Norroa: A New RNAi Approach to Varroa Control

0:01 Welcome to Beekeeping Today Podcast Shorts, your quick dive into the latest buzz in beekeeping. In 20 minutes or less, we'll bring you one important story, keeping you informed and up to date. No fluff, no fillers. just the news you need. Brought to you by BetterBee, your partners in better beekeeping. Hey everyone, welcome to this Beekeeping Today short on Varroa treatments. This is a multi-part series covering the different treatment options available to combat this honey bee pest. Each short in the series will cover one specific treatment option. For the series, we've invited Dr. David Peck from Betterbee to join us. In this short, we will be discussing GreenLight Biosciences Norroa.

0:43 Hey Becky. Hey David. Hey, good to be back. Yeah, we're back together again. More variable control. This is exciting. It's really good. So this is a new approach to Varroa treatment. Everything else has been some sort of mechanical, chemical, organic or synthetic. This is a little bit different. This is a radically different approach. And before we even get into how it works, I would like to just congratulate the manufacturers for Finding a way to name this product something that doesn't have the letters var or apy or anything like that in it. It's called Norroa. It stands for Novaroa. It's easy to understand and it's not like all of the other names of everything else.

1:27 So that makes our lives a heck of a lot easier. And I will say along those lines. We did talk to Adam Packel from GreenLight Biosciences last October, and I believe that's episode three fifty-seven about the development of this product. But today we're going to talk about the actual use of the product. What is it? How does it work? Sounds like a good question, David. Do you want me to answer please? Okay. So so Norroa, as it's delivered to the the bees in this current form, is it's a pouch of sugar syrup and inside of that sugar syrup you've got this active ingredient. The active ingredient is actually a molecule called vadescana, but what it is a piece of engineered genetic material.

2:11 That when the mites are exposed to it and it gets into the mites' bodies goes and basically kind of hijacks the mite's own cellular machinery and interrupts the mite's ability to reproduce, to lay eggs And so it's a it's a radical departure from organic acids and you know synthetic miticides that might just bind to some receptor and you know make the mites fall down or get paralyzed or something like that. This is a totally, totally different approach where they've got this piece of genetic material, it gets into the mites' bodies, and then the The mites are not killed by it, but they are not able to reproduce any longer. And so it stops mite population growth.

2:52 And then as those mites die by attrition, your mite population goes down. That is quite radical. And then it targets only the female mites. That's correct. Because the first stage of any mite reproductive process is the female foundress mite, the mite that first goes into that brood cell and gets ready to start reproducing. She lays an egg that grows into a male and then eggs that grow into females. Well, she's not laying any eggs when she's consumed or been exposed to rather the Norroa product. And so the real clever trick of it is that they've mixed it in with the sugar syrup, and the sugar syrup gets incorporated by the bees into the brood food that the larva is eating. So this molecule when it gets into a bee's body, uh a larva's body, absolutely no effect.

3:38 Just like all of the DNA in every piece of pollen that they eat or any other, you know, incidental DNA that they might consume just doesn't have any effect on their bodies, because they're not Varroa mites. But the mites go and they hide in some of that brood food down at the bottom of the cell as that larva is getting ready to finish developing. take its last few bites of food, and then, you know, spin its cocoon, get capped over, and start pupating. And so the mites, as they're hiding in this food, they're absorbing little bits of this engineered molecule. And that's going in and that's actually changing their ability to reproduce. It's limiting or eliminating their ability to reproduce. So David, they can't reproduce, but can they still feed?

4:20 They absolutely can still feed because it doesn't kill the mites. It doesn't hurt them, you know, in any in any way other than turning off this one molecule that they need to lay eggs. And so they wind up, you know, still in the cell, but but Surely if you were a developing baby bee and you could choose between being fed on by one mite or five mites, you would you would choose the one. And then gradually, as she isn't replaced in the population with any new daughters, and then eventually that that treated mite dies, you're going to wind up with fewer mites. David, can we get a little bit more information as far as how Norroa works as far as with the mites and inside the mites?

5:01 I was hoping you wouldn't ask. Um So so yeah, once the mites in the brood food are exposed to the the active ingredient, the molecule, this RNAi technology, really is based on the idea that you've got an RNA molecule, a double stranded RNA molecule, which is just a little piece of genetic material. This is a very particular piece that has been created and engineered in the lab, but it's very much like any other thing that's found in any fruit or vegetable or piece of meat that you've ever eaten in your life. There's DNA and RNA in there, and so this is just another piece of it. Well this particular piece has a little trick up its sleeve.

