So I’m anthony Hansen. I’m a phd student at the university of Minnesota, and I’m also originally from Bruton Minnesota grew up on a farm [there’s] come from beef cattle background different forage crops, and they’re kinda Standard field crops as well And my work involves host plant resistance With using that against Soybean aphid so this talk will cover is a general background of host plant resistance What’s available for Farmers and then specifically my research that Sarah? Organization provided a grand for it’ll be kind of a two-part area So start off with Soybean aphid I’m sure most people are familiar with it, but if you’re not It’s our primary Soybean tests in the upper midwest it’s primarily problem problematic because it can reach high population densities it can [reap] [use] really quick on a Soybean plant and There are a couple different control methods the main one is insecticides, and that’s pyrethroids organophosphates for conventional use primarily and application [o’s] insecticides is only recommended if [you] got in the field and scout and you find a fence out there and If you get to the point where you find on average 250 aphids per plant we call that the economic threshold when you’re supposed to Start looking into applying insecticide And that’s to prevent if it’s reaching higher level of infestation called the economic entry level which is 675 aphids or plant and that’s when the amount of yield lost those aphids would cause would justify an insecticide application So that’s one method But one other control method that’s showing some promise is using host plant resistance or resistant Plants And there’s a couple different ways that Plans can be resistant to an aphid or another insect The first is called anti Bios asst and this is basically a fancy way of saying that there’s some chemical in the plant some compound Natural defense mechanism that will reduce an aphid survival or reduce its reproduction on the plant as well So [they] see lower population growth there another one oh Okay Another is an ties enosis, and this is basically Repellency so an aphid may not be is attracted to that certain plant and there may be other factors in that plant It’s actually a physical barrier such as trichomes and those are those little hairs you might see on the underside of the leaf a plant can have a lot of those and actually act as a defense against athens trying to get onto the leaf and start treating or laying them and There’s a few different genes that have been found so far that will provide either an tobias’s or anti Zoonosis And they’re called Rag genes or resistant Safest glycines and they’ve been found by looking at other plants in Asia where the Soybean aphid is native to and screening those for resistance and then if they find a resistant straight, they’ll breed that into the current varieties we have here and I’ll be referring mainly to Rag1 and Rag2, but sku mind that there’s a bunch of different rag genes so if you’re looking [for] Soybeans that would be resistant soy bean aphid you want to be looking for something that says it has Rag one or rag to and that’ll be specifically that it has some kind of aphid resistance So it’s just an example graph showing how resistance works this graph shows mean number of aphids per plant so many days after infestation, so a Susceptible plant will have a fence on it that will decidedly increase in population And they can reach high levels in this case it takes about 1,400 aphids a resistant plant like these two at the bottom You won’t see you’ll barely see any population growth on those plants they’ll either be a flat line or very slow population growth and This is just for a very short snaps up shot at the end of the growing season You can look at how many aphids he had total over that whole season So one concept I’ll be using a bit as cumulative day five days and for those that are familiar with it It’s just kind of a cumulation of over the entire season How many exits that you have so more cumulative days more e-fits yet? And this graph shows? Different varieties that either are susceptible they don’t have it resistant straight and then there are others that are just one resistance traits such as rag one or rag two and then you can have what we call a pyramid which is two or more resistance traits in that same and this graph shows high cumulative days for all these susceptible Plants and various locations and ears so these different colors show say, Minnesota, South Dakota ETC in different years we’re going to go to Resistance traits we can see that most of the time there are Fewer aphids, and they’re below the economic threshold this red line But there are some cases where? you might have a resistance straight, but you still have a fitting levels and You can see this a little bit in this graph that there’s very low wave numbers on that pure emitted line So that’s important concept thinking about if you’re going to be getting a variety if you find one that’s permitted that will help you out especially with yield because Like this graph shows this you’ll loss if you have a susceptible plant you’re going to lose a lot of yield With Ragueneau Rag2 alone you do get some reduced Yield loss but you still can see you loss that pyramid line you see next to no yield loss, so Thinking about different genes that are being involved and the varieties might be interested in That’s always an important thing to think about if you’re planning ahead for next year, or this year I guess now but so one reason why a single gene trait might be overcome by aphids is by what we [call] a third biotypes and There’s a few different biotypes So we call them biotype 1 2 eTc and we call biotype one a virulent which basically means if that aphids on a Resistant plant it’s not going to do so well, but some like biotype to it will be virulent which means it can overcome resistance Specifically to the [brag] one trait, and there’s a few different other cases of biotypes And you can get to one like biotype for that can actually overcome those pyramid lines, so that’s justification For actually finding new sources of resistance and pyramiding more of those genes together And that’s part of the work that we’re doing at the u of m right now I will be presenting on that, but just screening through a bunch of different lines