Bug Bites! Session 1: Poinsettia IPM

February 9, 2021

Video Transcript

- Good morning, green industry professionals and bio-control enthusiasts. Welcome to Bug Bites. My name is Jeremy, and I'm a greenhouse agent with Michigan State University Extension. This is the first in a series of short seminars led by industry experts. Speaking on topics suggested specifically by growers right here in Michigan. Before we start, I wanted to bring your attention to the Q&A button located at the bottom of the Zoom window. Feel free to submit questions at any point during the presentation, we'll be keeping track and be sure to give our guests a chance to answer them at the end of this session. Also, it's often helpful for speakers to understand the knowledge level of the audience. So we're gonna do a quick poll. So if you had to estimate on a scale from one to five where would you place your knowledge of and experience with biological control, with one being a beginner or novice and five being an expert? And here you go. No beginners here. Okay. So thank you very much, everyone. Our goal here is to get in and out in under an hour. So we're gonna dive right in. Among Michigan growers, the Canadian greenhouse industry is well known for its success using beneficial organisms. Canada is a world leader in greenhouse production and over 50% of the national greenhouse output comes directly from the province of Ontario. All that production needs support from time to time. And our guest today is one of the people that help Ontario's greenhouse industry run as smoothly as possible. And so without further ado it gives me great pleasure to introduce Dr. Sarah Jandricic, Sarah? - Hi everybody. I'm just gonna go and share my screen, and get my presentation up and running. So as you can see today, we're gonna talk about IPM and poinsettia exclusively about Bemisia control from a Canadian perspective. So this is why I have a picture of a Mountie holding a beaver on the screen because I couldn't think of anything more Canadian. And as I was telling Jeremy before, I'm going to assume he's standing in a puddle of maple syrup as well just to make it the most Canadian thing ever. So just to give you a little bit of background on myself why should you be listening to some lady from Canada. My experience is sort of run up and down the East coast of North America. I started at the University of Guelph, which is our agriculture school here in Canada studying Dalotia coriaria, now known as Dalotia. And then I went to Cornell University to do my PhD on the biology and bio control of an emerging pest at the time, which was foxglove aphid. And then down to North Carolina State where I did my post-doctoral research on thrips specifically how thrips behavior changes in the face of predatory mites. And now I'm back up in Canada as sort of the Jeremy of Ontario. I'm the greenhouse floor culture IPM specialist for the Ontario Ministry of Agriculture Food and Rural Affairs, otherwise known as OMAFRA which is a mouthful, but I'll probably refer to it a couple of times in this presentation. And it sounds like from what Jeremy said, the growers there in Michigan are familiar with us up here in Ontario. But for any of those of you joining from somewhere else where our fame may not have seeped to this gives you a snapshot of Canadian greenhouse production. So most of the vegetable production is in Leamington, which is near Windsor, which is sort of across the border from Detroit in Southern Ontario. And then our floriculture production is really concentrated in this little region of Niagara which is across the border from Buffalo. So 82% of the growers in this region are dedicated strictly to flowers. And as Jeremy mentioned, that represents 50% of all Canada's production in this wee little area which has its benefits that I'll talk about in a minute. So just to put this in perspective, in terms of economics if you take the top four growing regions in North America in terms of farm gate sales in US dollars Ontario is actually the third largest producer of floriculture crops behind California and Florida. So we're just beating Michigan, you know, which gives us some friendly competition to work on. So we'll see how that evolves over the years. Jeremy also mentioned Canada's pretty well known for being a world leader in bio-control and what we like to call bio-control based IPM in Canada. So bio-control adoption is around 80 to 90% in flora culture crops. And that's been true since about 2007, and we put a lot of emphasis on what we like to call a systems approach to bio-control based IPM, which is really looking at IPM as a process from start to finish. So from propagation through to finishing, obviously focusing on prevention over intervention, but it also considers all aspects of growing as part of the system. So effective pest control, looking at this diagram here if you can see my little mouse, it doesn't just depend on the right bio-control agents. It also can depend on the plants, picking the right varieties picking the right suppliers and also the environment as well. So the systems based approach can, we've got a lot to talk about there. So instead of talking about that during this presentation for the sake of time I thought I'd just refer you to another webinar we did for Crop Talk Media recently, myself and Dr. Rose Batonhouse, who's the bio-control researcher at the Vineland Research and Innovation Center, which is one of my collaborators. So we gave an in-depth webinar, it's an hour and a half, 'cause we had a lot to talk about. So if you've got some extra time on your hands, we talk about the systems based approach for threats IPM in Canada. And so you can see that we've gone through the whole system from start to finish, and we have lots of tips for you. So that's something you can find on Crop Talk Media, and I recommend it. So how did we get here? How did Canada become a leader in bio-control? I don't want to spend too much time on this but it puts a little bit of what I'm gonna talk about in context. So I would love to say that it was all philosophical, squishy reasons like worker safety and environmental protectionism and growers disliked spraying, and those in part can be true, but the real driver is just our reduced access to chemicals. Some of this is because we're a smaller market. Sometimes registrant's just don't want to put the time and effort into building a Canadian market for their product. We also have fewer registrations based