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| Hi everyone, I’m Bri Price. I’m the WSU Bee Program Extension Coordinator. Thank you so much for being here today, to one of our 2025 webinars. I have just a couple of announcements before today’s speaker. The WSU Honeybees and Pollinators Program is a cornerstone of the College of Agricultural, Human, and Natural Resource Sciences, abbreviated CAHNRS, that’s dedicated to fostering resilient ecosystems in Washington and beyond. Our mission intertwines innovative research, community engagement, and education to safeguard pollinators that are pivotal to our food security and environmental health. In partnership with the CAHNRS Resilient Washington Initiative, we’re committed to advancing sustainable practices and pollinator-friendly landscapes, as well as ensuring a flourishing future for agriculture and natural resources. We have one more upcoming webinar after this one this year. For more information about that and possibly registering for it, if you’re interested, please visit our upcoming events page on our website, bees.wsu.edu. There will be time to answer any questions you have after the presentation today, so feel free to type your questions in the Q&A box below anytime during the presentation. After the event and before you close your browser, you’ll be prompted to answer a short 5-question education outreach survey. Your participation in this really helps us make our education and outreach more tailored to what you are wanting to learn about. Today’s speaker is Taydin Macon. Taydin just passed his preliminary exam, so he’s no longer a PhD student, he’s a PhD candidate in the Hopkins Lab at WSU. Congratulations, Taydin. Taydin has worked on various projects involving honeybee pests and pathogen detection and treatment. This webinar will focus on using an up-and-coming technique known as environmental DNA, eDNA, for detection of honeybee pests and pathogens. The webinar will consist of the history and development of eDNA techniques, the use in entomology and agriculture today, and his own projects involving pest and pathogen detection. You can go ahead and share your screen, Taydin. I will hide my video. | Woman in grey shirt on screen wearing glasses and a Washington State University Logo in the background. |
| Taydin Macon: All right, well, hello everyone, good afternoon, and thank you, Bri, for that, awesome introduction. Like Bri said, my name is Taydin Macon. | The title slide reads “Using eDNA to Assess Colony Health”. An image displays a hand holding a pile of crawling bees. The bottom of the page displays the presenter’s name, date of presentation, and associated research institution (Taydin Macon, September 8th, 2025, Washington State University). |
| I am a PhD candidate now in the Hopkins lab, and I’m co-advised by Dr. Brandon Hopkins and Dr. David Crowder. The projects that I work on involve honeybee health, as well as, some statistical modeling. And before I dive further into my presentation, I’ll just give a little bit more about myself. | This slide has a header saying “But first…” followed by 4 photos in a row. From left to right, the photos depict the following: the research in an almond orchard during almond bloom, a close up of an index finger holding a native bee, the researcher standing in front of a creek holding a frog, and two researchers dressed in beekeeping veils performing honey bee colony surveys on 4 colonies; colonies are opened and one researcher takes notes while the other collects samples of bees. |
| So, I’m originally from a small town in Southern California, just south of Bakersfield. It’s called Tehachapi. | This slide contains 4 images. In no particular order, one is of a map of California, one is of a city limit sign for Tehachapi, California with mountains and snow in the background, another is of mountains in the distance lightly dusted with snow at their peeks, and the last is of a train track making a loop in a hilly terrain. |
| I grew up there, and then when it was time to move on to undergrad, I moved to LA, where I attended Loyola Marymount University. At Loyola Marymount, I got two degrees, one in philosophy and one in physics. And after my time there, I decided to enter the workforce, where I worked at Children’s Hospital Los Angeles as a research coordinator, for two of their different teams. The first team was their blood and bone marrow transplant team, and the second team, focused on children with medical complexities and various research protocols involving them. Then, at the end of 2023, I kind of reflected on where I wanted my life to take me, and I decided I wanted to go ahead and pursue my own research in a new field, and that’s when I decided to reach out to Dr. Brandon Hopkins about joining the Hopkins Lab in the Honey Bee Lab here at WSU, and I’ve been here ever since. Currently, I just started my third year, and as Bri said, I just passed my preliminary exam, so I’m no longer just a PhD student, I’m a PhD candidate, and the rest of my time here will be working on various research projects and trying to get some publications out. | This slide contains 3 images in a row. From left to right, the images depict the following: the researcher standing in front of a chapel wearing a graduation sash and throwing up a graduation cap, a group of 7 individuals wearing dinosaur onesies and kneeling in front of giant play blocks with the letters “C”, “H”, “L”, and “A” on them, and lastly, a row of five WSU graduate students sitting in a diagonal row in a conference room. |
| Now that that introduction of myself is over, let’s go ahead and get cracking into, some… some bee fun. | This slide has the phrase “Let’s get crackin’ into some research” across the bottom, with three gif images in a line. From left to right, the gifs depict the following: a hand lifting a wooden lid to open a honey bee colony, the research lifting one deep from the colony off the other, and the research smoking the opened colony. |