5:41 When it gets into the mite's body, it floats around, it gets into the mite's cells themselves. And then the cells say, hey, you don't belong here, you're not supposed to be here. And so they send proteins that go and sort of start chopping it up and saying, You're not supposed to be here. Get out of here, you weird outside thing. Well, that's just what the molecule wants, because it turns out when it's just floating around, it's it's not really doing anything. It's sort of inert. But when the cell starts chopping it up, it suddenly creates little pieces. And one of those little pieces has its own little trick Its trick is that it floats around inside of the cell and it finds some of the cell's very own RNA, some some piece of genetic material whose job is to move inside the cell and cause it to make eggshell proteins, in the case of these Varroa mites, right?

6:30 Something that's important for developing that mite eggshell. And so this this chopped up piece of the active ingredient is going to float over to that thing and say, Hey buddy, and give it a great big hug. Well the problem is the cell has still got these these bouncers inside that are gonna go in and say, hey, you're not supposed to be here. And so they're gonna they're gonna start taking pieces of the the good molecule that's supposed to be there to go create the mite's very own protein and say, hey, you've been marked as an as an enemy and we're gonna chop you up. You're not supposed to be here. You're done with us. We're not gonna make whatever protein you told us to make And so by doing that, it's essentially causing this piece of RNA to go in and interfere with the normal function of the mites cell's machinery.

7:17 And so that's why we call it RNAi or RNA interference. It goes and interferes in that normal molecular signaling pathway So the nice thing as a beekeeper is that I need to know how to take a sticker off of a pouch and put it on a hive. I don't need to know any of that. But for those that are curious, that's what's going on. And it's not anything particularly remarkable. This is a technology that's been, you know, studied for a long time and used in other ways. It's simply getting a molecule into the mite's cell that's suddenly going to take off its mask and reveal itself to be a double agent working for the beekeeper instead of for the Varroa mite. David, how long do female Roa mites live?

8:00 What a great question. Um and I know a lot of brilliant scientists who've spent many, many years trying to answer that question, and the best answer that I can give you is just sort of a shrug. because we don't really know. There's been modeling work, there's been experimental work. It's pretty difficult to track the life of a teeny little you know, creepy crawly inside of an active bee colony, even if you have a glass-walled observation hive, even if you paint your varroomites or put teeny little numbers on them. It's really hard to figure out, you know, when did this mite go into a cell, which cell is she in? When did that bee uncap? You know, is the mite still alive or has she been killed? And so the best estimates we get is that during the Summer, the mites are maybe living somewhere in the neighborhood of of one to two months under ideal conditions.

8:49 I think a lot of mites live a lot less time than that. And we obviously know that mites can live longer because a mite that is hanging out on the bees in the fall is still, some of them are going to be alive in the spring. That's why we need to do winter and spring treatments for Varroa. And so we don't know exactly how long that mite is going to last, but we do know that that she's not going to have any offspring if she has been treated with this compound. So this is a very powerful tool, but it might make sense to knock down any kind of mite population prior to putting it into your colony. Well, that's one way to look at it, right? So th this is not a knockdown treatment.

9:31 This is not something that's going to make your mite population plummet, because of course the mites, even the ones that get directly treated, don't die. They just don't have any daughters So one perspective is I should do a knockdown, then I should put this product in and do my sort of hold down treatment afterwards. Take the remaining mites and limit them even more. I think the the danger there is You know, that makes people often start to think, well, you know, it's the beginning of my beekeeping season, it's springtime, now I can go out, I'll do my first treatment. And, you know, Becky said that had to be a knockdown before I could put my Norroa in And I don't know that's true, because if you are doing winter management, something like an oxalic acid treatment or something like it, that can knock your mites down months before you put the Norroa in in the spring.

10:17 The other thing to keep in mind is that the time of year that you put Norroa into your hives is really, really, really, really important. And there are times of year when it's a great choice, and there are times of year when it's just not a good choice. And so you want to make sure that you're not sort of hamstringing yourself by trying to do one manipulate one treatment and then a different treatment, if that's going to get in the way of putting the Norroa in at its most effective time. And the reason for that is baked right into how it works, right? Most of the miticides we've talked about, we've said, these work great. They work so much better when you've got no brood in the colony. These work excellent, but they're not as effective because they don't penetrate the brood caps, right?

10:58 Many, many of the miticides we've had to give that caveat. In the case of Norroa It doesn't work if there is no open brood in the colony. If there's no place where brood food is getting mixed up Fed to larvae, and then mites are running in and sort of snorkeling in that brood food, they're not going to get exposed. And so it's not going to be effective. And so it's uh it sort of turns on its head that idea that mite control is easiest when there's no brood So in the in the sort of ideal scenario, I think for most people's nectar flows, what you're going to be looking at is after that sort of initial Spring startup when your colony is gobbling up all the nectar they can get so that they can start raising brood, you might be able to put in something like a single Norroa treatment or two pouches one after the other, which is allowed by the label.

