Spider Mites Inhabiting Drought-Stressed Soybean Fields

Two-spotted Spider Mite

Very dry conditions are encouraging two-spotted spider mites to lay claim to drought-stressed soybean plants throughout the much of the eastern Corn Belt.

When left untreated, spider mites can cause extensive and irreversible damage to soybean foliage, so growers need to keep an eye on their fields – especially if the weather remains dry.

“Mites are found in every field, every year, and usually do nothing of consequence to producers” said Christian Krupke, Purdue Extension entomologist. “However, stressed plants actually provide a more nutritious feast for spider mites than healthy plants do.”

Amino acids are more available to insects when they feed on stressed soybeans instead of healthy soybeans, he said. That means the mites can use these nutrients to synthesize proteins for use in reproduction.

“Under conditions where drought-stressed plants are abundant, mites thrive and quickly colonize large areas or fields where stress is more evident,” Krupke said.

Spider mite damage is typically most visible at first in the most stressed areas of the field; this often includes field edges. Soybean growers are likely to first notice foliar damage in the form of subtle stippling of leaves, which can progress to bronzing.

If dry weather persists and mites are left unchecked and untreated, necrosis, or tissue death, can occur. Once foliage is bronze, the damage is done and cannot be reversed, even with treatment, Krupke said.

But before growers consider treatment, he said, they need to be sure crop damage is a result of spider mite feeding and not one of the many other diseases, pathogens or nutrient deficiencies that can cause similar foliage appearances.

“To confirm the presence of mites, shake some discolored soybean leaves over a white piece of paper,” Krupke said. “Watch for small, dark specks moving about on the paper. Also, look for very tiny, fine webbing on the undersides of the discolored leaves.

“Once spider mites have been positively identified in the damaged areas of the field, it is essential that portions of the entire field be scouted to determine the limits and range of infestation.”

According to Krupke, spider mites colonize fields in a patchy fashion that often begins at field borders. He suggested sampling at least five areas of a field to determine how far mites might have moved into the field.

If mites are positively identified in drought-stressed soybean fields, Krupke said, pesticide application is typically warranted, and it sometimes takes more than one insecticide or miticide treatment.

“Surviving spider mites are able to repopulate a field much more quickly than their natural predators, which are usually also wiped out by these chemical applications,” he said.

Recommended pesticides include dimethoate and chlorpyrifos.

An even better “control” method, Krupke said, would be precipitation.

“Obviously, the best plant stress reliever under dry conditions is rain,” he said. “Significant rain doesn’t control spider mites but helps the soybean plant become more vigorous and healthy. This, in turn, makes the ‘juices’ of the plant less nutritious to the mites, and makes mites less likely to reproduce as quickly.

“We can’t make it rain, but we can take steps to make sure that mite scouting and treatment is prioritized until conditions improve. Mites don’t need to reach outbreak levels, but vigilance is important in early stages of infestation.”

Topics:

Leave a Reply

Insecticides Stories

Soybean aphid leaf
InsecticidesMulti-state Research Reveals IPM Best Option for Treatment of Soybean Aphids
May 17, 2017
About 89.5 million acres of soybeans will be planted across the U.S. in 2017 — a record high, according to Read More
Lygus pratensis
Crop InputsCalifornia Agriculture: What A Difference A Year Makes For Insect And Disease Control
April 3, 2017
“We finally got the rain,” David Haviland, Entomology and Pest Management Farm Advisor with the University of California Cooperative Extension, Read More
Golden Harvest Corn healthy leaves
Crop InputsFMC Emerges as DuPont Crop Protection Business Buyer, Becomes 5th Largest Ag Chemical Company
March 31, 2017
FMC Corp. and DuPont today announced the signing of a definitive agreement for FMC to acquire the portion of DuPont’s Read More
Soybean Closeup
FungicidesNew CROSSOVER PRO Formulation Offers Insect and Disease Control
March 29, 2017
INNVICTIS CROP CARE, LLC has launched CROSSOVER PRO as a first of its kind formulation combining propiconazole and lambda-cyhalothrin for Read More
Trending Articles
Migrant farm workers
LegislationTrump: Immigration Crackdown Won’t Impact U.S. Agriculture
May 16, 2017
President Donald Trump said he would seek to keep his tough immigration enforcement policies from harming the U.S. farm industry Read More
AGCO Ratliff featured
Eric SfiligojRemembering Robert Ratliff
May 15, 2017
With all the fast-paced happenings in agriculture this spring, with multiple mergers in the works and planting season in full Read More
Case sprayer nozzle closeup
EquipmentSpray Application: A Nozzle Renaissance
May 2, 2017
If you had asked four-decade ag veteran Mark Bartel, President of Wilger Inc., just a few years ago what lay Read More
ManagementWashington Update, Dow-DuPont Earnings, and the Passing of an AGCO Legend
April 27, 2017
Editors Paul Schrimpf and Eric Sfiligoj talk about the latest Beltway news, crop protection company 1st quarter numbers, and the Read More
Crop InputsFlying Under the Radar No More, FMC Goes Big
April 13, 2017
Describing FMC as “under the radar,” admittedly, is probably a stretch. But in a snap of the fingers, FMC upped Read More
Young Corn Plants
Crop NutritionStill Hunting Yields
April 1, 2017
There’s no denying it — the agricultural marketplace today is undergoing a fundamental shift in fortunes. Not too many years Read More
Latest News
Food IT Fork-to-Farm
Precision AgThe Mixing Bowl Event Connects Technology, Food, and Ag…
May 24, 2017
For the fourth consecutive year, The Mixing Bowl presents FOOD IT, under the theme “Fork to Farm.” Action-oriented entrepreneurs, industry Read More
Photo credit: The United Soybean Board/The Soybean Checkoff.
Seed/BiotechKansas State University Researchers Find New Pathogens …
May 24, 2017
A single seed seems so simple. Put it in the ground, give it some care, and you’ve soon grown food. Read More
Soybean Field
HerbicidesNew Dicamba Herbicide Premix Coming Soon from Syngenta
May 24, 2017
Syngenta has announced the name of its new herbicide featuring the active ingredients of S-metolachlor and dicamba. Upon registration by Read More
Eric SfiligojMonsanto ‘Picks Its Battles’ by Nixing Deere Deal
May 23, 2017
Having been in the trade journalism game since the mid-1980s, I remember several watershed moments during my career. One of Read More
FungicidesSyngenta Launches New Seed Treatment Fungicide
May 22, 2017
Syngenta has announced the launch of PLENARIS seed treatment fungicide for the control of downy mildew in sunflower. PLENARIS contains Read More
Corn close up
Crop InputsMonsanto’s First HPPD Herbicide Garners EPA Appro…
May 19, 2017
Monsanto announced today that EPA has federally approved Harness MAX Herbicide, the first herbicide in the Monsanto portfolio to provide Read More
ManagementPrecision Planting Deal, China Developments, and Enviro…
May 18, 2017
Editors Eric Sfiligoj and Dan Jacobs discuss the latest news on John Deere’s now dead deal for Precision Planting, China’s Read More
Soybean aphid leaf
InsecticidesMulti-state Research Reveals IPM Best Option for Treatm…
May 17, 2017
About 89.5 million acres of soybeans will be planted across the U.S. in 2017 — a record high, according to Read More
GROWMARK-2017-Interns
CropLife 100GROWMARK Names 2017 Summer Interns
May 16, 2017
Forty-two college students are exploring agricultural career opportunities this summer as GROWMARK interns. They are working at FS member cooperatives Read More
Migrant farm workers
LegislationTrump: Immigration Crackdown Won’t Impact U.S. Ag…
May 16, 2017
President Donald Trump said he would seek to keep his tough immigration enforcement policies from harming the U.S. farm industry Read More
Flooded corn in Indiana
FertilizerBoth Wet and Dry Conditions Threaten Nitrogen Loss
May 15, 2017
The weather is notoriously unpredictable, leading to challenges for planting, harvesting and applying the nitrogen (N) your corn crop needs. Read More
farmer Kip Tom
Precision AgAg Tech: On the Cusp of Something Big?
May 15, 2017
The investment and ag-tech sectors’ continuing courtship of agriculture, smoldering for three or four years now, was well in evidence at Read More
AGCO Ratliff featured
Eric SfiligojRemembering Robert Ratliff
May 15, 2017
With all the fast-paced happenings in agriculture this spring, with multiple mergers in the works and planting season in full Read More
Greg Musson, Gar Tootelian
ManagementOpinion: Shaking Your Perspective in Ag Retail
May 12, 2017
Some of you I’m sure have encountered our recently retired salesman extraordinaire, Dan Bellanger. He worked in the industry for Read More
Exterior view of CPS Big Lake facility which includes enclosed receiving and load out area
CropLife 100New Alternative Weed Resistance Traits Could Experience…
May 12, 2017
It wasn’t too many years ago that ag retailers and their grower-customers could hardly wait for new options to fight Read More
Diane Allemang and Dan Jacobs
Crop InputsFMC Agricultural Solutions, Casa Pacifica Partner to He…
May 11, 2017
FMC Agricultural Solutions is teaming up with Casa Pacifica Centers for Children and Families, an organization that supports vulnerable children Read More
UncategorizedWhat’s Up With ARA
May 11, 2017
CropLife Editor Eric Sfiligoj talks with Brian Reuwee regarding what issues are on the docket for the Agricultural Retailers Association. Read More
BASF Maglis tablet retailer grower
Precision AgQ&A: What BASF’s Latest Foray into Precision …
May 11, 2017
In late April, BASF agreed to acquire U.S. precision ag player ZedX, a leader in the development of agronomic weather, Read More