| So, this whole… this whole presentation is going to be on this concept called environmental DNA, or eDNA. So, a… a real, like, what would the name be? Like, academic definition of this would be, any DNA of an organism collected from an environmental sample, such as soil, air, or water. And that just means, all living things are continuously shedding genetic information into the environment they’re in, whether it be, you know, for us humans, it could be our skin cells, it could be our hair. If you’re a fish, the fish could be pooping in the water source it’s in, it could be shedding scales, or whatever, and all this organic material has that organism’s DNA attached to it. And so, the whole concept of environmental DNA is using the presence of that genetic material in the environment to detect a specific species when that species may not be physically present at that specific time and place, but is present overall. And one of the first references, for the use of eDNA actually came from 1987, in a paper titled The Extraction and Purification of Microbial DNA from Sediments. So, this paper, they were just looking at, DNA from microbes inside sediment debris. | This slide is titled “Environmental DNA” (eDNA). There is a description of what eDNA is and a set of images accompanied by arrows. The top image is of a fish underwater. Three arrows point away from this image towards 3 others. One is of a poop emoji, another is of fish scales, and the last is of a question mark. Three arrows are beneath each of their images, pointing away from them and toward a final image of a DNA strand. |
| So that was that was pretty technical. To pull it back a little bit, eDNA is basically, a tool you can use to find a needle in a haystack. So, let’s say if you… if you were trying to find a needle in a haystack, some of the methods you could do to find that needle would be, you could sort the hay out, one piece, one by one piece, individually, and that would take forever. Or you could use a piece of technology that could help you detect the needle way faster. You could use a metal detector. And eDNA is basically like a metal detector for environmental samples. So instead of having to sort out the entire environment or an entire sample from for a specific species, we can use this molecular technique to just detect the DNA of that species. | This slide depicts a needle in a haystack. |
| Now, how are these samples processed? So, I said, whenever you are looking for eDNA, you collect an environmental sample, like, you collect water or dirt, or you can use an air filter. What do you… what do you do after that, once it’s collected? Well, there are various molecular techniques that you can use, and I’m not going to go into too much detail onto these, because that’s kind of nitty-gritty, but basically, you can do something called PCR, which just tells you if the DNA of a specific species is in that sample. You can use qPCR, which is very similar to PCR, but it can help give you an estimate of how much specific DNA is within a sample. And then lastly, you can use this concept called metabarcoding. And metabarcoding is, like, an amped-up version of PCR, where rather than just looking for one specific species in a… or DNA from one specific species in a sample, you can look for DNA from multiple species, or DNA from a whole genus of animals. So it’s more, wide-range. | This slide has the title “How are eDNA samples processed?” The three methods depicted are PCR, qPCR, and metabarcoding. Five images accompany these methods, showing visual representations of DNA multiplying, exponential curves representing qPCR amplification, and DNA within a small vial. |
| When eDNA first came out in ecology, it had traditionally been used heavily within aquatic settings, and one of the first mentions of eDNA within an aquatic setting, was from 2008, where, this group of researchers, they were looking for a specific type of bullfrog. They were testing whether or not this eDNA was possible by looking for a specific bullfrog in different ponds that were known to have different densities of these bullfrogs. So, they looked at 3 ponds that had low density of these bullfrogs, 3 ponds that had high density of these bullfrogs, and then, finally, 3 ponds that there had never been any detection of these bullfrogs before. And what they found out was that in both the low density and high-density ponds, they were able to detect eDNA of those bullfrogs after collecting a water sample, and then from the ponds that there had never been any sightings of these bullfrogs, they did not collect any eDNA. Which was good, it was proof of concept. We know that these bullfrogs are in these locations, we know that they’re not in these locations. Can this eDNA technique be used to detect the bullfrog? Yes. And then they also did some aquarium studies looking at different tadpole densities, but…This paper was very successful and very foundational within the realm of eDNA. | This slide has the title “Environmental DNA in Aquatic Settings” with a description of an early eDNA study. There are also three images: one of a blue nitrile gloved hand holding a clear test tube containing water over a larger natural body of water, a 1.5 milliliter tube containing a clear, cloudy liquid, and another visual representation of DNA multiplying in a PCR assay. |
| So that previous paper that I was talking about was mainly just presence and absence of a species. So, is the DNA of, that bullfrog at this pond, or is it not? The eDNA work has also progressed to try to, do population estimates, so based off of the amount of eDNA in the environment, are we able to estimate how many of a specific population are also in that environment, rather than just saying, yes, at least one individual is there. From this first paper, they saw that potentially the amount of biomass or the amount of, DNA they collected had the potential to, reflect the potential species distribution within a natural setting, basically just saying, as the biomass increased, there’s the potential to also, for it to mean that there’s more of a specific type of organism in that area. And then in this next paper, Sigsgaard et al. 2017, they were able to use eDNA to look at different, shark aggregations. Which is really cool. So, this technology in these other fields, has been really useful in not just saying, yes, these particular species are present, but also it can give us some information about, you know, population sizes, population dynamics. | This slide has the title “Beyond presences/ absence detection” along with 2 descriptions of research studies and 2 images, one of a fish and another of a whale. |
