Sorghum #2

(Jim) Good morning folks, welcome to that’s My Farm. I’m Jim Shroyer your host and we’re in luck because we’re on the Agronomy Farm here on the campus of K-State. And if you remember the last show, we had featured the Sorghum Field Day. Well, we’re in luck because we’re gonna continue the spotlight on grain sorghum. And so, get your cup of coffee, come on back and we’ll talk to some more researchers about grain sorghum production.Closed Captioning Brought to you by the Kansas Soybean Commission. The Soybean Checkoff, Progress Powered by Kansas Farmers.

(Jim) Good morning folks, welcome to That’s My Farm, I’m Jim Shroyer your host. And we’re in luck because we’re at the Agronomy Farm and we’re still talking about the Agronomy Field Day that we have. And last session we talked to Tesfaye Tesso our Sorghum Breeder here at
K-State and talking about some of the drought and cold tolerance that he’s developing. And Tesfaye, tell us a little bit more about some of the other aspects of your breeding program. I’m thinking about the sugarcane aphid. (Tesfaye) Like I mentioned earlier, the key focus of our breeding program was to enhance yield potential by developing materials that have enhanced traits that contribute to yield. (Jim) Sure. (Tesfaye) And then one other thing that has come up in recent years and was threatening sorghum production was the sugarcane aphid. We haven’t started any research on that one. And it was the first time that it showed up in our field basically, for the first time to see the insect. This year after we noticed that the insect was in the field we started scouting our materials, and as we do that we saw very significant differences between different lines between different hybrids in terms of sugarcane aphid infestation. (Jim) Right, right. (Tesfaye) One thing that was very interesting that we noticed was that there is an experimental hybrid that was planted next to one of the commercial hybrids that are on the market, this one. And this particular material was heavily infested by sugarcane aphid at that time. Probably the effect is visible. (Jim) Oh ya you can still see the damage. (Tesfaye) Yea. Standing next to that was an experimental hybrid that did not have a single insect on it. (Jim) And we’re only 30 inches away from the other one. (Tesfaye) Exactly. It was 30 inches away from the other one. Normally the insect attacks the lower part, the lower side of the leaf. This one did not have a single insect on it. This one carried tens of thousands of insects on it basically. So, we were very impressed. We didn’t make any effort to breed for sugarcane aphid resistance but this is what happened by chance. And I am not sure whether it is the male part or the female part of this hybrids that had the resistance in it. (Jim) So, now you gotta go back and look at the two inbreds. (Tesfaye) We go back. We know the pedigrees, where they come from basically. So we are going to explore that and then try to… (Jim) Well this basically tells you you’ve got genetic diversity for sugarcane aphid. (Tesfaye) Definitely. You know, it really sends a very big panic when it showed up and especially the rate with which it really invaded sorghum fields over the last couple of years. But when you look at your genetic resources that are already available, it is just going to be a matter of time to come up with hybrids that is good and that can also resist sugarcane aphid very well. So, that is a good genetic resource out there it looks like. (Jim) Tesfaye thank you for telling us a little bit about the sugarcane aphid resistance that you have here. I appreciate it. (Tesfaye) Thank you so much. (Jim) Folks, stay with us. We’ll be right back after these words from our sponsor.