on a lot of safety concerns and it tends to be a slower process. So we get things often 10 years after the States does. And also all our products are re-evaluated for the latest sort of safety information out there every five years. So actually we face a lot of de-registration, so we'll get a new product and we'll be like, yeah, we've got one more product. And then something will get de-registered at the same time. So that's been a big driver. So just as an example of this I took this list of chemicals, the US trade names from the Michigan State site that's recommended for Bemisia whitefly, just as a snapshot of them. And then I gave a snapshot of are these registered in Canada? And you can see some of them like we'll never get named products ever in Canada. A lot of our other products are being de-registered for example, Orthene and DynoMite are de-registered as of December 31st, this year, things like Forbid we've had, but we have developed resistance to, and then other things we just got registered, so Ference, which is Mainspring in the US we have it, but because it's been in the States for so long that obviously puts us behind the eight ball when it comes to resistance issues, especially when we're getting cuttings in from the US where people have been using that chemical for a lot longer. So that brings us to my second big driver of drivers in Canada of why we're leaders in bio-control and that's pesticide resistance. So like I said, because we have fewer products there's fewer products to work into a rotational program. And also, like I said we don't have as many novel products to combat the pesticide resistance that may be occurring when the pests come in on cuttings from our US or off shore suppliers. So with the Bemisia whitefly in particular we have some products that work for B type Bemisia which is, we now know as a separate species of Bemisia that's more susceptible to chemicals, but for the Q type or species of Bemisia really no registered products work for us we'll have to see about Ference Mainspring. 'Cause we just got that registered for this production season. But for us, that's just where we stand. So for those of you who might not be aware of the B versus Q debate, so these both look identical you can't tell them apart by looking at them. So, but you can tell them apart with genetic testing and they do that in Florida. So sometimes my growers will ask me to sort of go into their greenhouse early and see if they have more Q versus B. But I sort of consider that a little bit of an academic argument because both B and Q can develop resistance to chemicals. And also if we're going with a bio-control based program, that's irrelevant. So we tend not to do too much of that unless a grower is really having an issue. So probably the third reason behind how did we get here, the why of bio-control is just our tight-knit area because all that production's happening in that really small area. It's easy to do a lot of extension and workshops and things like that. Also a lot of the floriculture growers here have similar cultural backgrounds and that actually plays a huge role. And most of them are Dutch either first-generation or up to third generation now. And we have to remember that this is where bio-control in ornamentals and greenhouses originated. So a lot of them take trips back every year to the Netherlands and see what technologies and advancements and processes are happening there. And they're not afraid to share information on pest management. I've heard growers say that they don't really want to compete on that level. Like we're all in the same boat when it comes to pest management and they'd rather compete on more sort of like quality volume issues. And then we really have a good communication network. So there's been a longstanding tradition of communication between researchers, growers, industry and extension agents that feeds in all directions. So it's not just that researchers do the work, extension agents take that and give it to growers. Growers really drive a lot of our research projects through their observations. That's the why of it, but I'm sure most of you here today are here for the how of it. So like how exactly do you implement a bio-control based IPM program for Bemisia? So it really comes down to knowing when to apply certain things where to apply them and what you're going to apply. So with biocontrol, there's a lots of different options. We've got things like predatory mites and beetles that attack the egg stages. We have parasitic wasps, mites and fungi that will attack the nymphs, predatory beetles, fungi, and host feeding parasitoids will attack the pupae. We don't really have anything for adults but that's where some of these pesticides in the IPM program can come in. So potentially Fogs or systemic pesticides can sometimes work for adults. And then we've got a systemic or translaminar pesticides and dips, which I'm gonna talk about in a second, that worked for nymphs. So here's basically an infographic or snapshot of what the Ontario Bemisia biocontrol based IPM program really looks like. So we've sort of charted it over time. So the first stage is obviously planning trying to source your cuttings from suppliers that have low whitefly pressure or alternatively, some of the suppliers have actually started implementing bio-control at the mother stock farms. Meaning that those cuttings that come in aren't gonna have the same pesticide residues as maybe from the other suppliers. That's something our growers up here have been starting to play with, which is interesting. And also paying attention to varieties and varieties we know or are highly attractive to Bemisia whitefly. So those are some things you can do, then there's dipping cuttings which reduces initial white whitefly populations. And I'll talk about that in a second. And then at potting we initiate biological control and the hope is that we can continue that all the way through sale. But if not then the option is delayed pesticide applications which started at the last week of September or the first week of October. And I'll get into a bit more why we want to delay pesticide applications if at all possible. So just to go through dips for a second I know Jeremy's talked to you about those but this was research pioneered at the Vineland Research and Innovation Center here in Ontario by Rose Batonhouse in her lab. So basically what you want to do is dip in these reduced risk pesticides. So we're talking about