8 minute read
Protect Your Crop From LCB
Scout plants, pegs and pods for this yield-robbing insect.
By Amanda Huber
It’s the No. 1 most destructive insect pest of peanuts in the Southeast, says Mark Abney, University of
Georgia Extension entomologist. Lesser cornstalk borers thrive in hot, dry conditions, a weather pattern usually found at least some point during most peanut-growing seasons.
Scout For Trouble
LCB’s prime activity period generally begins in June and continues through the summer months.
Larvae feed above and below the soil line and can kill newly emerged seedlings, destroy pegs and developing pods, damage plant crowns and weaken plants that survive. Wilting is one of the earliest signs of LCB infestation. Withered buds, stunting and plant deformities are also common.
“You will usually see lessers in the driest spots in the field first,” Abney says. “Look for plants that are wilted and/or have skips beside them and plants at the ends of rows. Checking these areas first can save a lot of scouting time. If the larvae are not here, they are not likely to be in other parts of the field.”
The presence of moths may be the first sign LCB is in the field. A single moth will lay from 100 to 200 eggs near the soil surface. After hatching, larvae live in the soil and construct tunnels from soil and bodily fluids tightly woven together with silk. These silken tubes are often found more than the insect itself. Larvae leave the tubes to feed at the base of the plant.
“Look for wilted stems and silk tubes, remove plants and check tap root, pods and stems for feeding injury and larvae,” Abney says. “They are not always easy to find.”
Silken tubes on pegs are a sign of LCB.
Weather Plays A Role
Producers may want to take a waitand-see approach early in the season when LCB populations are low, but as pegs and pods are developing, that is the time to protect the crop from feeding.
“Scout and spray when the pest is present. If LCB populations get out of control in a field, it will be difficult to reign them back in. If you do not have LCB in your fields, there is no reason to apply a preventative insecticide.”
During those times when hot, dry conditions prevail, LCB pressure could be greater.
“Rainfall will help slow population growth, and we do not usually see LCB problems under pivots when adequate water is being applied. It is important to scout young peanuts under pivots as
Two spotted spider mite infestation on untreated peanut.
Two spotted spider mite infestation on peanut 14 days after a bifenthrin application.
Another pest found during drought is the two spotted spider mite, a tiny pest that spells big trouble.
“The most important factor leading to spider mite infestations in Georgia peanuts is drought, and we can’t do anything about that. The second most common factor is the use of a pyrethroid insecticide,” Abney says.
Again, scouting is needed to spot a problem before it gets out of hand. A spider mite outbreak can simply look like drought-stressed plants. If the crop is drought stressed, special consideration of insect management problems is needed so as not to exacerbate problems.
“Do not apply a pyrethroid insecticide to drought-stressed, non-ir
rigated peanuts without discussing the application with your county agent or consultant first. Pyrethroids will flare mites,” he says.
Producers should watch fields for signs of mite infestations, which usually show up around field margins and move inward as numbers increase. It is possible to spread mites across a field or from field to field with tractors and spray equipment.
Options for managing mites are few, and irrigation may be the best defense.
“If a field is less than 10 days from digging, I might consider using bifenthrin for spider mites in peanut. Otherwise, I would not.” Abney says growers should scout all non-irrigated fields for mites, but prioritize any fields where a pyrethroid was applied in the past six weeks.
these fields will probably not be getting irrigated enough to keep the pest at bay.
“We do not want to see crown damage occurring in young irrigated peanuts. Once the water needs of the peanuts ramp up, vines lap the row middles and pivots are running full steam, LCB should become rare in adequately irrigated fields,” he says.
Protect Pegs And Pods
The three UGA-recommended insecticides for LCB are chlorpyrifos, chlorantraniliprole and novaluron.
Abney says chlorpyrifos is applied as a granular product banded over the row.
“It requires rainfall or irrigation for activation, and applications are often followed by outbreaks of caterpillars and/or mites.”
