Title: Row Crops Radio: Rice and Soybean Seed Treatment Considerations for 2021, with Gus Lorenz, Ben Thrash and Nick Bateman (4/2/21) 

Welcome to Arkansas Row Crops Radio. My name is Gus Lorenz, IÕm Extension Entomologist for the University of Arkansas System Division of Agriculture. I am joined today by Nick Bateman, Extension Entomologist & Ben Thrash, also Extension Entomologist. We wanted to do this podcast today because weÕve been getting a lot of questions about insecticide seed treatments, about the value & what they bring to the table. This is the time of year growers & consultants are making decisions on what to do & everybodyÕs looking for ways to cut cost as much as they can. We understand that but at the same time we feel like the insecticide seed treatments bring a lot to the table, so what we thought weÕd do is talk about particularly rice & soybeans today & go over those things about what we see with the seed treatments & share a little bit of the data weÕve collected the last several years with seed treatments & weÕll go from there. IÕm going to hand it over to Nick & heÕs going to talk a little bit about the rice & insecticide seed treatments.

Talking about cutting money up front, thatÕs one thing we canÕt do in rice production. We see too big of a benefit from insecticide seed treatments & the two main pests that we targeting with those insecticides seed treatments are going to be grape colaspis & rice water weevil. Grape colaspis also known as lespedeza worm is a major pest all up through the White River Valley, The Grand Prairie, places in Ashley County down south. Basically anywhere we have those thin, light White River silt loam soils . TheyÕre going to be a major concern & really the only control option there is the use of Neonics, so itÕs only going to be Cruiser or NipsIt. They provide great control. Now with rice water weevil, we do see some control there with Cruiser & NipsIt. What we also see is that we get about 28 to 35 days of control with these seed treatments. So if weÕre planting early, likeright or the near future the odds of us going to permanent flood in 30 days after planting is going to be pretty slim. But we also have Dermacor & Fortenza which are diamides. They last for a really long time out there & they give a lot longer control, better control of rice water weevil. And they also provide some control of armyworms. We saw that quite a bit last year, especially in northeast AR. Both armyworms, true armyworms & cutworms are controlled with these seed treatments. We saw a few fields of row rice that had Fortenza insecticide seed treatment that had great control of armyworms. And speaking of row rice we see benefits there adding those diamides whether it be Fortenza or Dermacor , with Cruiser or NipsIt for control of rice billbug. From a yield standpoint looking at just NipsIt or Cruiser, weÕre looking at about a 6-7% increase over a fungicide only, or untreated. If you look at Dermacor or Fortenza either one alone, youÕre looking about an 8-9% advantage there. But if you look at a combination of say Cruiser with Fortenza or Cruiser with Dermacor, youÕre going  to a 12-14% increase. And that really doesnÕt matter if weÕre talking about patty rice targeting grape colaspis or rice water weevil, or row rice targeting rice billbug. Those combinations we see a better yield advantage than one of those products by their self. 

We get that call a lot about the Fortenza &  Dermacor, exactly what theyÕre bringing to the table & I think you pointed that out real well. The good control that we get with the caterpillars like fall armyworm & cutworms & that kind of stuff. A lot of people ask, how long of protection do I get? Based on the studies that weÕve done, weÕre getting at least 60 days with Fortenza & itÕs even more with Dermacor. So for those guys up in the northeast part of the state that have an issue with stem borer, weÕre also getting some protection from that. So those diamides really provide a level of protection for these pests. They donÕt have grape colaspis up in northeast Arkansas & many parts of southeast Arkansas, so the cruiser & the nipsit are providing some good protection for great colaspis & a little bit for rice water weevil & they are obviously better than nothing at all. But certainly for those growers that are considering to seek treatment, those products provide a lot of control over a lot of the pest problems weÕre currently experiencing. 

Stem borer numbers it seems like the last few years are really going up. WouldnÕt you agree? 

Yeah no doubt about it. We saw some fields up in northeast Arkansas last year where there was definite yield loss. Normally with stem borers we see a blank head here or there sort of thing, up & down bar ditches & what not, but it seems like thereÕs some pockets up there that are really starting to build some numbers. Dermacor or Fortenza would provide protection there. That can protect some of that yield loss potential. 