insecticidal soaps and things like BotaniGard. And by immersing your cuttings in these products you're killing the nymphs and pupil stages and really reducing your whiteflies. As soon as they come in the door and our growers here do this a bunch of different ways. The research has mainly been on sort of dipping your cuttings, basically as soon as you get them in, maybe with a small period is spent in a cooler and then dip them and then immediately stick them under mist. And so here are the rates you can use for that, but some of our growers find that logistically difficult. So some growers will do things like dip and then store them in the cooler and then stick. And if they do that they usually cut down the soap a little bit just to prevent any phytotoxicity issues. And this year, a lot of growers have started experimenting with dipping rooted cuttings, actually. So maybe two to three weeks after sticking because what you don't want to get into is that second generation of whitefly coming out. You don't want too many adults emerging and flying off into the rest of your crop before you actually get them get them dipped. So we'll see how that goes. We don't have any direct comparisons going but I think we'll get a sense after this year if that was a successful approach for some growers. And if you want to learn more about dipping and just see the logistics of it and how it's done there are videos on greenhousecanada.ca which is our industry magazine or greenhouseipm.org is a website that myself and collaborators run up here. And you just have to look under IPM videos for that. So why would you dip, I'm sure Jeremy's mentioned this, but basically it can reduce starting populations of whitefly by around 70%. So here's the dip alone, this black line. And you can see that even just the dip alone was more effective at reducing initial whitefly populations in that first seven weeks then parasitoids but the best combination was dips And parasitoids, that light green line near the bottom that really showed you can reduce whitefly to almost zero if you combine these strategies. So now I'm gonna talk about the actual bio-control part. So in Canada, we don't really have one true recipe yet for Bemisia bio control, but growers tend to fall into sort of three basic strategies. So the first one is what I'll call the standard parasitoid program from now on. So this is the parasitoid program that most of the big suppliers have in place. So corporate Biobest, Bioline, they'll usually give you cards that have pupae of both Eretomocerus and Encarsia, two types of parasitoids on the cards that merge and come out into the crop. We also have option two, which is the West Coast program which is pioneered here in Canada by Applied Bionomics. And it bases itself on two organisms, Delphastus, which is a predatory beetle that eats whitefly eggs and also one of the parasitoids, Encarsia. And then we have option three, the kitchen sink approach which is basically just throwing everything at it including different mite species. So just for the sake of time and also simplicity I'm just gonna talk to you about the first two programs and show you how those have stacked up to pesticides over the years. So really what we've done in Canada is for the past 10 years, focused on repeated on farm testing of these different bio-control programs. It really started as an insurance policy. So a few growers, they had pesticides working for them back in the day maybe starting around 2007 but they were concerned that the writing was on the wall that resistance was gonna happen, or we'd lose chemicals. So they really wanted to be true innovators and start experimenting with bio control early so that when the time came and it probably would come and it ended up did coming they would be prepared with bio-control programs. So most of this data is from a single large commercial operation. Each individual treatment was run in a whole greenhouse compartment that had 10,000 poinsettia plants each year, a mix of both reds and colors which is what the grower normally does. And we monitored the crop weekly starting about in early August. And at the end of the experiments costs were determined per pot. And we've repeated this experiment basically we're on our five-year point at this point, and we're gonna keep doing it until we get it right. So just to note on the timing of bio-control agents so parasitoids can be released on just after sticking like on the misting bench. But if you do that, you want to place cards those wasp emergent cards on sticks with a styrofoam cup on top to prevent water from getting on them. So they don't mold before they have time to release. But our grower decided just to release them starting at potting to simplify things a little bit. Delphastus is one of those bio-control agents that's a bit of a canary in the coal mine situation. It tends to react a lot to bio-control or to pesticides residues, pardon me. So the recommendation from the supplier is to wait for four weeks after sticking to release your Delphastus to avoid pesticide residues and then do up to three releases after that. So just a few notes before I go any further, just to correct, maybe correct some misconceptions that I've heard. I've definitely had bio-control reps or growers in the states say does Encarsia really work for Bemisia? I mean, we're taught all the time that you have to pick the right pairs to it for the right pest. So we know in aphids, for example, colamani works for green peach aphid, but it doesn't work for the larger bodied aphids, like foxglove and potato aphid. And we've sort of been trained and learned while Encarsia works for greenhouse whitefly and Eretomocerus works for Bemisia whitefly. But in reality, there's a ton of research papers out there showing that both Encarsia and Eretomocerus both parasitoids and hosts feed on the nymphs of Bemisia whitefly and an added bonus is that Encarsia actually hosts feeds on pupae as well. So you're attacking another life-stage by including it in there. The parasitism just looks a bit different when you're monitoring. So we all remember that classic look of greenhouse whitefly when their parents are parasitized by Encarsia, they appear black and it's really obvious to see, it doesn't turn out the same, Bemisia you sort of get these like dusky brown parasitized whitefly nymphs, as opposed to ones parasitized by Eretomocerus look more yellow. And then when they turn into pupae you can actually start to see like