The other two, chlorantraniliprole (Prevathon) and novaluron (Diamond), are applied as broadcast foliar sprays. However, Abney reminds producers that when using foliar insecticides, the product must reach the target.
“I would not spray for LCB with less than 15 gallons of water per acre; 20 gallons would be better.”
Additionally, he says while LCB does not survive well in moist conditions, one or two rainfall events will not eliminate an established population, and it is not
Larvae feed above and below the soil line and can kill newly emerged seedlings, destroy pegs and developing pods, damage plant crowns and weaken plants that survive.
likely possible to irrigate LCB away prior to row closure.
The bottom line for insect management at this point in the season will always be to scout for the pest and treat as needed to protect the growing peanut pods. PG
Virtually There
Industry groups adjust to meeting online, hope for added participation.
By Amanda Huber
‘‘ T he show must go on!” This was the cry of the circus ringmaster in his fancy coat and top hat to the crowd of spectators. Performing with live animals or carrying out daring acrobatics high above the big top often led to mishaps briefly stopping the action. That is when the ringmaster stepped in to say the show would continue.
COVID-19 is more than a mishap, but the peanut industry has adapted by announcing some summer meetings, USA Peanut Congress and the American Peanut Education and Society Meeting, will be held virtually.
Presentations And Panel Discussions
American Peanut Council executive director Patrick Archer says, “We are happy that all of our planned presenters will be available to do their presentations via webinar. These presentations will include panel discussions on how the industry is addressing the issue of aflatoxin and how marketers are adapting under the COVID-19 pandemic.”
Registration with an email address is required for Peanut Congress. Participants will receive log-in credentials prior to the event start date.
“The virtual congress is free to all American Peanut Council and American Peanut Sheller Association members and provides an opportunity for those members who have not attended lately to see what they’ve been missing,” Archer says.
The virtual meeting will be held June 15-16, 2020, with general session webinars I and II on Monday, June 15, and general session webinars III and IV scheduled on Tuesday.
For information or to register, visit www.peanut-shellers.org and click on the “Events” tab and then on “Peanut Congress.”
Zoom And YouTube
Another meeting going virtual this summer is the annual gathering of peanut researchers.
APRES President Barry Tillman says, “For the first time in our 51-year history, the annual meeting of the American Peanut Research and Education Society will not be held face to face.”
However, peanut researchers will not be defeated by COVID-19 for their 52nd yearly convention.
“Instead of canceling the meeting, the program committee and board of direc
Donate Your Dinner To Support Peanut Proud
A traditional event at Peanut Congress is a fundraiser for the American Peanut Shellers Association Political Action Committee. In light of COVID-19, the APSA PAC instead asked participants to “Donate Your Dinner.” By purchasing a PAC ticket for $175, APSA will donate 175 jars of peanut butter to Peanut Proud, the peanut industry’s non-profit humanitarian organization.
A donation form can be found on the APSA website at www.peanut-shellers.org by clicking on the “Events” tab, then on “Peanut Congress.”
tors decided to conduct a virtual meeting. Part of the meeting will be webinars through Zoom and others will be prerecorded scientific presentations hosted on our YouTube channel.
“While this is new territory for APRES, I am confident in the leadership of the local arrangements and technical program committees, and I believe we will have a great meeting,” he says.
The first general session — production, challenges and strategies — and a symposium on aflatoxin and drought tolerance will be as webinars, July 14. The Joe Sugg Graduate Student Competition and graduate student seminar webinars will be held July 15. All other presentations, research and education breakout sessions and posters will be prerecorded and hosted on the APRES YouTube channel. Year-end awards will be announced July 16, and a recognition ceremony will be held at the 2021 annual meeting.
“Special thanks to Gary Schwarzlose, program chair and president-elect, and John Cason, local arrangements committee, and their team for the leadership and flexibility to make the 2020 APRES virtual meeting possible. This is a great opportunity for colleagues who have not been able to attend recently to tune in to APRES 2020,” Tillman says.
For more information, visit https:// apresinc.com. PG
Southern Peanut Growers Conference july 16-18, 2020
