Controlling Volunteer Corn In Soybeans Is Critical

Volunteer corn is much more than a nuisance weed in soybean fields. It could also be a potential threat to the effectiveness of Bt corn hybrids.

A Purdue University entomologist, Dr. Christian Krupke, says that corn hybrids containing insect-resistance genes could become more susceptible to corn rootworms unless growers keep soybean fields free of volunteer corn and continue planting refuge acres.

"What we found was that in areas where triple stack corn was planted in 2006 and soybeans in 2007, we had a great deal of volunteer corn in some of those fields," Krupke says. "Most of that volunteer corn showed up as being Roundup Ready and as having the Bt gene for rootworm."

What worries entomologists is that as producers rotate to soybeans the following year, rootworms feed on volunteer corn and are exposed to Bt toxins produced in the corn plant at less-than-toxic levels, increasing the potential for insect resistance to develop.

More Than a Yield-Robber

Volunteer corn is not an uncommon problem in a typical corn-soybean rotation. And while it’s potential to rob the soybean crop of water, nutrients, sunlight and yield potential has always been known, insect resistance concerns heightens the need for good volunteer corn control.

If you currently plant Roundup Ready corn in your fields, you will need another herbicide besides glyphosate to spray in next year’s Roundup Ready soybean fields to control volunteer corn. "In many cases, if a producer just uses glyphosate in his soybeans, he may need to go in with a second post-emergence treatment containing a graminicide," says Bill Johnson, Purdue University Extension weed scientist. "However, by then the corn has had the opportunity to grow larger and it gives more time for insects to feed, increasing resistance pressure."

Steve Hotovy, Regional Sales Representative with Gowan Company, says this new information increases the need for effective volunteer corn control. "Volunteer corn is a yield robber, especially with current commodity prices," he says. "Producers are looking for effective control."

One graminicide product that has shown consistent control of volunteer corn is Targa herbicide, from Gowan Company. It is a post-emergence grass herbicide that has demonstrated consistent control of both conventional and glyphosate-tolerant volunteer corn in soybeans, in addition to controlling perennial grasses such as Johnsongrass, quackgrass and bermudagrass. Targa can be easily tank-mixed with glyphosate for effective weed control.

"University data does show that Targa’s active ingredient, quizalofop-p-ethyl, provides consistent, effective control compared to other chemistries," says Nick Vandervort, Field Development Manager for Gowan Company. "And Purdue’s findings increase the importance of not only controlling volunteer corn effectively, but doing it as early in the season as possible."
 

Leave a Reply

Latest News
ManagementWashington Visit and Bayer/Monsanto Deal Update
May 26, 2016
Editors Paul Schrimpf and Eric Sfiligoj discusses a recent trip to DC and the latest news on the proposed pairing Read More
Fertilizer closeup in hand
Industry NewsVerdesian: Striking A Balance Between Yield & ROI
May 26, 2016
Finely tuned nutrient management plans are helping farmers throughout the U.S. improve nutrient use efficiency, increase return on investment (ROI) Read More
Crop InputsLand O’Lakes Announces Minnesota Water Quality Pa…
May 25, 2016
Governor Mark Dayton and Land O’Lakes, Inc. President and CEO Chris Policinski today announced a new public-private partnership to protect Read More
Soybean Plant closeup
Industry NewsMonsanto Rejects Bayer Bid; Open To More Talks
May 25, 2016
Monsanto Co, the world’s largest seed company, turned down Bayer AG’s $62 billion acquisition bid as “incomplete and financially inadequate” Read More
Corn close up
Crop InputsArysta LifeScience Establishes Global Headquarters In R…
May 25, 2016
Arysta LifeScience has announced plans to relocate its global headquarters from West Palm Beach, FL, to Cary, NC, over the Read More
fertilizer blending and storage, Top 100
BlendersCHS Dakota Expansion Features AGCO’s GSI InterSys…
May 25, 2016
The continued growth of precision agriculture has increased farmer use of customized fertilizer blends best-suited for their soil conditions. Several Read More
ManagementAgriculture 3.5: A Bumpy Road Ahead
May 24, 2016
You may have read my article a few years ago on Agriculture 3.0, which is a term I coined to Read More
Topcon’s X30 display with CropSpec sensors
EquipmentGPS Autosteer Systems: Product Updates From Precision A…
May 24, 2016
Throughout 2015 GPS Steering solutions continued to evolve from what was once an after-market add on, to today’s cab where Read More
Trimble TMX-2050 In-Cab Display
Eric SfiligojThe Precision Ag Revolution Continues
May 24, 2016
It’s funny how much “the first time” tends to mean to someone as they get older. I sometimes can’t recall Read More
Eric Wintemute, AMVAC
Precision AgAMVAC Ups The Ante With New Precision Ag Technology
May 24, 2016
A potentially industry-changing at-plant soil treatment system from American Vanguard Corp., or AMVAC, is coming soon to large growers in Read More
Dry and Liquid Plant
CropLife 100CropLife 100 Map
May 24, 2016
The new CropLife 100 map shows the locations of each of the headquarters of the 2015 CropLife 100 retailers. The interactive Read More
Southern States Cooperative
Corn Field
Industry NewsTiger-Sul Names Veteran Account Manager To Lead Central…
May 23, 2016
With the continuing growth of the sulphur bentonite and precision crop nutrient industry, global agriculture firm H.J. Baker has announced that Read More
Bayer sign
Industry NewsReuters: Bayer Defies Critics With $62 Billion Monsanto…
May 23, 2016
German drugs and crop chemicals group Bayer has offered to buy U.S. seeds company Monsanto for $62 billion in cash, Read More
Eric SfiligojPity The Monsanto Haters
May 23, 2016
An old saying goes thus: “Be careful what you wish for. You just might get it.” Given current events, there Read More
Industry NewsCompass Minerals Hires Industry Veteran To Lead Plant N…
May 19, 2016
Compass Minerals has hired plant nutrition industry veteran Vatren Jurin to steer the company’s portfolio expansion into specialty liquid micronutrient Read More
ASMARK Retailers LIVE! Tour 2016 Group shot The Andersons
CropLife 100The Andersons Rejects Unsolicited Proposal From HC2
May 19, 2016
The Andersons, Inc. has announced that its Board of Directors has rejected two non-binding, highly conditional, unsolicited proposals from HC2 Read More
glyphosate
Crop InputsWHO: Glyphosate ‘Unlikely’ To Cause Cancer
May 16, 2016
Via Reuters.com reporter Kate Kelland: The weed-killing pesticide glyphosate, made by Monsanto and widely used in agriculture and by gardeners, Read More