little brown lines in them and you can start to see the sort of like the backend of the pupae is dark and the front end is yellow. So that's, these pictures were taken through my hands lens. So this is exactly what you would see in the greenhouse if you're looking it. So some of you also might've noticed that I was talking about these basic programs that we had Encarsia and Eretomocerus in the standard parasitoid program but in the West Coast program I talked about or I'm highlighted fresh Encarsia. So what does that mean? Fresh Encarsia? Well, it basically means Encarsia that's never been chilled. So if you're getting your parasitoids from a supplier in Europe, they have to be chilled first in order to make the trip on the plane and through the various shipping channels and through the distributor to get to you. But there had been some suggestions in the early 2000s that actually that chilling effect might reduce their efficacy. So like it makes them worse searchers and worst fliers and maybe they don't parasitize as well. So there actually is research to support that, this was research done in Canada by researchers at Agriculture and AgriFood Canada, which is our version of the USDA and OMAFRA staff and also industry members. And so the blue bars are Eretomocerus. The red bars are Encarsia and they looked at a whole bunch of different chilled populations or different ways they get chilled by typical bio-control companies versus these fresh Encarsia which are just the pupae are stuck in the mail. The second they turn into pupae there might be an ice pack that's like really hot in the summer and the box, but that's it. They never spend any time in like a formal cooler. And they showed that flight capacity which is obviously an important characteristic. When you want your parasitoids to go out searching your crop was actually decreased by 20 to 50% when they were chilled. And then when they looked at parasitism rates they also saw this same trend about a 50% decrease in parasitism happens when you chill your organisms before you ship. So fresh is definitely better. Another note is just on treatment considerations. So we're looking at efficacy of bio-control programs compared to pesticides. One thing that's important to remember is rates are governed by economics and not efficacy. So I'm sure I could find you about a control program that works great, 100% kill but it'd be throwing hundreds if not thousands of different bios in there. And it would just be too expensive. So in Canada, our rule of thumb that our it's sort of our the max growers are willing to spend on poinsettias in terms of inputs, and in relation to the profit they got on the poinsettias is about 10 cents per pot is what they are willing to put into their bio-control based IPM program. So in all our trials we're really trying to keep around this mark. So back to our actual trials, what we did, so this is 2017. So the data I'm actually gonna show you has been really interesting over the past three years of data I'm gonna show you we ended up having a high Bemisia whitefly year. So tons of pressure, a low whitefly year and then a medium whitefly year. So we really get to see how all these treatments perform under sort of these different conditions. So just to remind you again we've got this West Coast program, which has the fastest and this fresh Encarsia, which is supposed to be a better bio-control agent in general. We've got our standard program which ends up being really high rates of Eretomocerus and Encarsia. And I'll share more on rates later. And then we've got pesticides. So again, these delayed applications of pesticides on and we chose two mode of actions. So I wanted to take a second to explain why we delay pesticide applications. And it's simply because we want to give whatever pesticides we're choosing in this trial, the best chance of performing well, we want them to succeed. We want it to be a fair comparison. So some work done up in Canada though showed that spray conditions actually promote Q bio-type or Q species of Bemisia. And that's because the B bio-type will become susceptible to the sprays, the Q bio-type, because they're more resistant, they'll hang out and then they'll continue to proliferate in your crops. So what's really happening is if you spray early in your crop, you're promoting this Q species or bio-type which is the bad one. But if you delay your sprays by two to three generations the bees will actually take over. So why is that? It actually comes down to mating success. So it turns out bee species of Bemisia they're pretty good little maters. Like they find their mates really well. They get on with it. They reproduce quickly, Q on the other hand, they get a little confused. So the females will actually try to mate with bee species of whitefly. And as we know what designates a separate species from one another is that they can't inter-mate. So the Q females end up wasting a lot of time sort of farting around trying to find the right partner and not actually producing any offspring because what happens when a Q female mates a B male you basically get a sterile donkey. So this is why we suggest waiting eight weeks to spray so that you're letting those B biotypes or species really get their mate on and start becoming the primary Bemisia species in your greenhouse. And that means your pesticides have a better chance of working. All right. And so how did we monitor in a trail this size? So remember each of these treatments has 10,000 plants obviously we're not gonna survey them all. 