trying to find other traits We can breed in two lines set either will be publicly available or that other breeding come these will use So transitioning a little bit. We’re talking a little bit about insecticides at first and then also It was just in plants, so one concept Thinking about all those together I’ll transition into some of my work is integrated pest management, so we’re wanting to use Different control methods as best. We can at the right time and try to reduce any like non-Target effects on Insects that we want to have around in our fields, so think about insecticides is the main control method There are a couple issues that come up with that [one] aspect. We actually have some issues with some organic insecticides that organic growers can use is that they don’t seem to work that well for Soybean aphid and that’s what we’ve been hearing from folks in the field and Seemed a little bit which I’ll show later in our experiment then also overuse of insecticides in general that can have non-target effects on your natural enemies like lady, beetle or Parasitoids, and you’ll hear more from George heiple about that after my talk about just natural enemies in General then also for resistant plants one thing we’ve been finding is that it’s sometimes difficult to actually find varieties that have those resistance traits and They’ve been on the market since 2009 but that’s been a little further down south up north here where we have early maturity groups. It’s been a little tougher to find Resistant plants and just looking through seed catalogs even around here I haven’t seen too many companies that advertise a food resistance But there have been a couple here and there so you [might] have to search for it a little bit so that leads into my actual research project thinking about what happens when we combine both host plant resistance and insecticides and In this case I was thinking about if you have a resistant plant is that going to? Increase the susceptibility of those aphids to other insecticides But that could also be flipped around saying maybe they’re deceptively might be decreased or there might not be an effect at all so that’s the general research question we’re posing and I kinda have just some graphs to kind of show the concepts of what we’re working with a little bit because We talk about interactions a lot so this graph shows susceptible and resistant Plants But then also and the white is if you had no one sex side treatment black is if you use an insecticide So on a ceptable plant you may have a higher number of aphids you have an insecticide treatment it should decrease if you move over to a resistant plant if you use insects that on that if that decrease Nathan’s after treating was the same as on the supple plants you call that an additive interaction or basically that the two treatments either insecticide or Resistant plant they don’t affect each other so they’re compatible but they’re not adding to each other at all The other two the one I’ll be focused on primarily is synergistic interaction so if you look at additive interaction those two lines are parallel and A synergistic interaction when you have a resistant plant that’s treated with an insecticide Jose if it’s are more susceptible so you’d actually have fewer aphids on that plant and that’s the concept that we’re hoping might be utilized and our research and Another that we want to be a little bit worried about is Antagonistic which basically means those aphids on the resistant plant might actually be less susceptible so we wanted to try to figure out What actually would happen because no one’s looked into this field for Soybean aphid before? So especially for a synergistic interaction, there’s been some other cases corn earworm rice plant hoppers where they’re on the resistant plants And they’re more susceptible and Let’s go through [some] of the potential outcomes for our actual research we were hoping with that Synergistic interaction that there might be fewer insecticide applications. If those athens are more susceptible that might knock their populations down enough where? someone might not have to spray more than once in a year or Else thing about insects that efficacy for the organic growers since there’s limited options there we might be able to take in this exercise that doesn’t work that well and At least in general fray Feds, and if they become more susceptible that could work well for both eighth and control But then also think about natural enemies where there might be less non-Target effects because those natural enemies aren’t affected by the resist plant and Think about this interaction, that’s another tool We like to say your integrated pest management, or iPm toolbox trying to add more tools for farmers to use for whatever methods are using So move into actual study basically what we did was planted acceptable wine and a resistant line Rag one Was our gene that we use and we applied different insecticides one was a zero Which is organic proven sex site has pyrethrum? And Neiman it as a mixture and [then] to conventional insecticides one was Laura’s ban the other was warrior And then we also had our control plots which were no insecticide, so in 2013 We Actually had relatively low populations of aphids say it Increased a little bit and they can install doubt the rest of summer at least in Rosemont where we had our sites So we actually had cages we put up as well besides monarchists Athens and the open plots so we didn’t fests those cages after right after a spray and see how a fat levels increased and That was also meant to keep natural enemies out so we could try to exclude any effects of natural enemies in the plant as well 2014 we had [hire] a fat levels, so we displayed at the economic threshold and monitored aphid populations afterwards and let me just put that up quick, so [this] shows our field data for that first year with to the conventional insecticides chlorpyrifos land beside Hallo [thirrin] and This is similar to those interaction graph that showed you earlier. We have no one sex side treatment in these white circles here and You can see both insecticides there were fewer aphids and both ceptable and raglan plants and then also because in such sad treatments but we also had those some Parallel Lines or an additive Interaction for