Insect And Disease Report

Sudden Death Syndrome Soybeans

Trying to predict this year’s insect and disease problems based on last season’s experiences can be a little dicey, as always. But experts are reading some signals that make them more optimistic about corn than soybeans.

Soybean Safety Questions

Indiana saw ideal planting conditions for soybeans in April, but cool, wet weather in May led to seedling blights and favored development of sudden death syndrome (SDS), says Kiersten Wise, plant pathologist with Purdue University. Some fields experienced serious yield losses. In fact, SDS was also widespread and severe in Iowa, Illi­nois, Minnesota, Wisconsin and South Dakota according to Extension plant pathologists in those states. Foliar symptoms of the disease were especially abundant in fields planted in April in Illinois and Indiana.

Wise also warns that Midwest fields with high levels of white mold of soybean in 2009 — planted back to the crop in 2011 — may be in danger. “We are concerned about the potential for disease development if the weather around flowering is cool and wet,” she says.

Resources Plentiful

Midwest universities offer a host of helpful tools for tracking pests in fields. Some publications that specialists recommended to us included:
•  “Soybean Diseases” from Iowa State University is a new comprehensive gathering of soybean disease and management information.
•  The “Purdue Pest & Crop Newsletter” helps growers and dealers scout fields and keep track of insect and other pest problems across Indiana. It’s available as a PDF sent weekly to subscribers.
•  The “Crop Observation and Recommendation Network Newsletter” (C.O.R.N.) offers current pest reports and can be found at http://agcrops.osu.edu.
•  A new online map to track the presence of South­ern corn rust and soybean rust in the U.S. is available at www.ipmpipe.org.

Carl Bradley, plant pathologist and Extension specialist with the University of Illinois, noted that charcoal rot hit Illinois, particularly to the south where very dry conditions prevailed. And soybean cyst nematode continued to rob yield from growers who are ignoring or mismanaging the pest, he says.

Growers across Illinois saw frogeye leaf spot, though generally not at damaging levels. But Bradley reports that strobilurin fungicide-resistant strains of this fungus were actually confirmed in Southern Illinois, as well as in Western Kentucky and Western Tennessee. “So it’s important that growers with a history of damaging levels of frogeye leaf spot manage the disease through resistant varieties rather than spraying a strobilurin fungicide,” he recommends.

Aphids Have New Friends

As Mike Gray, professor with the University of Illinois, puts it: “Last year was very unimpressive for major insect pest infestations of corn and soybeans throughout many areas of the Midwest.” Soybean aphid densities were very low — and are anticipated to be low again this season, he says. In fact, Gray says it will take almost ideal environmental conditions (mild summer) to promote outbreaks, and even if they occur, it will be late in the season.

Greg LaBarge, Extension educator with The Ohio State University in Northwest Ohio, does note that based on the every-other-year guideline for soybean aphid infestations, 2011 is an “on” year.

Gray says there are a few other insects to watch for in 2011. Some new stink bug species, including marmorated, red-banded and red-shouldered stink bugs, appear to be making their way across the Corn Belt.

Ron Hammond, field crop Extension and research entomologist with The Ohio State University, reports that brown marmorated stink bug has now been seen throughout Ohio. He anticipates this pest will increase in numbers and be a possible problem on soybeans in 2011. Erin Hodgson, entomologist at Iowa State University, explains that this stink bug punctures plant tissues such as leaves and stems and sucks on plant juices with its beak, similar to aphids or leafhoppers.

Turning To Corn

In corn, high levels of gray leaf spot (GLS) hit some fields in Indiana, reports Purdue’s Wise. “If these fields stay in reduced-tillage and continuous corn rotations, there is the potential for GLS to be more severe if the weather conditions are favorable for disease development,” she cautions.

GLS also caused damage in Illi­nois, as did Northern leaf blight, says Bradley. Unfortunately, some growers’ fields suffered major losses from Goss’s bacterial wilt. Hardest hit were fields that had suffered injury from earlier in the season, such as wind or hail damage. Goss’s wilt also caused damage to crops in parts of Iowa.

Ear rots, especially Diplodia ear rot, were seen in some areas that had sustained heavy rainfalls prior to and throughout silking, says Bradley, and stalk rots occurred in some areas, especially in fields that had severe leaf blights from gray leaf spot or Northern leaf blight.