| So… that was in aquatic settings. I’m gonna shift gears to eDNA, and pollinators, and we’ll eventually get our way down to bees, but just in general, talk about, a specific pollinator to show that it’s been used, not just in aquatic settings. One of the coolest papers, I read when I was first diving into this eDNA research was on, this bat. It’s the Mexican long-nosed bat, and this group of researchers. They were trying to understand the different migration routes this bat takes. So, this bat will move from southern United States down to southern Mexico during different times of the year, and as it migrates, it will go and pollinate different agave flowers. And so, this paper, the researchers collected, agave flowers and picked up the eDNA of the bat from the agave flower, and they were able to estimate the… what is called nectar corridors of the of the bat as it migrated. So basically, just the paths that the bats are taking as they migrate. | This slide has the title “eDNA and Pollinators” along with a depiction of a research study and 3 images. One image is of an agave flower, another is a close up of a bat head, and the last is a heat map of the southern United States and Mexico, where red areas represent high environmental suitability for a bat species that pollinates agave flowers. |
| Another example of eDNA and pollinators, this one, was looking at apple orchards, and they were basically trying to understand, the different flower-visiting arthropods that, come to help pollinate these apple orchards, and so they used that concept that I was talking about earlier, called metabarcoding, along with standard methods of detection, which would just be looking at that flower and seeing what, what insects come and land on it, or what other pollinators come and land on it. And they found that, through the molecular analysis, through the eDNA analysis, there were 17 different taxa, or 17 different groups of arthropods that were coming to pollinate these flowers, and 16 of those were non-bee arthropods, and they used that molecular data to help bolster and support the visual data. And I don’t have a specific slide about this, but a lot of the eDNA work that is currently being done within entomology is not using eDNA necessarily to replace standard methods, but is using eDNA to help supplement traditional methods of detection. So, in entomology, if a group of researchers is looking, looking at the biodiversity, insect biodiversity in a specific area, they’ll usually use, various amounts of traps, and then they’ll go and individually ID, specimens from those traps, and these eDNA analyses can help, enrichen the species that are collected from these types of samplings. | This slide is titled “eDNA and Pollinators” and has a description of a study alongside an image of an apple blossom. |
| Alright, so finally, we’re getting into, some more bee-related stuff. So, eDNA within honeybees, specifically within honey. So, a lot of the initial work, within eDNA in bees has been looking at the DNA that is present within honey. As beekeepers know, you know, you have the bees. Collecting nectar and creating honey all throughout the season, and so, it is a potential store for, you know, all the genetic material that is within the hive, and also the genetic material that the bees are picking up from their environment. So, several researchers have been interested in the DNA present within this honey. For example, one paper in 2022, they were… they took some honey samples, I believe this specific, paper that I’m thinking of, they just took honey from the store, and they ran eDNA analyses on this honey, and they were able to tell what subspecies of honeybee helped to make that honey, which is… which is super cool. Similarly, next down, people have been able to look at, not just what subspecies has made the honey that they’re testing, but also the origin of the world that that subspecies came from. And then people have been able to, look at the honey and look at DNA from the varroa mite. And they’ve collected DNA from the varroa mite within honey, and that is really important because they were looking for different types of what are called mitotypes, and that’s just basically a different genetic variants of the varroa mite, and that’s important because if you’re trying to, if you’re trying to target a species, a pest species like the Varroa mite, it’s important that you know exactly, like, what type of roe mite you are trying to kill off from the colony. And then lastly from this slide, some researchers were able to, look at honey that was made from honeydew, which, if you’re not familiar with that, honeydew is honey, or sorry, or honeydew honey is honey that is collected from, well, rather, the source of it is from aphid poop rather than nectar. So, aphids, when they are feeding on plants, they’re processing the sugars from the plant and taking up a lot of the plant fluid very quickly, and because it’s not very nutritionally dense, they’re excreting a lot of what they’re taking up from the plant, and that causes, like, a sticky sap to to be formed. It collects on the leaves, it can collect on your car if you’re parked underneath a tree where there’s a bunch of aphids, and you know, luckily for the bees, the bees can take that source, that sweet, sugary source, and turn it into honey. So, researchers were also able to, determine what aphid species that bees had taken honeydew from. Which is super cool. | This slide is titled “eDNA and bees: Honey.” There is a description of research papers that have used eDNA to investigate honey. There is also an image of honeycomb in a fame and a honey bear bottle on the right side of the screen. |