11:47 And then knock your mite levels, not knock your mite levels down, but hold your mite levels down, hold them steady, interrupt mite reproduction so you don't see that big buildup of the mite population over the course of the spring and then subsequently the summer. We've talked a little bit about the delivery of Norroa. Can you describe that process? Because I've heard a couple different approaches to uh delivering it. On the label, very explicitly, it gives you two different ways to do it. It is these pouches of sugar syrup that have the vadescana, the active ingredient, the genetic molecule inside of it. And so you you if you've got a single deep colony. You take those two pouches of sugar syrup, they've got little holes already pre-poked into them, and then you peel off the sticker that's covering the holes, set it down on top of the top bars, the bees go up and they can eat it.

12:32 I believe there's nothing that prevents you from mixing it into a an existing feeder, although I think generally folks are finding it's easiest to have it in its own bag. and then apply it that way. If you've got a double deep colony, then probably you're not going to be putting it down, you know, on top of the bottom brood box, putting a shim around it to to let these pouches occupy that space then putting the second box, then putting yet another shim and more pouches. So if you've got a double deep colony, you would probably just put four pouches on top of the hive. and you know treat the entire brood nest from the top that way. So that's the two pouches all at once treatment. There's also a one pouch followed by a second pouch treatment per brood box.

13:16 And so in that case, for a single deep box, you're putting one pouch in, and then the product descrip or the uh product label makes very clear that as long as you put a second pouch on any time within one to three weeks after the first one has been put on, that can be put into the into the colony again on top of the brood box. And it's basically going to stretch out the time when this molecule is getting put into brood food. It's going to increase the number of mites that are going to be exposed to it. And I've heard that there's an option of placing the pouch on the bottom board. Yes, you can put it onto the bottom board if there's space in between your bottom board and the bottoms of your frames. So not every bottom board can accommodate it, but if yours does and if you're willing to lift the whole colony off of it to get the stuff in there or stuff it down through the entrance.

14:03 Yeah, the bees can take the syrup either from the top or the bottom. You know, personally I would probably put it on top. That's where I typically put my sugar syrup. David, we've been telling beekeepers to monitor for mites and then do an intervention with some kind of control if necessary and then monitor again so that you know that your treatment or your control has worked. So with the fact that you're not getting any kind of immediate might death from this treatment. How do beekeepers know that this works? Yeah. It's completely unlike other miticides where I can put a screened bottom board underneath my hive, do a treatment, and then go out a few days later and most of the time find a substantial number of dead mites.

14:49 I'm not going to see that. So it is more difficult for the beekeeper to assess, and that's one of the places where you need to rely on Research. You can rely on the research from the company. Obviously they've they're spending a lot of time doing it. But what's more important is getting research from trusted third parties, right? From a university lab, from uh beekeeper who knows what they're doing from groups of beekeepers who are able to evaluate this product and can report based on really being systematic about putting it in Seeing how their mite levels change or don't change over the course of the season and then reporting that out will start to give us clear information about when an application was a good idea and when an application maybe wasn't as effective or wasn't it probably the right tool to have reached for.

15:35 And I'm still concerned because if there was a high mite population going in and those mites are transferring viruses and that treatment was used, even though the mite reproduction was suppressed, you could still have virus transfer and then that could impact colony health. You're right. You could watch a colony die after being treated with Norroa and Think, oh, this colony has died because the mites transmitted viruses, the viruses killed the bees. You could do laboratory tests that confirmed all of that And it might lead you to believe that the Norroa wasn't working, but really it just means that you didn't use the tool the correct way. You went to a colony that was maybe already a goner, already on the way of dying from mites and high levels of virus And the Norroa was only doing its job, which is stopping mite reproduction and then slowly causing the mite population to drop.

16:30 It's not something that you want to reach for if your mite population is sky high. It's something that you grab when you think you've got the mites under control and you want to keep them under control for a longer period of time. And it doesn't sound like it's much of a fall treatment either. Well, it can be. So we should talk a just a little bit more about the r the sort of rules and recommendations for putting it into the hive. Norroa is a product that works when the bees take the sugar syrup with the active ingredient out of the pouch and then they incorporate that into brood food. So if your colony is not actively rearing brood, useless, not going to help you. If your colony is in the middle of a dearth and therefore are so desperate for food that they might just eat all of the sugar syrup in the pouch to keep all of the adult bees alive, they might very well be cannibalizing brood to try to survive Obviously, it's not going to do its job.