'Cause I would go insane, so what about sticky cards? Do we use these? Are these useful or not in these kinds of trials? Well, this was actually work done when I was just a baby scientist. And along with my predecessor Graham Murphy from Ontario and we did some trials and actually realized that the density we saw on the sticky cards of whitefly didn't translate back to the actual density that was happening on the poinsettia plants. So in Canada, we considered these whitefly like sticky cards situation as more of an indicator and not something you can use to determine how well your your program's actually working. So what we do suggest is presence absence sampling which is not as much work as it sounds. So you want to do this on whole plants every seven to 10 days starting in mid August. That's basically when your bios have had the chance to build up, but so have your whitefly population. So it's really starting to monitor them when they're in that delicate dance situation of like will they won't they, how's this gonna work out. Until late October, which after that you're sort of down a path of either pesticides or you're on track with your bios. So that's the critical period. And the rule of thumb that we've gone with is to you want to scout 5% of your crop every time. So when a compartment of 10,000 plants this is looking at 10 to 20 plants per bench. It is pretty fast though. So basically what you're doing is you're picking up these plants at a high angle and turning them so you can see the undersides of all the leaves or the Bemisia (indistinct). And you're just saying, yes, there's Bemisia on this plant, or no, there's not a Bemisia on this planet. So when you walk down the row, if you're counting 20 plants it'll come back and record. Okay, 10 out of these 20 plants had at least one Bemisia on them. The only thing you're gonna want to do is record reds and color separately, because we all know colors are more attractive to Bemisia whitefly than the standard red poinsettia are, and some growers also separate their sizes too, because like an eight inch poinsettia usually is made up of three plants in the same pot. So that's basically three times the plant volume. So it's a little bit comparing apples to oranges. So what happened already? I spent a of time setting this up telling you what we were doing, telling you some caveats. Here's what actually happens in 2017 just to orient you on this graph. All this data is percent of crop infested with Bemisia. And what we've discovered in Canada is this cutoff line in mid-October, so if less than 20% of your plants are infested by the time your crop reaches after bract formation in mid-October you're going to be successful because we figured out that sort of like the amount of whitefly that can be handled that doesn't result in credits from consumers. And I would say this is also a good metric for if you're somewhere else, other than Canada in the States because we actually sell a lot of our poinsettias to American customers, a lot of the big box stores. So our customers are your customers in that sense. And we had the added trickiness of getting across the border. So if we had a huge whitefly problem in a truck that that shipment would be delayed or turned around. So I'm hoping some of you will adopt this cutoff thing 'cause it's a good sort of rule of them. So here's how our treatments turned out. So you can see our low rate of Encarsia and Delphastus, this is the West Coast program the standard parasitoid program, which is high rates and the pesticides all did really well because they're all below that 20% cutoff line. And just to talk about rates for a second, sorry, I skipped over this. So you can really see the difference in rates here. So this West Coast program, we're really talking about 0.2 five wasps per meter squared and to Delphastus per meter squared. Whereas the standard pesticide or standard parasitoid program, we're looking at more like a nine wasps per meter squared. So that's a big difference. So it's interesting that those two are both successful even though their rates are very, very different. So it lends some credence to that whole fresh is better in terms of the parasitoids and also maybe adding the Delphastus product in there too. So what about cost? I think not surprising some of you, the pesticide treatment is, was the cheapest in this year. So around two cents per pot because we only had to use two chemicals. And do one application of each. The standard parasitoid program is a little bit expensive but a lot of growers still swing it here. It's around 10 cents per pot. And then this West Coast program is cheaper, half that, it's six cents per pod. So it gives you some variety in terms of what you're willing to spend in which thing you want to choose. But the caveat here is 2017 was an incredibly low Bemisia whitefly year. So we really need to consider the elephant in the room which is what happens in a bad Bemisia year or what happens in a year when we know we're gonna have pesticide residue and resistance issues, which is exactly what 2018 was. Some of you may have remember getting emails directly from the distributors or suppliers of cuttings, which I really credit them for doing, giving everybody a heads up that like, hey, we've got a lot of whitefly pressure in production this year. It's gonna be these varieties. These are the chemicals we've already used. So you may want to change your rotation program. And this really did translate to high starting whitefly numbers on cuttings. And then in Canada we also had an unusually hot August that year which really didn't help cause it sort of ramped up the the Bemisia production even more. So our trials in 2018 were very, very similar to those in 2017. The only thing we added was dipping at the beginning because we got that warning from the companies which is a great heads up so that we could implement that at the beginning. And then the other thing we wanted to try was sort of like a truncated West Coast program. So we threw out the Delphastus and just used a higher rate of these fresh Encarsia. And that's because we really wanted to determine the efficacy or cost of the fresh Encarsia at higher rates without Delphastus, because it's the Delphastus in this West Coast program that really bumps up the price. That's why it was at six cents. So if we get rid of that we could potentially have a more cost competitive program. So here are our results in 2018. Again, this is percent of the crop invested. Again, our success line is this 20% infestation and you can see our standard parasitoid program did well again, as did the West Coast program. And interestingly, this was a year our pesticides failed and the grower did a lot of different pesticide options. So they used high label rates of contos, distance, belief, which I think is area in the States, anyway, they did Altus, and they did at least two applications of all of those. And interestingly, the Encarsia-only treatment where we were trying to lower those costs still did really well. It was still below this cutoff line. So how did this work out in terms of costs? Well, the cheapest treatment ended up being this truncated program within Encarsia, fresh Encarsia only, which turned out to be three cents per pot. And interestingly, our pesticide treatment ended up being the most expensive one. And that's because of not only the products used and the time involved but the grower