| Aside from honey, there’s also been eDNA work, with pollen. So one particular study that I’d like to mention, was looking at an invasive plant species in Australia. It’s a type of bone seed, they are trying to eradicate, or at the time they were trying to eradicate, and what they did was they, put colonies in, areas where this bone seed had been known to have been, and they put pollen traps on their colonies, and sure enough, they were able to detect pollen from the bone seed, from the pollen traps once they collect it. So, in that instance, it was really crucial, because, you know, the bees, their foraging distance can, you know, their radius can be 2 to 4 miles, maybe even more if they’re in high-stress environments. And so, rather than having a group of researchers have to go, like, walk up and down that massive area of land. Looking for a species of plant to eradicate. They use this technique to help show them, like, yes, this invasive species is in this area, we need to do something about it. And then lastly, people have used this eDNA technique just for overall pollen analysis, so placing bees in an area during different times of the year and seeing what groups of plants they’re foraging on at different times of the year. And that’s just to have a better understanding of the flora in the area, as the time transitions, and also what the bees are, you know, interested in consuming at the time. So overall, the eDNA work, though it is still within its infancy in entomology, in honeybees, it has been used a good amount, and especially the amount that it has been used for detection of pests and pathogens has also increased. | This slide is titled “eDNA with bees: Pollen”. It depicts studies that have used eDNA to investigate pollen origins. It also has pictures of a yellow flower and a honey bee colony pollen trap on the right side of the screen. |
| As I was saying, eDNA was pests and pathogens. So, again, another use of eDNA within honey. This one study was able to detect DNA from Nosema within honey. Another study was able to detect plutonius, which is the causative agent of European foulbrood, within 87% of the honey samples that they took. And they took these honey samples from 17 different countries, so that study really helps to show, like, the prevalence of this, you know, harmful bacteria that causes European fowl brood, within these honey samples, which implies it is within our colonies as well. There have been studies that have used eDNA to detect small hive beetle within hive debris. Small hive beetle, if you’re not familiar with it, it is a little beetle that feeds on pollen, so it takes away resources from the colony. And then this last paper, really was my first introduction into eDNA, so I wanted to include that. It’s from Broadman et al. 2022, and within this paper, the researchers, I believe they were down in Florida, they were taking various types of samples from colonies. So, they would take, like, a cotton swab and swab, the entrance of their colony, or they would take a frame of comb and wash the comb out, and then filter out the water with a special type of filter, or they would take a water sample from a nearby lake, or a soil sample from underneath the colony. So basically just taking various types of environmental DNA samples, or environmental samples, looking at the DNA from those samples, and they were to… they were able to detect various, the DNA from various pests and pathogens from the variety of different samples. | This slide is titled “eDNA with bees: Disease and Pests” and has brief descriptions of studies that have investigated eDNA for the detection of honey bee pests. It also has two images on the right hand side, one of a close up image of a bee with a varroa mite on it and another of several small hive beetles infesting a frame of brood comb. |
| So, all of that stuff is really cool. It is a very, very promising areas in all of ecology, in entomology, and especially within beekeeping. However, there are some issues, and I just wanted to highlight them real quickly. First off, there are these things called PCR inhibitors. So if you remember, PCR was one of those molecular techniques that we used to process our samples, and basically what a PCR inhibitor means is it’s something that is within your sample that, you know, if the DNA is still in… is in the sample, this inhibitor will prevent the PCR from detecting your DNA. So that’s PCR inhibitors. You can get contamination from your samples, so let’s say I wanted to, sample 3 different sites for 3 different organisms, and Site 1 had that organism present, but I contaminated my gloves got contaminated with the organism’s DNA from Site 1, and I got that DNA into my sample from Site 2, then my site 2 sample could come up positive, even though there might not be that organism, within Site 2, so contamination… contamination can be a big issue. Incomplete sequence libraries, basically that just means, whenever we’re running these molecular techniques, to detect the DNA, we have to know the way that the DNA looks, or the way that the DNA is built in order to detect it, and…this third bullet point just means that we don’t know the way that all of the DNA for… of all the species, all the organisms of interest is built, and if we don’t know how it’s built, we can’t detect it. Fourth, there’s an unclear relationship between eDNA concentration and species abundance, so even though there have been studies that have shown relationships between the amount of species in an environment and the amount of DNA within that environment, it’s still not a clear-cut, it’s still not clear-cut, and that’s because different organisms have different, shedding rates, like DNA shedding rates based off of their age, based off of time of year, and then also, DNA does not just hang out in the environment forever, indefinitely. It degrades, so it’ll break down, and as it breaks down, it gets harder and harder to detect, and it can break down from things like, temperature or radiation from the sun, or you can have, small little microbes, that come and eat the DNA, or just other environmental conditions, like, rain washing DNA off of a plant leaf, if you’re interested in, pollinators that visit a specific plant species. So, there are lots of problems as well as benefits, but there are… there’s a lot of research going into it right now, to try to overcome those problems. | This slide is titled “Problems with eDNA” and lists out multiple issues scientists have with eDNA studies. |
