Where It’s Dry, Pest Concerns Are High

Not everyone’s dealing with wet fields. In areas where dry conditions have plagued soybean crops, some pests have been having a field day even this late in the season, and Extension specialists say there are steps retailers and their growers should take.

The key pests at this stag in such areas as Ohio and Kentucky are two-spotted spider mites, bean leaf beetles, and soybean cyst nematodes.

  • Two-spotted spider mitesbecome active when fields are dry, and in Ohio, Ohio State University Extension entomologists have reported some outbreaks, especially along field edges. The two-spotted spider mite feeds on the sap of the soybean plant causing injury. Large spider mite populations, running in the tens of thousands per plant, are enough to kill the crop, causing significant yield losses.

     

    “We continue to think that they will not become whole field infestations, although growers should nevertheless check areas within their fields,” says Ron Hammond, an OSU Extension entomologist. “This is especially important on late-maturing soybeans that were planted late and are still green. Those fields that are starting to yellow are probably past the stage where spraying for mites would be recommended.”

    Yellow/bronze discoloration of plants along field edges or within in a field is characteristic of spider mite feeding. “If growers are finding large populations of adults and eggs on the underside of the leaflets, then treatment is probably warranted,” he says. “If mites have built up sufficiently along the field borders, growers should make an edge spray. This should give late-planted soybeans enough time to continue to make good yields.”

 

  • Soybeans grown for seed, especially late-planted or late-maturing beans, should be monitored for bean leaf beetledamage as leaves begin to yellow and pods remain green, say Purdue University entomologists.

    Bean leaf beetles scar the surface of pods, but only occasionally feed through the pod to the developing beans, explains John Obermeyer, Purdue Extension integrated pest management supervisor, and Larry Bledsoe, Purdue Extension pest management expert. During pod maturation, this scar often cracks leaving an entry hole for airborne plant pathogens that may cause discolored, moldy, shriveled, or diseased beans that show no outward signs of the pathogen.

    Bledsoe says it’s important for pest managers to be able to predict whether economic damage will occur based on the types and numbers of beetles that are present and the stage of pod development (i.e., green, yellow, yellow-brown, or brown pods). Once the pods turn yellow to yellow-brown, they become less attractive and less susceptible to damage. Control is normally not warranted from this point on.

    Obermeyer and Bledsoe recommend randomly selecting two plants from five different areas of the field and then counting the number of pods per plant and the number that show damage. Calculate the percentage of damaged pods per plant for the field as a whole. Note if the pods are green, beginning to turn yellow, or are yellow/brown. Also determine the number of beetles per sweep using an insect sweep net. Take five sets of 20 sweeps in the field. Determine the number of bean leaf beetles per sweep. Additionally, note whether beetles are still actively feeding while surveying the field, they advised.

    There has been considerable interest in bean leaf beetle and its association with bean pod mottle virus (BPMV). Bean leaf beetle is one of major beetle-vectors of this disease. They spread the virus by feeding on infected plants, ingesting the virus with plant tissue, and then regurgitating gut content after moving to and feeding on an uninfected plant. BPMV symptoms at harvest include green stem and hilum bleeding. Treatment for bean leaf beetle to reduce bean pod mottle virus this time of the year is not recommended, as most disease transmission occurs very early in the season.

  • Soybean cyst nematode (SCN)also does damage to soybeans under drought stress. Deemed the “silent robber of yields,” soybean cyst nematodes feed on the roots of young plants, which prevents the roots from taking up vital nutrients. The result is a drop in yields and subsequent economic losses.

     

    Anne Dorrance, a plant pathologist with the Ohio Agricultural Research and Development Center, urges growers to scout their fields for potential SCN populations.

     

    “Where the soybeans are shorter and have fewer pods is a great place to check for SCN on the roots,” said Dorrance, who also holds an OSU Extension appointment. “Dig up the soybeans and shake off the soil, then look for the females. They appear as tiny white pearls, which glisten on the roots.” Notes should be taken and those fields should be sampled in the fall for egg counts through laboratory tests.

     

    “A good accurate egg count in the fall is the first step in soybean cyst nematode management,” said Dorrance. “The best management practice is crop rotation, crop rotation, crop rotation. Once the insect is present, you can’t get rid of it.”

Topics:

Leave a Reply

Insecticides Stories

Soybean Field
InsecticidesDiflumax 2L Insect Growth Regulator Receives EPA Section 3 Registration
September 8, 2016
HELM AGRO US, Inc. has announced the EPA Section 3 registration of its new Diflumax 2L Insecticide/Miticide. Containing the active Read More
Soybean Field
InsecticidesZeal SC Miticide Now Registered For Soybeans
August 9, 2016
Valent U.S.A. Corp. has announced the EPA registration of Zeal SC Miticide for soybeans. Zeal is a proven residual miticide Read More
Syngenta plant
InsecticidesGrowers, Distributors May Use Remaining Stocks Of Belt Insecticide
August 1, 2016
The U.S. EPA’s Environmental Appeals Board (EAB) has upheld an earlier EPA decision to cancel registration for Bayer’s insecticide flubendiamide, Read More
InsecticidesSyngenta: Beware Of Early Stinkbug Threat To Soybeans
July 28, 2016
With the record warm temperatures this past winter and confirmations from early entomologist reports, Syngenta encourages growers to monitor stinkbug Read More
Trending Articles
Bayer Monsanto
Crop InputsBayer-Monsanto Mega-Merger: 6 Things You Need To Know
September 14, 2016
Mega mergers have become almost routine in the agricultural industry. Right on the heels of Monday’s news that fertilizer giants Potash Read More
Potash Corp Agrium
Crop InputsAgrium, Potash Corp To Merge To Create $36 Billion Company
September 12, 2016
Canada’s Agrium Inc. and Potash Corp of Saskatchewan Inc. have agreed to combine in a deal that would create a Read More
Osage Co-op Elevator Osage, IA Finished Building
OpinionAre We Crazy?
September 8, 2016
At some point in the first few months of my employment here at CropLife® magazine, I started getting curious about Read More
ManagementMAGIE 2016 Highlights and Deere Anti-Trust
September 1, 2016
CropLife Editor Eric Sfiligoj discusses the recent Midwest AG Industries Exposition and the Department of Justice’s objection to John Deere Read More
ASMARK 2016 Retailers Live! Tour - CPS
CropLife 100CPS Acquires Texas Retail Operation
August 23, 2016
Crop Production Services (CPS) has acquired the assets of Larry’s Chemical and Spray, Inc., for an undisclosed amount in an Read More
Key Cooperative Marcus Construction Steel Building
Retail FacilitiesMarcus Construction Builds High-Speed Agronomy Center For Key Cooperative
July 7, 2016
Key Cooperative in Grinnell, IA, wanted a state-of-the-art Agronomy Center to better serve its customers. Marcus Construction delivered exactly that. Read More
Latest News
Syngenta Seedcare Institute
Seed/BiotechSyngenta Opens New North America Seedcare Institute In …
September 23, 2016
Syngenta unveiled its new Seedcare Institute in Stanton, MN, during a recent grand opening celebration. More than 150 industry leaders, Read More
StewardshipMonsanto Invests $1.6 Million In System To Quantify Gre…
September 23, 2016
The USDA – Natural Resources Conservation Service (USDA-NRCS) recently awarded the National Corn Growers Association (NCGA) and its Soil Health Read More
Pipe rack
LegislationCourt Sides With Ag Retailers On PSM
September 23, 2016
The D.C. Court of Appeals has ruled the Occupational Safety and Health Administration violated the Occupational Safety and Health Act when Read More
ManagementPacific Coast Fertilizer Announces Interest In Longview…
September 22, 2016
Pacific Coast Fertilizer LP (PCF) announced at the Cowlitz Economic Development Council board of directors meeting its interest in developing Read More
Young corn plants in soil
UncategorizedCool Planet Raises Additional $9 Million To Commerciali…
September 22, 2016
Cool Planet has announced the first close of a new financing round to commercialize the company’s Cool Terra Engineered Biocarbon Read More
Crop InputsJim Loar Promoted To President And CEO Of Cool Planet
September 22, 2016
In a move that reflects and reinforces the company’s commitment to the agricultural market, the Cool Planet board of directors Read More
BlendersNorth Dakota Coop Debuts Dry Fertilizer Plant
September 22, 2016
North Central Grain Cooperative has begun operations at a new dry fertilizer plant at its Rolla, ND, site. It is Read More
Crop InputsMonsanto, Bayer Officials Defend Proposed $66 Billion M…
September 21, 2016
Top officials for Monsanto and Bayer defended their proposed $66 billion merger before skeptical senators on Tuesday, insisting that the Read More
ManagementUpcoming Shows & Recent Events
September 19, 2016
Editors Paul Schrimpf and Eric Sfiligoj talk about upcoming trade shows and events and review the Mid America CropLife Association Read More
Industry NewsVerdesian Life Sciences Appoints New CEO
September 19, 2016
Verdesian Life Sciences, a plant health and nutrition company, today announced that its board of directors has named Kenneth M. Avery Read More
Corn
Crop InputsEPA Settles With Syngenta For Alleged Multi-Regional Pe…
September 19, 2016
The U.S. EPA has announced a multi-region settlement with Syngenta Crop Protection, LLC (Syngenta) in Greensboro, NC, for alleged violations of Read More
ManagementMerger Mania
September 16, 2016
Editors Paul Schrimpf and Eric Sfiligoj discuss this week’s mega-ag mergers of Bayer and Monsanto and Potash and Agrium. Read More
Monsanto sign
Crop InputsMonsanto Ends Up Being A Bargain For Bayer
September 16, 2016
History will say Bayer got a bargain in its $66 billion purchase of Monsanto, writes David Nicklaus, St. Louis Post-Dispatch. The Read More
Greg Musson, Gar Tootelian
CropLife 100California Ag Retailer Steps Up To Feed Families Affect…
September 16, 2016
GAR Tootelian, Inc. (GAR) in Reedley, CA, is challenging the Central Valley to help raise enough money and provide 525,000 meals Read More
Crop InputsBayer, Monsanto CEOs Discuss Merger
September 15, 2016
Werner Baumann, Bayer CEO, and Hugh Grant, Monsanto CEO, discuss why they decided to merge their companies. Read More
Corn close up
Crop InputsNY Times: Bayer-Monsanto a Bad Deal for Farmers
September 15, 2016
Via NY Times: Don Halcomb, a 63-year-old farmer in Adairville, KY, is expecting his profit to vanish this year, largely Read More
Werner Baumann, Bayer AG, and Hugh Grant, Monsanto
Crop InputsBayer-Monsanto Merger Creates New Global Ag Giant
September 14, 2016
During the whole of 2016, many of the companies that do business in the agricultural industry have concluded the best Read More
Bayer Monsanto
Crop InputsBayer-Monsanto Mega-Merger: 6 Things You Need To Know
September 14, 2016
Mega mergers have become almost routine in the agricultural industry. Right on the heels of Monday’s news that fertilizer giants Potash Read More