And the points you made about the rice billbug is spot on I think. WeÕre beginning to plant more & more row rice every year & based on what weÕre seeing in our studies, that combination of the neonic & diamide really provide a level of protection that weÕre not getting with anything else, wouldnÕt you say? 

Yeah, if you look back through the past two or three yearsÕ worth of seed treatment trials that weÕve done, in very heavy pressure from rice billbug, but if you look at just a Cruiser or Nipsit alone, compared to a Cruiser or Nipsit in conjunction with Fortenza or Dermacor, thereÕs about a 10 to 15 bushel advantage with that combination. I know a lot of guys donÕt want to spend that extra money. If youÕre looking at Fortenza on a hybrid, youÕre looking at $7.50-$8. If youÕre looking at Dermacor, now youÕre talking 12ish, so thatÕs quite a bit more money up front, but when weÕre talking 10 to 12 bushel advantage pretty easily in row rice, I can make that pay for itself. And itÕs the same for rice water weevils. ItÕs pretty easy to make that combination to pay for itself. 

And one last comment on IÕll make, I talked a grower up in northeast Arkansas into trying the seed treatments. ThereÕs a big area up there that donÕt use them & he had never used an insecticide treatment in rice & last year he finally decided to take my advice & put it out on a few fields up there. He commented all year long about how the rice jumped out of the ground, got a great start. It looked better the whole year compared to fields he didnÕt put it out on & he felt like it had some real value to him. 

ThereÕs another field we looked at up near Paragould last year where basically the guy ran out of treated seed & he swapped over to some untreated & planted the last quarter of his field or so & all year long there was a height difference, a maturity difference. Matter of fact about 10 days after it come out of the ground it made you think of that untreated was ever going to come up, but it eventually did, but there was about 4 or 5 bushels difference there & there was no real rice water weevil pressure. Just that seed treatment alone out there & getting out of the ground & going, that was worth 4 or 5 bushels on its own there, regardless of insect pressure.

I guess thatÕs about all we want to do on rice right now. If you have any questions donÕt hesitate to give us a call. ThatÕs what weÕre here for. I want to talk a little bit about soybean seed treatments, so IÕm going to hand it over to Ben Thrash.

WeÕve been getting some calls about people wanting to cut out some insecticides seed treatments on their soybeans & we donÕt really recommend that in Arkansas. You may hear about up in the Midwest & over in the east, people arenÕt seeing too much value with insecticide seed treatments, but we do see value in Arkansas with insecticide seed treatments on soybeans. So what are we getting out of that? Our research shows somewhere close to 2 bushels of yield advantage over a non-insecticide treated soybean & weÕve had some research over the past couple of years where weÕve been looking at them across several different cover crops. WeÕve looked at some insecticide seed treatment in  rye,  winter peas & then a blend & we compared that to a fallow treatment & it didnÕt matter what cover crop we were in or if we were in the fallow, it was pretty consistent. We had a 2 bushel yield advantage over untreated soybean seed. And with soybean prices being what they are right now, I think I just checked the other day & theyÕre around $14 per bushel. Two bushels pays for itself pretty quick. That gives you protection from some three cornered alfalfa hoppers early in the season. Remember three cornereds later on in the growing season, they donÕt hurt you. But on those small plants less than 10 inches, they can actually cause a little damage. It will also protect you from things like bean leaf beetles. So especially if youÕre going into a cover crop, you want to put a good insecticide seed treatment on there. It will protect you. It will keep you out of  trouble in a lot of cases. 

Yeah Ben, the consistency with the yield increase tells it all but at the same time my concern a lot of times is with those when we get into a major issue like a few years ago, when we had Grape colaspis hit a lot of fields around Lee County, Monroe County. Where we saw growers lose their stand two or three times, well itÕs a good insurance to protect you getting a stand. ItÕll keep you out of trouble. I just think for the money itÕs really good. We see improved stands, improved emergence just like we do with rice, so I just think thereÕs a whole lot of value to the soybean insecticide seed treatments, absolutely.

I guess thatÕs about all we got today. I want to thank you for joining us on Arkansas Row Crop Radio. WeÕre out.



End notes: Arkansas Row Crops Radio is a production of the University of Arkansas System Division of Agriculture. For more information please contact your local county extension agent or visit uaex.edu.