ended up losing around 9% of their crop. That was unsellable to two really high Bemisia levels. So this is actually what happened over time in their crop. So you can see that all the bio-control programs were about the same and kept levels low but at the sort of end of the monitoring season which is sort of like our do or die time, you can see that this grower had 60% of all his points that he has in the chemical department infested with Bemisia. So that didn't work out. So as the grower put it, costs are relevant if you can't control the pest. So this was a big hit for them. They felt like it was a big fail. And I want to come back to this slide where I mentioned how rates of either bio-control programs or pesticide programs are are governed by economics not efficacy, but that experience with this grower really led us to add you also have to think about, well, can you trust it to work? So what we're really looking for is a program that's around or under 10 cents per pot, and it's reliable. So for our grower involved in these trials he decided he was done with pesticides and has continued to say, that's not an avenue that he would wants to go down. So what we're really invested in now is again just trying to tweak this program. So it's more cost-effective. So in 2019, we did trials very similar to the 2018. We dipped again, the only thing we modified this year was this West Coast program. We decided to not introduce Delphastus at the beginning when it was recommended, but instead see if we could save it from more of a rescue strategy that would help bring down the cost potentially. So like potentially we would end up with two compartments where we just used fresh Encarsia and maybe we wouldn't need Delphastus at all but if we did need it, we said we were gonna use it in that compartment. So 2019 ended up being a medium whitefly year, and here are our results. So our standard parasitoid program at high rates once again performed really well and is well under this 20% cutoff line, the West Coast strategy with delayed rescue Delphastus, which we did end up meeting came in a bit above our cutoff line. And our Encarsia only low rate sort of cheap program also came in a bit off the cutoff line. So I can hear all of you saying but you said that was the cutoff line. So doesn't that mean they weren't successful? Well, this 20% infestation rate is really just like a rough benchmark. It's a rule of thumb, we're trying to give growers to sort of know when they should worry or not worry but it's not the end all and be all. So really what happened here was that the grower considered all of these treatments successful because they didn't have to spray. And in terms of costs again this Encarsia only was three cents per pot. When we added Delphastus in later we actually ended up increasing our cost of this West Coast program. So that was kind of an oopsie on our part. And the standard parasitoid program is still the most expensive, but it seems very reliable. So again, just back to the 20 cutoff line for a second, when you start to creep near it which we obviously realized before this, these were our final results at the mid October point. So before that we noticed it was creeping up to the 20%. So then what you really need to do is spend some extra time instead of just doing the presence absence but also making notes sort of characterizing your population of whitefly. So what I mean by that is sort of starting in this late August, early September section you can sort of like relax before then, 'cause your your whiteflies aren't very high your bios are building up, but starting around this point you want to start paying attention. And if you get near that 20% cutoff the other things you want to ask yourself or is your main variety affected. So your reds, or are you just seeing high numbers in your colors or potentially you could do spot sprays. Also where are the whitefly? Are they on the old growth, which suggests they came in with the cuttings, and it's old populations that maybe are being taken care of by vial control or are you seeing lots of whitefly on new growth which is sort of an indicator that they're not being successfully controlled and they're being able to move around. Also, you want to see how many dense colonies are actually on your plants that have whitefly on them. So in that whole presence absence often we see what we call onesy twosies. Like you pick up a plant and yes it's checked positive for whitefly presence, but really it's because you saw like one adult on the top and like maybe like a hatch pupae on the bottom or something like that. But if you're seeing leaves that are covered in 30 to 40 whitefly nymphs on all these sort of checked off plants, that's a bad sign. Another question you could also ask yourself is are you seeing evidence of your bio-control program working? Are you seeing lots of parasitized nymphs and pupae are you seeing host feeding? If you're not seeing those things or your parasitism rates look really low like 30% that's when you would want to go in at this point and consider pesticides. And at this point we would probably recommend drenching softer pesticides. So things like Beleaf, Altus and Mainspring which is pharynx in Canada, which are known, especially when they're applied at drench to have sort of less impacts on parasitoids. So the idea here would you, after this point you'd be getting the benefits of the pesticide you applied hopefully, but also your bio controls could still work through this period. If you go straight in at this point with a harsh chemical like orthene, you can just basically just kiss your bios goodbye. So you're not getting any additional support from them. So you might as well start off with one of these softer ones. And then mid October if you're still really concerned about numbers that's when you can start to go in with some with the harsher stuff. The whole idea with this whole timing and cutoffs and characterizing the population, blah, blah, blah is what you're really aiming for is to have less than 20% of pots infested with Bemisia whitefly near sale. And that's because that's the level we know once they start going out the door can be tolerated by consumers and doesn't lead to credits from customers and also gets through that border check for us. So I've thrown a lot of information at you. I'm sure you've made some of your own conclusions but here's some of my conclusions so far and we are continuing this work as we always do but here's