(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer your host and with us we have Dr. Brian McCornack, he is a researcher in the Department of Entomology. Brian, we’ve been hearing about sugarcane aphids coming in and I guess we had a little bit late last year. So, kind of tell us…we’ve got lots of aphids so now we’ve got a new one. (Brian) Lots of new ones, all summer. (Jim) So, tell us about the sugarcane aphid. (Brian) Sugarcane aphid is actually a new pest for us in Kansas, like you said. Last year though we didn’t really get it until late August. And this year, our first reports of it were sumner, Sedgwick County, late July. But given the population size that we saw they’re most likely here early July, which means two months more here to feed and reproduce than they were last year. (Jim) OK. More time to do damage. (Brian) More time to do damage right. So we went from two counties infested last year to well over 20 this year. And even though we started at two counties this year and blew up within a few weeks time, simply because crops are at the stage, we have enough aphids coming in. This is a migratory pest so it’s not over wintering. Populations that are coming in on the same events as corn earworm. Coming from Texas and Oklahoma and making it to our doorstep. And also we went from very few to lots to have to manage within a few weeks time. (Jim) So, did the weather pattern obviously the winds from the south really helped, but did the moisture that we had in the summer and maybe cooler than normal really help as well? (Brian) Yea, I guess the cooler temperatures not so much. The cooler might have helped them slow down a bit. Actually, they are a warm season aphid. The green bug, they like the cooler temperatures, but sugarcane aphid likes the 90 to 100 degree weather. They’re more actively feeding, they’re sucking that plant dry, they’re reproducing more. They seem to thrive with it. Natural enemies don’t thrive at those hotter temperatures. So, when they cool down it might give natural enemies a chance to catch up. (Jim) Like the ladybugs. (Brian) Like ladybugs and lacewings. Now we’re seeing clouds of lacewings come out of that untreated sorghum. So natural enemies do well, but it’s a numbers game and timing. Looking at the difference between managing early season sorghum and late season sorghum. Early season you might of had two months to manage it. You’ve got a two week pre-harvest interval for the two products that we have, that we recommend, which are Transform and Sivanto. (Jim) We’ll talk more about those in a second. (Brian) Talk more about that. For a late season you have maybe three or four months to manage it. So, it becomes really important to scout early, scout often and know before you spray. That was our mantra this summer because these populations can change quickly. (Jim) OK. So, why is this critter so difficult to control and what damage does it cause? Those are two questions there. (Brian) So, the damage can be, what we call a physiological loss, so it’s sucking the nutrients dry. So, it’s see… (Jim) Like green bug. (Brian) …the energy that would have went into the seeds is now being removed. The other is mechanical. So, later season and late stage infestations and the aphids actually being in the heads at the time of harvest can cause the plants to be or the seeds to be sticky. And that’s where you’re saying… (Jim) That’s that honey dew. (Brian) The honey dew, yep. So, it’s a byproduct of the aphid. (Jim) Right. (Brian) So they’re creating that as they feed. (Jim) Right. (Brian) And that’s what’s been clogging the combines from Texas to Oklahoma. But for us it’s understanding where those populations are within the plant and how close they are to moving up into the heads. But most of what we see is physiological loss. (Jim) I want to talk a little bit about how difficult it is to control them and the reason for that, but we’ve got to take break. So, folks, stay with us, we’ll be right back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm and Brian McCornack didn’t run off during the break here. So, thank you Brian. (Brian) Thank you for that. (Jim) We talked a little bit about the physical yield loss. But what about difficulty in controlling it? They’re on the underside of the leaves. (Brian) That’s exactly right. (Jim) And they can be trapped in the boot as well, so we’ve got some issues here on controlling it. So, kind of tell us about that. (Brian) The biggest issue is coverage. So, we’ve got the product. So, we’ve got two products that we recommend in there we call translaminer, which means they need to come in contact with the leaf. The leaf needs to soak it up and then the aphids need to actively feed on it. (Jim) OK. (Brian) So if you spray the top leaves and you’re expecting to translocate, that’s not going to happen. It’s not going to move to other parts of the plant. Which is why you need good coverage of those two products. So Sivanto and Transform are the two that have been working in replicated field trials is the best. And that’s mainly because you don’t have to come into contact with the aphids, but you can come in contact with the leaf. Aphids feed on the leaf, they get the toxin and then they die. But if you don’t get good coverage in the canopy and they’re in the lower parts of the leaf earlier in the season… (Jim) Or on the lower part of the plant. (Brian) Lower part of the plant, yes. If you’re only using five by air, 20 by land. (Jim) We’re talking gallons. (Brian) As far as gallons per acre. And so that means you’re getting good coverage, but you need to get penetration down into the