chlorpyrifos, but then the other insecticide, we actually had that synergistic interaction except for zero that the organic improvement sex side unfortunately We actually didn’t see any effect. We actually do the statistical tests on this the insects I didn’t work in either the susceptible or the rag1 treatment so we included all these insecticides again for another year and the similar Occurrences happened 40 at least where [it] didn’t work again that year And that’s something we’re still trying to figure out what’s going on through this organic insecticide That’s not working out but for the other two conventional insecticides They actually switched their roles, so one of them actually had a synergistic Interaction and the other one was additive whereas the year before They switched the roles for that interaction type. So there’s something different going on each of those years So what we did after all this field data was to do lab bioessays and this is basically just taking a controlled dose of the insecticide trying to measure mortality and reproduction and we just place a fits into a little cage on a leaf and use a clip cage to keep them on there and They’d be on that whole plant for two days Being exposed to that insecticide and we use to to insecticides one was the conventional lamps I hallo [theryn] The other was as era as the organic and a zero is ongoing So I’m just going to present quick What happened with warrior or lime say Holliston Warriors a trade name of that insecticide if anyone’s interested? In this case the lab assay actually didn’t show the same effects that we found in the field that first year So we’re using these slab bioessays try to figure what the mechanism was that we found in the field But we’re still working through what’s going on, but it’s just a good example even though we didn’t find that synergistic effect there’s still fewer aphids in both your control and treated because of the insecticide So our main conclusions we didn’t find an antagonistic interaction which basically meant it didn’t make the aphids more or less susceptible to insecticides and that would be one concern that if people are out there spraying and that they have to spray and A resistant plant that that might cause problems for resistance management of insecticides But our actual data on the conventional insecticide showing those additive or synergistic interactions We aren’t sure what was going on between those two years because the data was the results were different each year That could be because of weather one year was particularly hot and then another year we had a lot of rain afterwards and there are different chemistry’s so that might be something to think about for future work or additional insecticides to test is thinking about different chemistry’s that they might have and Yeah, as I mentioned before as era the organic insecticide wasn’t effective and as a littlest point because we were hoping that We’d find an interaction there and have it be a more viable option for organic growers So we’re still looking into that area a little bit if there are other organic insecticides that might work out better And like I said we have additional bioessays going in the lab to winter right now So we’ll see if we have any additional results there So for a general look there are some insecticides where aphids are more susceptible to them on resistant Plants So that key concept can move us into this next step think about okay? what other insecticides could we find this in and could there be some benefits to that and that could be because it’s safer for natural enemies that you might have better aphid control and not have to worry about non-Target effects so much and also, if there could be something available to organic growers for another control method and Then also thinking about back to this I p.m.. Tool box is you know there are many tools available right now? They’re scouting or just implants insecticides, and then also the natural enemies which you’ll hear about a little bit later so how do we include all these different control methods or evaluations and Try to figure out what’s the [best] way or most efficient used for farmers in different situations? Conventional worst Organic or different areas of the country as well so with that I disliked acknowledge ceragon for funding the research and also, Minnesota Soybean growers and mgK for Supporting my graduate student fellows our research as well, and that I’ll take any questions people have someone so the question is it’s whether differences between Rag1 and Rag2 and Reg one is just a gene that will confer resistance. So when you go to find your variety or someone’s breeding they’ll take a plant with that gene in it and if It has reg one in it then that offspring should have dragged one as well And if that offspring has reg one in it it will be resistant to the aphid So does that cleared up? Yeah, so for the rag1 and reg yeah, so for ag one and rag2 you just take one plant that has rag1 in it not with right to read them together and That’s it yeah, so the question was what mode of action is for RaG1 and I haven’t seen Enough information fully answer that the thinking is that there’s? Well, there’s a mix part of it Santa by Osis which means there’s [probably] some chemical defense going on there but there’s also an ties gnosis where they’re repelling the aphids and It’s mainly been characterized saying that the aphids are being repelled or they’re having lower population growth But why that’s happening? I haven’t seen any information on that yet. So that’s probably ongoing research somewhere I’m sure so the question was if there’s a yield drag on Rag1 and Rag2 [I] know for reg one at least There’s not a yield drag I haven’t seen examples for all the other reg jeans and I Can’t say for sure and rag2. I want to think there’s an a yield dragged there, but they’ve definitely tested Rag1 And there’s an eel drag Yeah, so the question was if or what the availability is of Rag1 and Rag2 plants and There are rag one or just reg one varieties alone Available that I’ve seen it’s tougher to find them I think I was just looking through on some seed catalogs And they had them but if you go further down south there’s definitely the Rag 1 plus rag2 So I get this you’d have to check with your local seed provider