| Oops, sorry, my cat just ran across my screen. So, why use eDNA for species detection over standard methods? I would say do not use it over standard methods, but use it as a supplementation to your standard methods, as a better way of understanding, what you’re looking for. | This slide only reads “Why use eDNA for species detection over standard methods?” |
| So this is going to get into some of the research that I have done, but I’ll use the example of, European foul brood, which is caused by the bacteria Melissococcus plutonius. If you’re unfamiliar with European foul brood, it is an infection that primarily affects the larvae within a colony, and it causes them to get really sickly. So, you know, when you’re beekeeping and you’re looking at your immatures, your uncapped brood, you really want to see a nice, plump, white larvae in each cell. And what the European foul brood does is, it causes those larvae, those larvae to shrink and deflate. They go from a nice milky white color to a brown color, and eventually, if they do die, which a lot of them do, it’ll turn into, like snotty, gooey mess in the frame. And so I’m saying all these, like, physical symptoms of European foul brood, of the presence of Melissococcus plutonius right now, but, what is tricky is that this bacterial disease does not always present with these symptoms. | This slide is titled “Melissococcus Plutonius: Causative Agent of EFB” and has a description of the bacteria along with two images on the left side of the screen. These images depict sickly looking larvae in brood comb and microscopic images of bacterial cells. |
| You could have a colony that has the bacteria present in it, has an active infection going on, but may not be, may not be displaying signs of European foulbrood. And so, this would be an instance where doing some sort of eDNA investigation within the colony, would be of interest, because even though, as I was saying, there may not be physical signs or symptoms of the disease, the DNA of that bacteria, that bacteria itself, could still be present, and we could still detect it. | This slide contains 4 images with arrows. The first image depicts a nurse bee feeding a bee larva. The nurse bee has a cartoon image of a bacterial cell on its abdomen, indicating that it is infected with the bacteria. Below this image, an arrow points to another image of just the larva, now with the same cartoon bacterial cell on it. This represents transferer of the bacteria from nurse to larva. Next, another arrow points from the larval image to a diagram of a bee gut, where we can once again see a cartoon image of the bacterial cell in the section of the gut that it colonizes. Lastly, two arrows lead away from this diagram: one leads back to the original image of the bacteria carrying nurse bee while the other leads to an image of a bee larva getting turned into brown goo and pulled out of the cell. This represents the larva either dying from the bacteria or reaching adulthood and transferring the bacteria back to other larvae. |
| Some ways that people can treat for European foul brood, you can do a brood break by caging your queen, because if there’s no brood, there’s no, immatures to transmit the bacteria to. You could re-queen, there’s some papers saying… and, like, talk about re-queening, helping to reduce symptoms of European foul brood, or you can just wait it out, because oftentimes it’s said to be an opportunistic disease. Occurring in times of, like, resource dearth, so in early spring when there’s not a lot of nectar for the… for the bees to forage on. And then you could also, use oxytetracycline. Which is a treatment for the bacteria. | This slide has the header “Treatment” on it and lists several methods people use to treat for European foulbrood. There are also images of a caged honey bee queen in the top right, a honey bee on a flower just below, and a product label for oxytetracycline in the bottom left. |
| So, again, I kind of jumped out of order in my head, my apologies, but this is a problem, and eDNA could be a solution for this, because you can have these colonies that are diseased, but are asymptomatic, and could transmit the disease to other colonies. That’s just based off of different lineages of the… of the bacteria that exist. And then it’s also a problem because there is an association with… or there is a potential association between, increased incidence of European foul brood and different pollination events, for example, blueberries. People, there’s mixed literature about, colonies going to blueberries and getting more European foul brood compared to colonies that, don’t go to blueberries, so it’s kind of mixed, but it definitely is a problem. | This slide is titled “Why is this a problem?” and lists why European foulbrood is concerning for beekeepers. It also has a diagram of a sodium and potassium ion exchange occurring at a cell wall. |