what we learned to date. The first thing, the first take home message is that bio-control can be more expensive but it consistently works. And for growers up here in Canada, that's a lot of peace of mind. So the bio-control programs we tested in this super highway flyer in 2018, when we knew the whitefly would be high on the cuttings and we knew they would be resistant to pesticides, a lot of them. And we knew a rotational program with pesticides wasn't super possible. Our bio-control programs, ranched in cost from three to 12 cents per pot, but they were all reliable. And we had no crop losses, whereas our pesticide program which was basically the grower throwing everything they could at it, was not reliable in that year. The second take home message is that bio-control can be successful and be cost competitive with pesticides. So I think that's sort of a misconception that's still out there that it's always gonna be more expensive than pesticides and that's just not true. So for example, in 2017 we had our low whitefly pressure year. Our pesticides were great and it was only two cents per pot but in a 2018 high Bemisia year, the cheapest treatment was actually the Encarsia only treatment. So this does take a bit of fiddling around. Like if you just want to not think about it and go with the standard program, it is gonna be more expensive. But if you want to take the time and do a lot of iterations each year and sort of learn what works for your farm and your pests and work with your industry members, your bio-control reps on trying to get that cost down. It is possible. The other thing I would say. (dog barking) I knew that was gonna happen, package delivery. I'm sorry about that. The other thing we learned out of this bio program is if you want to try to decrease the cost, then you're likely gonna have to have a more watchful eye on them. So we know this standard has been reliable, has been really reliable in all years, we saw a little bit of variation in the Encarsia program. So it just means spending a little bit more time characterizing the infestation before you react. So as long as you're comfortable with that 20% cutoff and making sure you are willing to spend a bit more time going in and monitoring to see what is happening these cheaper bio-control programs can work for you. Okay, barking storm seems to be over. Another thing we learned from this was Delphastus if that's a predator you wanna use, is seems to be better used preventatively as the bio-control company recommended. So we tried to jigger with it in 2019 and see if we could, see if we could hold off and use it as a rescue strategy. And all we ended up doing was increasing our costs. So it really does work better earlier on in the crop. So learn from our mistakes. And lastly, I would say the final take home message of this sort of Canadian study in bio-control based IPM is that even using bio-control as a tactic to delay sprays if you still want to use sprays as your primary tactic, bio-control can help you get through to sort of that late September early October period, where you know at that point your population is going to be mostly bee species and not the resistant Q species. So it just means your pesticides are more likely to be successful, and you're not going to have to do like a super heavy rotational program. So I think of bio-control and this sort of IPM based system as like buying insurance through your pesticides. So the last thing I'm gonna leave you with a some of these topics I went over, maybe not in depth enough for some of you that want to implement them. So there's a lot of information on my blog, which is on floriculture.com. You can register for it and it will send you updates as I post them which is about two to four times per month, basically but depending on what's happening in the industry. So I try not to like overwhelm people too much but for an example, one of my blog posts from last year was bio-control of Bemisia seven things to look for before you turned to chemicals. And that was really doing that characterizing of the population. And it has pictures of what you should look for and all that sort of good stuff. So you can also using this left menu go down and search for posts on specific pests like whitefly or even specific crops like poinsettia. So that's really all I've got for now. I'm gonna stop sharing, maybe I'll keep sharing my screen and maybe go to specific slide if people have questions about specific things that I share. - [Jeremy] Fantastic. Thank you, Sarah. - Sorry about the barking. I knew we were taking a chance. - [Jeremy] Well, that's just life these days, it doesn't bother me and I'm pretty sure it doesn't bother anyone else. We can all can appreciate what it's like now. So I've got a little bit of housekeeping before we get into the Q&A. - Sure. - [Jeremy] So first this session is being recorded and will be available sometime in the near future. So we will send out an email with a video link to all of the registered participants when it becomes available. And second, your feedback is super important to us. It is what helps guide our effort to develop interesting and relevant programs for the benefit of the greenhouse industry. So when you leave the seminar today, you will be automatically directed to a two minute survey. I made it super short. It does not take much time. And the results are really quite meaningful to both Sarah and myself. We sincerely appreciate you spending a few moments to share your thoughts with us. And so, okay, Sarah, it looks like I have at least one question here. Are you ready to go? - I hope I can answer it. - [Jeremy] Yeah, it's going to be answered live. So this is going back to the some of the earlier trials you were running. Was there an untreated control? And what is the typical range of percentage crop infestation rate without treatment? - Yeah, so we did not do an untreated control mat and that's because when you're doing these on farm tests and this grower has been very generous to give me basically four compartments with his highest value crop and just been like, go, and if you screw it all up, I'll try not to kill you. You know? So we decided that's why we were using pesticides at first which was a type of control. So instead of using an untreated control you can use an industry standard. So the pesticides were industry standard and we were comparing bio-control to them. One thing I didn't show you was in 2017 we actually did the a lamonicus only