Last season raised questions for Bradley about the effectiveness of corn hybrids with Northern corn leaf blight resistance. “In some cases where growers felt the resistant hybrids were not performing like they should, it’s possible a different race of the fungus was present,” he says.

Corn Feeders

Western bean cutworm (WBC) hit many Indiana fields in 2010, and “we would expect high numbers again this year, given the good overwintering conditions,” says Christian Krupke, entomologist at Purdue University. Risk factors include sandy soils, no-till fields and continous corn.

Krupke says scouting combined with pyrethroids applied at egg hatch achieve excellent control levels, as do Bt hybrids labeled specifically for WBC. The egg-laying period for this cutworm is from mid-June to mid-July, so that’s when scouting and/or treatment should occur, says Krupke. Once the WBC larvae enter the plant, they are not vulnerable to sprays.

Extension specialists are, in fact, tracking the eastward progress of this pest, says northwest Ohio State’s LaBarge. He’s seen some noneconomic feeding injury, but does not anticipate problems in his region in 2011. He’ll be paying closer attention to trap counts and corn growth stages.

There is some seriously good news on other corn insects: West­ern corn rootworm densities were some of the lowest Illi­nois’ Gray has seen in 20 years. Here again, it will take very favorable spring conditions (early planting, drier soil conditions in late May and early June) during hatch for them “to mount any kind of rebound.”

Krupke found the same kind of rootworm numbers in Indiana. “They were virtually absent in many fields where they were abundant just a few years ago,” he says. He credits a combination of Bt corn adoption and extremely wet springs that have drowned larvae.

Even more good news — increasing use of Bt corn has led to historically low populations of European corn borers.

Leave a Reply

Insecticides Stories

InsecticidesHow To Scout For Corn Earworms In Corn
July 28, 2014
In her weekly report, University of Missouri Agronomy Specialist Jill Scheidt discusses what to look for when scouting for corn earworm. Read More
InsecticidesEPA Grants Besiege Insecticide Additional Approvals
June 18, 2014
EPA has granted additional registration approvals for the use of Syngenta's Besiege insecticide on sorghum, cereal grains and peanuts. Read More
InsecticidesPrevathon Insect Control Approved For Cereal Crops
January 13, 2014
DuPont's Prevathon insect control powered by Rynaxypyr has received U.S. EPA registration for use on cereal crops, including wheat, most other small grains and sorghum. Read More
InsecticidesInsecticides 2014: Insect Pressure, Solutions On The Rise
January 2, 2014
Bt resistance, weather concerns and myriad other issues have led to an increase in both traditional pest pressures as well as new pests. Read More

Trending Articles

EquipmentAdvance Your Technology IQ At MAGIE
August 13, 2014
The Midwest AG Industries Exposition (August 20-21) is the place you need to be to see, study and evaluate how new advances in the equipment, operations, crop protection and fertility sectors can help your business prosper. Read More
HerbicidesScouting Key To Next Season’s Soybean Herbicide Program
August 12, 2014
When growing soybeans, growers need to think ahead to stay one step ahead of weeds. That means examining weed threats and evaluating which herbicides work best. Read More
StewardshipMichigan Agriculture Leaders On Toledo Water Ban: We Want To Be Part Of The Conversation
August 8, 2014
Leaders of Michigan agricultural organizations said Thursday that the government should not have a “knee-jerk reaction” based on last weekend’s water ban in Toledo due to fertilizer run-off in Lake Erie. Read More
CropLife 100BRANDT Acquires Lemon Ag Services
August 4, 2014
The acquisition of Lemon Ag fits BRANDT’s aggressive corporate strategy of providing superior agronomic advice and services for customers in central Illinois. Read More
Eric SfiligojThe Resurgence Of Crop Protection
August 4, 2014
Plenty of new offerings over the next few years should see a rebirth for the crop protection products category in terms of market share. Read More
LegislationUSDA Implements Key Farm Bill Crop Insurance Provision
July 30, 2014
The new Supplemental Coverage Option, available through the federal crop insurance program and set to begin with the 2015 crop year, is designed to help protect producers from yield and market volatility. Read More