| So, the bulk of my eDNA work, or not the bulk, the beginning of my eDNA work, was with European foulbrood, and it started off with this, as a subset of this multi-center project, where these four groups, we’re trying to understand, the relationship between European foul brood incidents and blueberry pollination. And some things that they were interested in were, like, the pollination event, does weather have an influence, does the time of year have an influence, does the geographic location have an influence, nutrition, etc. Just basically, what causes European foulbrood. | This slide contains a list of question regarding European foulbrood. It also contains four logos of universities studying its incidence. From top left to right in a clockwise motion, the logos are of the following schools: Mississippi State University, Washington State University, UC Davis, and Oregon State University. |
| And so, with my interest in eDNA, I was able to, I was able to apply some of these eDNA techniques while we were doing these studies. So, this study consisted originally of around 1,500 colonies. They started off in California for almond pollination, and then they moved around, the United States during their different pollination routes for the year. Well, I guess this occurred over 2 years. Half of them on that route, they’d go to blueberries, and the other half didn’t go to blueberries. | This slide contains a follow diagram and descriptions of the movement of colonies during a research project to investigate European foulbrood incidence throughout the pollination year. The study starts out with 1536 colonies that all pollinate almonds. From there, half of them will go to blueberries while the other half go to a different crop. Then all the colonies will be lumped back together and go to either a specialty crop or holding yard for the rest of the year. The study will then repeat itself in a second year. |
| And so what I did, for one of my first eDNA projects, I was curious if we could detect, the eDNA of European fowl brood on hive tools. So after blueberry pollination, 2 years ago. All of the… we had colonies that had gone to, that had gone to blueberries, and colonies that had not gone to blueberries, and within those mixes, we had colonies that had, severe cases of European foul brood infection, and then colonies that had moderate, or no infection, and what I did was, after going through a colony, and after we graded it, either, like, a 0 through 3 for European foul brood infection, I wiped down that hive tool, to get any eDNA off of the hive tool, hopefully trying to… trying to get DNA of the causative agent of European fowl brood, Melissococcus plutonius. I wiped down 10 hive tools from each of the different infection levels. And then I performed, that molecular technique called qPCR on these, 40 different hive tool wipe samples, and what I was able to find was that on all of the samples, I detected the Melissococcus plutonius, DNA. And what was really interesting about this, is when it comes to sanitization practices. So, there is somewhat of a concern that us as beekeepers, when we are beekeeping, we could, if we’re not sanitizing our tools, our equipment that we’re using, we could potentially be, transmitting disease from colony to colony as we, you know, crack open one hive, move the frames around, and then move on to the next hive, crack it open, etc. We could potentially be inoculating colonies with these types of bacterial diseases. And although this does not say, you know, the results of, this, these molecular analysis is not saying that that is what is happening, it is, evidence to suggest, you know, further research within this field. So this eDNA, the way that I, collected these samples, I could not tell if it was, living or dead bacteria from the samples that I was collecting, but nevertheless, it was DNA from the bacteria. Also, with these samples, I had tried to see if there was a relationship between the quantity of eDNA I was detecting on the samples, and the severity of infection that we had graded the colony that the sample had come from. And unfortunately, the results of that analysis were inconclusive, so I didn’t include that. | This slide has the title “eDNA and EFB Wipes” and contains 4 images of hive tools across the screen, each with a different infection level going from lowest (no signs of infection) to highest (severe infection). Additionally, the top of the screen has an image of a hive tool scrapping wax from a frame of comb. |
| But that was my first, big eDNA project that I worked on. And that kind of pushed me, or I guess that kind of pushed me also into looking into, other potential sources of, Melissococcus plutonius, you know, if the bees could be picking it up from, could be picking it up from other places in the environment, like soil and water. | This slide only has the title “Investigating Crop Soil and Nearby Water Sources for Melissococcus plutonius During Different Pollination Events.” |
| So, the reason why I thought of this was because Brandon and I had come across this paper, where these researchers were looking at, diff… like, nematode species within soil, and they did that, that molecular technique called metabarcoding, and one of the bacteria types that they came up with was Melissococcus plutonius. So I was curious, could, this Melissococcus plutonius be living in the soil that, we are, You know, that our colonies are resting on when they’re going to pollinate these different crops, or these colonies are resting on when they’re sitting in these different holding yards. | This slide has a screen shot of a research paper titled “Bacterial communities associated with Zeldia punctata, a bacterivorous soil-borne nematode.” Additionally, three images sit below this. On the left, one image depicts a field of blueberry bushes. On the right, a microscope image of bacteria overlays an image of soil. Connecting the two images are two angled lines, indicating as if the soil and bacteria image is a close up of the blueberry field. |
| So this was also at the same time as that multi-center EFB project, so I was able to collect, soil and water samples from all across Washington, from the Central Valley in California, and then also a location in Central Montana. | This slide is a graphic of the United States. Each state is denoted by a different color, and California, Washington, and Montana all have green stars in their centers. |