canopy where the aphids are, so you actually get good efficacy in your kill. (Jim) Right, right. So, what about other critters besides the sugarcane aphid? I mean we’ve got the corn earworm. (Brian) Corn earworm, sorghum head worm. And the thing is it’s moving on those same weather events. So, the likelihood of us dealing with the sugarcane aphid in the future is also going to co-exist with these corn earworms. (Jim) OK. (Brian) So, managing those in the long term, chances are it’s going to be managing that at the same time. (Jim) Well product-wise, you’re talking about these… (Brian) Products are different though. (Jim) That’s what I wanted to get to. (Brian) Yep products are different. So, typically we use pyrethroids and organophosphates and some others that work pretty well with the corn earworm. But if you’re using the same pyrethroids and organophosphates for sugarcane aphids you’re not getting contact, cause you need contact to kill them. (Jim) Right. (Brian) What you end up doing then is removing all those natural enemies that are on the leaves, cause they’re more susceptible to those pyrethroids and organophosphates, so you can then actually flair your aphid population by choosing the wrong product for your corn earworm. (Jim) I’ll be darn. (Brian) So if you put the corn earworm product in, but if you know you have to treat all those aphids then put your Transform or Sivanto in at the same time. (Jim) Otherwise you’re going with a pyrethroid, like you said, you’re going to take out the good bugs. (Brian) Take out the good bugs, yea. (Jim) You’re taking out the good bugs and we don’t want that. (Brian) Only the bad bugs kind of wreak havoc like you see here. This is a naturally infested field. Populations are beyond treatable levels. This is, luckily for us, an experimental plot. But documents within a few weeks time, populations can build to treatable levels. (Jim) Brian I really appreciate you taking time out between stops on field day here. (Brian) Absolutely, my pleasure. (Jim) And this is something that we’re really going to have to pay attention to in the future. (Brian) Absolutely. (Jim) Brian, thanks a lot. (Brian) Thank you. (Jim) Folks, stay with us. We’ll be back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer and we’re fortunate to have Dr. Curtis Thompson with us, our Extension Weed Scientist. And Curtis, we’ve been talking about this new technology in sorghum with herbicide resistance for a few years now. So, kind of give us a little update on this new technology, what it’s called and how it’s going to be used. (Curtis) Alright, well thanks Jim. It’s great to be with you. The new sorghum that has, we’ll call it an ALS-resistance gene is Inzen sorghum. (Jim) Inzen. I-N-Z-E-N. (Curtis) I-N-Z-E-N. (Jim) OK. (Curtis) That’s been branded by DuPont who now is the ownership of this technology. But several years ago of course, we developed it here at K-State. We were using Incorn, this was prior to the Roundup Ready Corn. We were using a product called Accent or Beacon to try to control shattercane in corn. And we were doing a good job up until resistance developed. (Jim) Sure. (Curtis) They were able to move the gene from this resistant shattercane into sorghum. (Jim) OK. (Curtis) And so now this Inzen sorghum technology, the main purpose of that is to allow us then to use one of the ALS grass herbicides okay, to be able to control grasses post emergence in sorghum. (Jim) Post emergence OK. (Curtis) Grasses have always been a problem in grain sorghum. So, we’ve depended on pre-emergence herbicides They can be very effective if we get timely rainfalls. But unfortunately sometimes it doesn’t rain. (Jim) No. (Curtis) And so grasses come up and it’s usually a lost case in grain sorghum. And so with this technology it will allow us to come in and spray post emergence on an Inzen sorghum hybrid, these annual grasses with this herbicide and hopefully get effective control. (Jim) OK, so let’s go back to the annual grasses, which ones are we talking about? Crabgrass? (Curtis) Well we’ve got several, crabgrass. And crabgrass is one of those that’s a little tougher. We’ve got to spray ’em when they’re small. (Jim) OK. (Curtis) Very small, we’re talking less than two inches. (Jim) Now how big’s the sorghum at this time? (Curtis) Well it depends on…I think we’re going to have to go based on weed size, more than sorghum size. (Jim) And it won’t hurt the sorghum. (Curtis) At this point we may see some slight yellowing in the sorghum, but it doesn’t seem to stunt it or slow it down and it doesn’t seem to be any kind of a yield drag. And so…but most important is to get these grasses when they’re small. (Jim) What other grasses besides crabgrass? (Curtis) Well we can do a good job on foxtails. That’s the giant foxtails, green foxtail, yellow foxtail. We have excellent control of barnyard grass. We’ve got good control of volunteer wheat. (Jim) Oh really? That’s good. (Curtis) Which is…a lot of time sorghum is planted after wheat. We do have volunteer out there and that happens to be one that will come through a lot of our pre-emergence products. And so this will allow us to clean up volunteer wheat. If we have shattercane in a field or Johnsongrass in a field that is ALS susceptible, we can get very good control. The problem is we’ve got probably too much ALS resistant shattercane around and so folks are gonna be unhappy if they use this technology and think they’re going to control shattercane and it’s ALS resistant. (Jim) We’ve got to take a break here. Just a second. Folks, stay with us, we’ll be right back after these words from our sponsors.