Latest News

ManagementNCGA DuPont New Leaders Program Enters Sophmore Season
August 20, 2014
The National Corn Growers Association and DuPont are pleased to announce the second year of the NCGA DuPont New Leaders Program. Read More
FungicidesVerdesian Links Up With Mitsui, Hokusan
August 20, 2014
Mitsui Chemicals Agro, Inc., and Hokusan Co., announced the signing of an exclusive licensing agreement allowing Verdesian Life Sciences global access to its patented technology for suppressing mycotoxin contamination in wheat and barley. Read More
SprayersUniversity Of Illinois Introduces New Spray App
August 18, 2014
University of Illinois Extension has released a new smartphone app for making sprayer-related calculations. Pesticide Spray Calculator, or Spray Calc, Read More
Crop InputsSyngenta Names New Manager Of Federal Government Relati…
August 18, 2014
Laura Wood Peterson has joined Syngenta as manager of federal government relations, based in Washington, DC. Read More
ManagementExpert To Discuss Farmland Value, Rent At Farm Science …
August 18, 2014
While cropland values in Ohio increased in the past two years, they have remained flat in 2014, declining in some cases, according to an Ohio State University agricultural economist. Read More
EquipmentDeere Announces Factory Layoffs
August 18, 2014
Deere & Co. has announced it will reduce the size of its manufacturing workforce at some agricultural equipment factories in response to current market demand for its products. Read More
HerbicidesNew DuPont Afforia Herbicide Gives Crops A Clean Start
August 18, 2014
DuPont Afforia is a preplant herbicide for soybeans and other field crops that provides excellent burndown and residual control of many challenging weeds, such as marestail and waterhemp. Read More
Equipment21 Products Showcased At MAGIE 2014
August 18, 2014
The annual Midwest AG Industries Exposition is upon us. Here is CropLife IRON's look at some of the products visitors can expect to see at this week's event. Read More
EquipmentAGCO Seeks Nominations For 2014 Operator Of The Year
August 15, 2014
Ag retailers throughout the U.S. and Canada are encouraged to nominate their best applicators. Read More
EquipmentAdvance Your Technology IQ At MAGIE
August 13, 2014
The Midwest AG Industries Exposition (August 20-21) is the place you need to be to see, study and evaluate how new advances in the equipment, operations, crop protection and fertility sectors can help your business prosper. Read More
ManagementCropLife’s Buyers’ Guide Issue Now Availabl…
August 13, 2014
One of our most read issues of the year — the August Buyers' Guide — is ready to download on the iPad. This popular issue features equipment for "In The Field," "At The Plant" and "In The Office." Read More
WebinarsWebinars On Demand
August 13, 2014
Register for one of our upcoming Webinars or access our archive of past Webinars to view recordings of presentations that may be of interest to you. Read More
HerbicidesBASF: Fall Burndown Benefits Go Beyond Weed Control
August 12, 2014
While unpredictable weather may delay application timing of spring herbicides, more growers are adding a burndown application in the fall Read More
HerbicidesScouting Key To Next Season’s Soybean Herbicide P…
August 12, 2014
When growing soybeans, growers need to think ahead to stay one step ahead of weeds. That means examining weed threats and evaluating which herbicides work best. Read More
StewardshipNitrogen Efficiency Supports Environmental Stewardship
August 12, 2014
As growers prepare for another harvest, it’s important to consider how nitrogen stabilization not only supports healthy plant growth but also fosters environmental stewardship. Read More
Seed/BiotechMycogen Seeds Introduces 19 New Corn Hybrids For 2015
August 12, 2014
Many of the new hybrids feature Mycogen's SmartStax Refuge Advanced technology for maximum protection of the genetic potential and planting convenience. Read More
HerbicidesDow AgroSciences Introduces Enlist Ahead App For Enlist…
August 12, 2014
Designed for use with the Enlist Weed Control System, the app is a precision agriculture tool for maximizing weed control performance, managing weed resistance and making responsible applications of Enlist Duo herbicide with Colex-D Technology. Read More
CropLife 100CHS Announces Senior Leadership Team Changes
August 12, 2014
Current CHS strategic leadership team member Shirley Cunningham will assume a new role as executive vice president and chief operating officer, Ag Business and Enterprise Strategy. Read More