| As I was saying, I collect water, I collected water samples from, mostly just ponds or puddles that I was finding off the side of the road, or just anywhere near these colonies. This water, when I took these photos, or specifically the one in the middle, that was in almonds, almond pollination, and that’s the rainy season for California, so there’s plenty of water everywhere. And then I was also collecting soil core samples from around, these colonies. I did some PCR on it. | The top of this slide contains three images in a row. From left to right, the first image depicts an eDNA water filter collecting a sample from a puddle. The second image depicts a group of scientists collecting samples from a pallet of 4 honey bee colonies. Next to the scientists, there is a large puddle. In the final image, a hand holds a soil core extractor with grass in the background. Below these images are two text boxes. To the left, the text box has information on how the water eDNA sample was collected. To the right, the text box has information of how the soil cores were collected. Below that is a description of how the qPCR assay for these samples was run. |
| And from my PCR, I was able to, come up with positive hits for, the Melissococcus plutonius DNA. So again, when I came up with these positive hits, I was really unsure, like, I don’t know if this is living, if this is living DNA, or if this is bacteria from rather. This is DNA from living bacteria, or DNA from, you know, dead bacteria, just random DNA floating around, because it’s in the environment. | This slide has two identical sections of the United States containing California, Washington, and Montana. On each of them, colored dots indicate locations where water and soil samples tested positive for European foulbrood. In-between the maps lists a question of what crops positive samples came from. Below are specifics of how many samples tested up positive. Below that are three additional images. From left to right: an image of an almond orchard in bloom, an image of blueberry bushes, and an image of flat grasslands with deer in the background. |
| And so, I used this other type of technique, called PMAPCR, and it helps to distinguish between whether or not the DNA you find is from a living organism or a dead organism, and what I found that… after doing that, I found that all of the samples that had come up positive had not been from living DNA. It had been from, or DNA from a living organism. It had come from DNA that was not from a living organism, so I could not conclusively say that, the bacteria Melissococcus plutonius was living and could, living in these environmental samples and could transmit from the environmental sample to a colony that way, but it was still a really interesting, a really interesting, you know, little experiment that I conducted, and it was my first introduction into molecular techniques, and it was a great time. | This slide has the title “PMA PCR.” There are several images on it. From top left to bottom right: an image of a hand holding a soil core, and image of a sonicator bath, a diagram of how PMA works. Below the image of the PMA description is a downward facing arrow pointing to the words “DNA extraction.” Another arrow points away from “DNA extraction and towards “PCR.” |
| The last two studies, eDNA studies that I’ll talk about that I did, are a little bit smaller scale. So this first one, I was interested in, detecting small hive beetle. I was interested in seeing if I could detect small hive beetle, using eDNA, what I did, well, not just detect it, but also, I was interested in if the quantity of eDNA, I could detect related to the quantity of small hive beetles I put within different cages. And so, I made 3 different types of cages, I had a cage, or cages that had 2 larvae, small hive beetle larvae, I had cages that had 4 small hive beetle larvae, and cages that had 8 small hive beetle larvae. And I had 3 replicates of each. These cages, were incubated for 3 days, and the larvae had some pollen patties they could feed on during those 3 days. And then after the 3 days were up, I removed the pollen patty, I removed the larvae, and then I wiped down the cages, with just an ethanol wipe, and then did some DNA extractions on those ethanol wipes. And I found kind of a trend in the relationship between, the amount of larvae and the amount of eDNA, so on this graph, I have 2, 4, and 8, that’s the number of larvae, and then on the y-axis here, that stands for log concentration, that just means how much DNA is in the sample, and there is sort of a relationship, but there wasn’t, you know, nothing was standing out like crazy, nothing statistically significant came out. So, it was… it was both a success and a failure. Yes, I was able to detect the DNA, but no, I wasn’t able to come up with results that warranted the further investigation and using this technique to quantify small hive beetle larvae, at least for myself, because I didn’t have funding, so, that was this first experiment. | This slide has the title “Small Hive Beetle Cage Experiment.” On the left are an image of a small hive beetle and a separate image of small hive beetle larvae on a frame of comb. Next to this, there are three images of plastic cups, each with a text box stating how many small hive beetle larvae were placed into them. To the right of this is a graph of results of the experiment. |