(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer. We’re at the Agronomy Farm still talking sorghum at the Sorghum Field Day. We have Dr. Curtis Thompson with us on this last segment. And we were talking about Inzen sorghum and that ALS-resistant gene that’s in it. What’s the chances, the possibilities of that jumping to shattercane or Johnsongrass? You mentioned there’s already the population out there. (Curtis) Remember the gene came from shattercane. (Jim) Exactly. (Curtis) And so a cross was made from shattercane on to our sorghum lines. And in fact, the gene will return to shattercane just as simply. And so that does mean that we do have to do some stewardship practices to try to prevent the gene from flowing from this field into the wild populations. That maybe means you have to look around your field and find out whether or not you’ve got sorghum relatives adjacent that maybe need to be mowed down so that no seed is produced. I think on the label they’re going to prohibit planting sorghum after Inzen sorghum because we always have volunteer, which we have to be able to manage. (Jim) OK. (Curtis) And so it’s gonna…I mean there are some things that we do have to do to try to prevent the gene from moving to the wild population. Because we know it can. (Jim) Right, right. So this isn’t a silver bullet for all post emergent grass issues. We still have to think about pre-emergent as well. (Curtis) Absolutely. This is a tool in the tool box, but we’re still gonna be recommending that a pre-emergence product be used that gives you grass and broadleaf weed control. (Jim) An example of that; what would be a good one? (Curtis) Well, a good example is if I use the chemical name, let’s say as metolachlor in atrazine, or it might be dimethenamid and atrazine. You know the chloroacetamide group of herbicides with atrazine will really help out on grasses and gives us some broadleaf weed control. (Jim) Right. (Curtis) We have way too many resistant broad leaf weeds, in other words that are ALS resistant, so we do have to depend on other chemistry to manage broadleaf weeds. (Jim) OK, so we were talking about a pre-emerge and we’re talking about this Inzen, using this as a post emerge. But then we have the broadleaf, so you’re talking about, at the same time of using the post emerge grass, that we’re talking about putting a post emerge broadleaf herbicide in there as well? (Curtis) And it’s gonna depend on the broadleaf species that you have available to you. But if you’re out west and you have kochia, yea we’re going to have to have a dicamba-type product in the tank with Zest in order to get kochia control, because otherwise we won’t control it with just Zest. If we have pigweeds, it might be 2,4-D that we have in the tank. So, yea, there’s gonna have to be some other broadleaf component if there’s broadleaves present at the time of the application. (Jim) Curt, appreciate you taking time to talk to us this morning. (Curtis) Pleasure to be with you Jim and pleasure to be with That’s My Farm. (Jim) OK. Folks, thanks for being with us on this session of That’s My Farm. And don’t forget, this time next Friday, we’ll have another show of That’s My Farm. See you then.

Closed Captioning Brought to you by the Kansas Soybean Commission. The Soybean Checkoff, Progress Powered by Kansas Farmers.

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