17:21 It's not going to work. If your colony is experiencing a really dramatic nectar flow, if you've got honey coming in, you've got huge amounts of nectar floating around in that hive. and it's diluting all of the Norroa, then it's also not going to be able to to get enough of the stuff into the mites' bodies that it will have the right effect. And so what you need to do is find a period of time when your colony is neither in a dearth nor in a honey flow And for a lot of beekeepers, that's not that hard, right? They know they've got this flow, that flow, long periods of dearth in between. But for plenty of other beekeepers, that it's sort of an insane statement, right? When is my colony neither in a dearth nor in a flow? And so that's probably gonna wind up being sort of place by place, season by season, as people get more familiar with the product, learning Uh this you know the spring's a little earlier this year and so I want to make sure that I get my Norroa in a little bit sooner or maybe a little bit a little bit later.

18:18 If you've got a period where you've got a lot of of sort of trickles of nectar coming in, it's probably gonna work just fine. And that's true for a lot of people in the spring. If you've got an absolutely booming gangbusters, tremendous spring flow If you're out there and you can't hardly get to your bees through for the snow, and then suddenly all the snow melts and all the maple trees bloom, and you've got this huge amount of maple nectar coming in and supers on the hives. That's probably not the right time for Norroa, right? You either should have gotten it in a little bit sooner, or you're gonna need to wait until after that flow and then find a spot to put it in. But It's not as hard as it seems. You just have to understand that what you're looking for is no super big nectar flow, no really, really, really fierce dearth.

19:04 And you've got to have open brood in the hive so that the bees can use it. I could put gallons and gallons of this stuff into a hive in December, but if my bees aren't rearing any open brood, the mites are never gonna encounter it This becomes very important because it's not a cheap product to use. Right. That is certainly true. That the the product is generally sold by the pair of pouches, and it's two pouches per brood box. And so you wind up paying a good deal of money for this innovative new treatment. And so it's not the cheapest mite aside by any stretch, and it probably won't be for a very long time, if ever, because it's uh it's a pretty high-tech way of trying to target Varroa mites But yeah, be a beekeeper needs to be aware that if they're looking at this or listening to this short and thinking, oh, I'll just put this into my hive four times a year, well, double check how much you're selling your honey for before you think you can you can turn a profit on your hives doing that.

20:00 I would like to say though if you are a newer beekeeper and you're starting with a nuc or a package that might be easier to time the application of Norroa because it's not like you came through the winter with huge honey stores and you're trying to make sure that they're going to use it for the right thing. But If your colony is building, then there might be a sweet spot where you can be pretty confident that Norroa is going to go into the brood food instead of Yeah, I think that's a great point. A package at a certain point, because it's broodless when it's installed, it gives you so many opportunities for mite control. I don't know that I would want to to add in the expense of a Norroa treatment right then.

20:42 But for a nuc, I think it's an even better choice, right? I'm not putting supers on my nuc, even if I've got uh maple nectar coming in. I can I can work that nuc and grow it up into its hive, have them be building comb which is gonna gobble up some of the incoming natural nectar. And if I time it right so that I can get them to take that syrup, incorporate it in the brood food and then take what I know is my whatever it is, my starting population of mites, and keep that from growing and even watch it drop over time, I think I could probably as a new beekeeper have a very, very easy first year. I will also say if you're a beekeeper in, for example, the Twin Cities area, your package, even if you use an oxalic treatment because there we just have a lot of bees and a lot of wintered colonies.

21:28 Your package will need intervention by late July, early August. And so I would still say that Norroa could be a solution. later on after the package is established. So you're right, you have to get to a certain point where the package is established and it and drawn comb obviously helps. But it definitely could be a tool because Anything that is keeping those populations down so that we don't have those huge, huge spikes at the end of the season, which we do I've seen packages taken down too many times by Varroa, even though they were on drawn comb. So I'm just gonna say that it's still Depending upon where you're keeping bees, it still might be a tool you want to look at. Right. Understand the local context. That's true for when Norroa is or isn't going to be suitable based on nectar flows.

22:11 You've got to understand the the mite importation or transmission between other hives in the area. So yes, there's you know, like everything, beekeeping is very, very local. and Varroa control and the use of these products is also gonna be local and requires some local knowledge. Well as always all of these treatment options that are available to beekeepers One of the best sources of information to get up-to-date information is from the Honey Bee Health Coalition on their Varro Management Guide. I know Better Bee has a wealth of information on their website on education and vario treatments. So I encourage beekeepers everywhere to keep on top of the latest and greatest and even the products that have been out for a while.

22:51 Read up on them, see if there's anything new out there regarding those treatment options. Thanks everybody for joining us today. Thanks for David, thank you so much. Your wealth of information is very much appreciated.