treatment because I was curious to see how that would contribute to bio-control on its own. And essentially that ended up being an untreated control because lamonicus as you know is super expensive. It's about three times the price of source BI, as a predatory mite, and the low numbers we put in just like, didn't do anything. And that was about, we had about 50% infestation. So I would say in like a normal year if you don't do anything by mid October you're at 50% infestation, which means by late October sale you can be up to 80% infestation which is a serious problem. So I hope that helps answer it. I'm sorry. I did my data a little bit. - That's okay. That's okay. Those are great considerations. I had one, 'cause I'm not seeing any more I don't think, so in Michigan (indistinct) is commonly integrated into bio-control programs. And it's generally considered to be a very low risk product. I call it one of the softer products and you really caught my attention when you said that neem products are likely never to be registered in Canada. I'm just kind of wondering why that would be - Yeah, not for floriculture crops anyway, I don't really know the backstory behind that. All I know is that we've been banging our head against the wall on that particular wall for about 10 years now. So I don't know if it's something in the safety profile or more just like a market issue. 'Cause that's what it comes down to. Like that's fair, we're a much smaller market than the US and sometimes the register is just it's too much time and effort and to get through our registration system, like it can be a pain in the butt and we acknowledge that and it can take a long time. - Okay. I've got one more question and he's asking you to kind of for a scouting report from Ontario. So how's 2020 shaping up overall and are whitefly numbers, average, light or heavy? - Good question. It's a real mixed bag. And it's interesting. So some of my growers had really high whitefly levels in mid August, which is like like just in this presentation, I said, oh, you probably don't need to worry about them until like late August. But we went in early and we were like, geez, like things aren't looking super good. And it was from a certain supplier but other people from that same supplier weren't seeing any whitefly pressure. So we suspect it may have to do with the particular farm that it's coming from with that supplier. So it ended up sort of being all over the place even within that one grower that was seeing 60% in some but other compartments were fine. Luckily, the bio-control programs because we're not doing pesticides anymore in our 2020 trials, the bio-control programs all seem to be able to get on top of it. And we're feeling pretty good about where we are now and we don't think we're gonna have to spray, but so I would say this year's posed another interesting conundrum I guess, where it's gonna be a low Bemisia year for some people and a high Bemisia year for other people. And I think we're gonna see that more and more as like I said, some of the suppliers start playing around with using bio-control, which I am fully on board with. Canada's been lobbying for that for years but it may have some interesting repercussions or hiccups that we're all going to have to deal with for awhile. - It takes time to work the kinks out of it. - Absolutely. - Okay. So I have a really quick question here. So does fresh Encarsia cost more? - Well, as you can see, because I mean animal per animal probably, but the rates you can put in because it's a better parasitoid and has better searching capacity the rates are so much lower. So like I said, in some of those rates I was showing you the recommended rate from the distributor is 0.2 five wasps versus nine wasps per meter squared for the chilled Encarsia. So I think that's where the cost savings is coming in. So like dollar to dollar animal to animal I'm not sure where it works out, but the rates you can get away with they're so much lower. So this year, one of the things we actually want to play with is bumping up those Encarsia, those fresh Encarsia rates even more like, what would it look like if we put it in nine lots per meter squared of fresh Encarsia in terms of both cost and efficacy, lik, will we just have like zero whitefly? That would be amazing, but I'm sure it won't be that perfect, but it, but it was a question we have in the back of our minds, as much as we're trying to like reduce the program and reduce costs. I think this year we were like we just want to see what happens, you know? - Yeah, the difference between the fresh and the H was really remarkable. That looked like 20 if I remember correctly. - Yeah, yeah. - From your chart. - Yeah. And they are available in the US or they can be. So I know for sure, there's a distributor in New York State that can have the fresh Encarsia mailed to them IPM labs. So there must be other people as well. So it's not just an Ontario thing. That is a possibility in some areas as well. - Yep, I'm familiar with IPM last. So if anyone has a question, just shoot me shoot me an email. Okay. I'm not entirely sure if we have any more questions it doesn't look like it. Let me wait for just a minute. If anyone has any further questions while we have Sarah's undivided attention - I'm also open to emails at any time about any of these presentations. You can find my information on Flora Culture or I'm sure Jeremy will share it but it's Sarah.Jandricic@ontario.ca. So you just have to figure out how to spell my last name correctly. And I'm happy to answer any emails. - Okay. I am not, double checking one more time. I'm not seeing any, perfect. Okay. So without any other questions I think that really wraps up our first session. Thank you for joining us, Sarah. We really, really appreciate your time and your expertise. I wanna thank everyone for joining us, be sure to tune in next week for a session on aphidoletes and parasitoids with Kelly Vance and his IPM team from Beneficial Insectory, parasitoids are so awesome. I've actually personally used both of these in combination. It was a tremendous effect on on aphids in my tiny little greenhouse. So this should be a really fun session. Please note the special start time of 1:00 p.m. because they are on the West Coast. And they weren't really receptive to the idea of an 8:00 a.m. webinar. So it's gonna be at 1:00 p.m. next Tuesday. In the meantime have a great week, everyone.

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