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

Crop InputsPlatform Specialty Products To Acquire Arysta LifeScience
October 20, 2014
Once the acquisition is complete, Platform Specialty Products will combine Arysta LifeScience with previously acquired companies Agriphar and Chemtura Crop Solutions. Read More
Seed/BiotechMonsanto Offers New Support For Ferguson, Area Communities
October 8, 2014
Monsanto Co. has committed $1 million in new support for several collaborative efforts in Ferguson, MO, and surrounding communities in North St. Louis County. Read More
Seed/BiotechUnapproved Genetically Modified Wheat Found In Montana
October 3, 2014
USDA reports that one year after discovery of Monsanto's unapproved wheat in a single Oregon field disrupted U.S. wheat export sales, the GMO wheat has again been found in Montana. Read More
Equipment2014 Product Of The Year Voting
September 19, 2014
The deadline to vote for the 2014 CropLife IRON Product of the Year is October 31. Please cast your vote today to help us determine the winner. Read More
FertilizerFall Fertility 2014: Forecasting Fertilizer Use
September 7, 2014
Great crops this year have tapped the soil, and fall work is definitely called for, but how challenging will that get? Read More
CropLife 100CHS To Build $3 Billion Fertilizer Plant In North Dakota
September 5, 2014
The fertilizer plant in Spiritwood will be the single largest investment in CHS history, as well as the single largest private investment project ever undertaken in North Dakota. Read More

Latest News

InsecticidesValent U.S.A., MGK Form Marketing Agreement
October 24, 2014
Valent has formed an agreement with Minneapolis-based MGK to manage the marketing and sales of MGK’s crop protection line of insect control products within the U.S. beginning April 1, 2015. Read More
StewardshipFlorida’s 4R Advocate Keeps Improving
October 24, 2014
Florida farmer Alan Jones uses the 4R principles of nutrient stewardship as the core of his fertility program, which allows him to maximize production and keep costs in check. Read More
Seed/BiotechMonsanto Named One Of The World’s Best Multinational …
October 23, 2014
Monsanto ranked No. 8 in the world’s largest annual study of workplace excellence that identifies the top 25 best multinational companies in terms of workplace culture. Read More
Crop InputsArysta Hires Former Agri-Chem, CPS Employee For Delta S…
October 23, 2014
New Territory Sales Manager Mark Peel’s primary role will focus on working with growers regarding fungicides in Louisiana, Mississippi, Arkansas and Tennessee. Read More
CropLife 100GROWMARK Announces Appointments In Plant Food Division
October 22, 2014
GROWMARK, Inc. has announced the three key staff changes in its Plant Food Division. Read More
CropLife 100GROWMARK Appoints New VP Of Finance And Risk Management
October 22, 2014
Wade Mittelstadt has been named GROWMARK Vice President, Financial and Risk Mangement, effective December 1, 2014. Read More
FungicidesEPA Approves BASF In-Furrow Corn Fungicide
October 22, 2014
Field trials show Xanthion In-furrow fungicide provides more rapid emergence, extended residual control and improved seedling health than untreated crops. Read More
EquipmentAgraScout App Available At No Cost To Universities
October 21, 2014
AgraScout, a fast and easy to use mobile crop scouting app, is now available at no cost to University students, Read More
LegislationNew Farm Bill Program To Provide Relief To Farmers Affe…
October 21, 2014
The USDA has implemented a new Farm Bill initiative that will provide relief to farmers affected by severe weather, including drought. Read More
ManagementGreenfield Scholars Program Aims To Sustain Agronomy Wo…
October 21, 2014
The program encourages talented students to study agronomy, crop and soil sciences while cultivating networks to develop the necessary workforce to sustain the profession. Read More
Paul SchrimpfPrecision Ag: Taking It To The Hill
October 21, 2014
A new coalition took the good news message of precision agriculture to Washington, DC, last month. Read More
ManagementUSDA Awards $18 Million In Small Business Research Gran…
October 21, 2014
The grants will provide high quality, advanced research and development that will lead to technological innovations and solutions for American agriculture. Read More
FertilizerCF Industries Terminates Merger Discussions With Yara I…
October 21, 2014
CF Industries Holdings and Yara International have terminated their discussions regarding a potential merger of equals transaction. Read More
Seed/BiotechSyngenta Ranked A Top 10 Biotech Employer For Third tim…
October 20, 2014
Syngenta ranked in the top 10 among the world’s top biotech employers, according to an annual survey conducted by Science magazine. Read More
CropLife 100Wheat Growers Break Ground For New Facility At Kennebec
October 20, 2014
Wheat Growers has broke ground for a state-of-the-art shuttle loader grain handling, fertilizer and agronomy facility in Kennebec, SD. Read More
FertilizerVerdesian Life Sciences Signs Agreement With Los Alamos…
October 20, 2014
Verdesian Life Sciences has signed a licensing agreement with Los Alamos National Laboratory to develop and market LANL’s latest nitrogen enhancement technology for plants. Read More
MicronutrientsStoller Group Announces Groundbreaking At New Office Bu…
October 20, 2014
Jerry Stoller, founder and president of Stoller Group, announced the groundbreaking at the site of the company’s future headquarters in Read More
Crop InputsBioSafe Systems Opens New Production Facility In Nevada
October 20, 2014
BioSafe Systems has completed construction of a state-of-art production facility in Sparks, NV, for its line of activated peroxygen products. Read More