| And then I repeated this experiment, with Varroa. So, really interested in varroa, as we all know, or if you’re… if you’re unfamiliar with honeybees. Varroa destructor is a parasitic mite that, basically ravages colonies and has done so since, the 80s. If they left… if they go left untreated, it can transmit various diseases, and their, you know, their populations, if they go unchecked, will just explode within a colony. So, what I did, I put 10 bees. in a single cage, and then I had cages where I then placed, 5 Varroa mites, cages where I then placed 10 Varroa mites and cages where I then placed 20 Varroa mites, and I had 3 replicates of each. And I did the same sort of analysis, where I have, you know, I was trying to look at the relationship between the number of mites in each cage and, the amount of DNA within those cages that I, you know, collected after an incubation period of 3 days, and I found sort of a relationship, but again, not enough to continue justifying, more research, time, and effort, in these areas. So, overall, this sort of concludes the work that I’ve done on eDNA myself. And just as, like, some final remarks. I think this eDNA work is very promising, and I think It is also costly, But Taydin Macon: Nevertheless, I think that the benefits could outweigh the costs once more of these, like, protocols start to get better, you know, as we get better at detecting these species and get better understanding of how we can use these eDNA to, these eDNA techniques to detect quantities of species. | This slide has the title “Varroa.” On the left there are three images of plastic cups, each with a text box stating how many varroa mites were placed into them. Next to this, there is an image of a varroa mite. To the right of this is a graph of results of the experiment. |
| And so, that concludes my presentation. I’d like to say a quick thank you to, this group of people specifically. This is just a small number of people, that had helped me out. While I was conducting this eDNA research, so I’m super grateful for them. | This slide has head shots of 7 researches that helped the presenting graduate student these experiments. |
| And so, that concludes my presentation. I’d like to say a quick thank you to, this group of people specifically. This is just a small number of people, that had helped me out. While I was conducting this eDNA research, so I’m super grateful for them. And then lastly, I’d like to say thank you to, Washington State Beekeepers Association, or WASBA. They have sponsored my research for two years in a row. I’m so grateful. I’ve been to a couple events of WASBAs, and every time I get to interact with the beekeepers that are part of it, I’m just, you know… I get more enthusiastic about bees. It’s a great time, and it’s a great community, so just wanted to say a big thank you to them, and a thank you to all of you that came here to listen to my research, and thanks to Bri. Bri: Great job, Taydin. If anyone has any questions, go ahead and type it in the Q&A box. You already got a compliment in the, in the chat, Taydin. This is one of the most interesting and informative presentations I’ve seen in the recent past. Very sweet of you. Taydin: Thank you. Bri: I’ll give you all some time to type your questions. Okay, it doesn’t look like any questions are coming in, so – oh, here we have one. Okay, question, does each subject to be tested have to be learned by the PCR machine? Taydin: So, that’s a good question, so not learned by the PCR machine, but you basically… you tell the PCR machine what type of DNA you’re looking for. So, we as researchers, we have to know, the construction of the DNA that we’re looking for, and that’s based off of the different building blocks of the DNA. So we have to know the right order of those building blocks, and then we basically tell the PCR machine, look for this order of building blocks, and then the PCR machine will do that. And all that’s done through, through, like, it’s not something… it’s not, like, electronic, it’s not like typing in the PCR machine, it’s… it’s putting in basically little fragments of… of what we call primers, which are just… it’s like a locking key mechanism. The primers, they fit into the DNA that you’re looking for, so we have to… we have to put in specific primers. And if that didn’t make sense, let me know and I can try to explain it in a different way. That person did reply and said, great, great answer, thank you. You got another compliment as, thank you, great presentation. Are there any other questions in the audience? If not, I’m sure Taydin would love, any emails from you if you have… if you think of some questions later on. Oh, we have another one here. Do you think this technology can be available to the commercial beekeepers at some point in the future? Taydin: I think, yes, I think it could be available to commercial beekeepers in the future. I would say an example… so I would say it’s actually currently being used already. An example of that would be the APHIS sampling, so looking for Tropilaelaps. That would be an example of, and, you know, that’s not just specific to commercial beekeepers, but that would be an example of these eDNA techniques being used within beekeeping. But as far as, like, specifically for commercial beekeeping, I could see how this could have, you know, huge benefits for commercial beekeeping. There just needs to be a lot more research to make it logistically sound for commercial beekeeping, just because, you have so many colonies, and a lot of the beekeeping is, like done quickly, so it’s, you know, have to work through some kinks in order to move it onto that level, but I would say, yes, it could definitely be used within commercial beekeeping in the near future. Bri Price: Alright, that person said thank you, and I’m not seeing any other questions. So I will wrap it up here. Thank you all for attending today. Remember, before you close your browser, you’ll be prompted for that short 5-question education outreach survey. And as a reminder, we do have one more webinar this year. The next one is about using entomopathogenic fungi for varroa control, and so you can register for that on our website, bees.wsu.edu. Also, all of these webinars are recorded and posted to our YouTube channel, so if you have a friend that you want to recommend this to, they can find it on our YouTube channel @wsubeeprogram. So, thank you all so much, and I hope you all have a great rest of your Monday. Taydin: Yeah, thank you. | This slide contains the logo for the Washington State Beekeepers Association. |