronouns, and so I'm currently Claire's lab manager. Yeah, because it's a huge part of the science because, like, we're doing the academic side of it, but then there's a whole other community science side that's like individually funded.

00;16;21;00 - 00;16;42;28
Speaker 4
It does all this work, but it doesn't get like the recognition. Right. and so that working with those local groups and regional individuals that are really dedicated. Yeah. And we need nothing more than that in the climate change. Right. Because it's such a complex and yeah, often sort of seemingly intractable problem. Yeah. So what are some of the things that you're excited about sort of moving forward with your research?

00;16;43;00 - 00;17;25;03
Claire Willing
I think so much of my work kind of moving up to this point has been like, how do we even understand what communities are in these places? Or like maybe starting to understand a little bit about how these communities respond to climate change or different climate change factors? But I think we're at this really exciting juncture right now where we're able to kind of link the information we've been gaining for the past like 15, 20 years about microbial community ecology with things like plant function and plant response to and environmental shifts or plant community response to microbes.

00;17;25;03 - 00;17;58;05
Claire Willing
And so I think it's a really cool time to unpack some of what we've been learning. in a bit more of a applied and functional way. I've also been doing some work with, transcriptomics. And so looking at sort of the acclimation component of microbial communities. And so that's been really exciting too, is getting to kind of use some these new molecular tools are not super new, but like new in my fields to look at how organisms might be able to shift their physiology.

00;17;58;08 - 00;18;17;17
Claire Willing
And I think previously we've been able to do this really well with plants in a lot of ways. But, we really need some of these molecular tools be able to do it with microorganisms. Yeah, yeah. Looking at things like acclimation, for instance, to drought and fungal communities and things like that, like how do fungi shift, which genes are on or off.

00;18;17;17 - 00;18;28;02
Claire Willing
And then how does that kind of translate to how they're physiologically functioning in those environments?

00;18;28;04 - 00;18;50;23
Sarah Smith
And wrapping up our conversation, there is just one question left. What are some of her favorite fungi there? 

00;18;50;25 - 00;19;15;20
Claire Willing
Are these really cool bird's nest lungi that are just the cutest little things. So there produce these. It's almost like a cup. And then it has these spore packets and the spore packets look almost like eggs in the nest type of thing. And then you can do we used to do target practice with them. So you can do like a dropper of water, simulating like a raindrop. And then that's what shoots the spore packet. Oh wow. Yeah. So like just these incredible, incredible diversity of cool ways of growing. Yeah. And then you have some of these, like, super long lived shell fungi that could be there, you know, decades.

00;19;15;23 - 00;19;40;20
Claire Willing
So yeah, it's incredible, incredible diversity. We often think of fungi and like a really kind of narrow view. But actually fungi are part of so many aspects of our lives. and so one of the things that I like to ask students is like, how have you interacted with fungi before? And I think a lot of students don't even realize the ways that fungi might be a part of their life.

00;19;40;20 - 00;20;02;16
Claire Willing
So fungi are essential at the beginning of plant life. They help plants establish and grow. They're also essential decomposers. So if we didn't have fungi, we would just have piles and piles and piles of leaves that would never decompose. So they kind of close the loop. And a lot of the way that we think about, like life on Earth, right?

00;20;02;16 - 00;20;27;00
Claire Willing
It's the beginning of life, the end of life. They kind of are there at all part. And they also are really important in our food systems. So most of our crops are dependent on fungi. There are just so many. If you ever had beer or kombucha, yeast is essential to brewing and baking. And, you know, so many of the ways that we like, consume food.

00;20;27;02 - 00;20;52;10
Claire Willing
Cheese, for instance. Yeah, there's a researcher who is studying this Aspergillus species that creates blue cheese. Yeah. And it's never been shown to reproduce in the wild. So all of our blue cheese has been clonal. so it's like, yeah, there's no reproduction happening. and he was able to figure out that they just needed really specific conditions, like a particular temperature to be able to mate.

00;20;52;10 - 00;21;18;29
Claire Willing
And then he created all these new, like, completely novel blue cheese fungi that create totally different cheeses. And yeah, it was so cool and exploded. The blue cheese industry. Yeah, yeah. He's won all these awards in England. Yeah. For all his new blue cheese is oh my gosh that's incredible. Yeah. As a fan I thank you for our blue cheese.

00;21;19;02 - 00;21;50;20
Sarah Smith
Want to learn more about Claire Willing's research visit our website at environment.uw.edu. A big thank you to our guests today Claire Willing Liv Filialuna and Sarah Minkowski. From all of us at Field Sound, thanks for listening. See you next time.