Palmer amaranth could affect Illinois soybean yield

January 27, 2016
Farmers should learn to identify Palmer amaranth at early growth stages, well before it produces seed. Credit: Aaron Hager.

Although agricultural weed Palmer amaranth (Amaranthus palmeri) primarily impacts southern U.S. states, new research shows it could soon spread further north and damage soybean yields in Illinois.

"We did a common garden study in southern, central, and northern Illinois to ask if different varieties of Palmer amaranth from the south complete their life cycle in all three locations and cause yield loss in . The short answer is yes: there are no current climate limitations to any of the genotypes that we looked at," said University of Illinois weed ecologist Adam Davis. "This is a serious weed."

Illinois farmers are well acquainted with its aggressive cousin, tall waterhemp (Amaranthus tuberculatus), significant infestations of which can cause soybean yield losses of up to 30 percent. Palmer amaranth is an even bigger threat, causing soybean yield losses up to 80 percent in severe cases.

"It's a real economic game-changer," Davis noted. In the study, Davis and his colleagues only allowed Palmer amaranth to compete with soybean for five weeks to avoid seed dispersal and local infestation after the plants had reached maturity. Still, in that time, loss reached 30 percent in some locations.

Unfortunately, Palmer amaranth does not conform to experimental rules in the field.

"It can complete its in a very short period of time. Even if you killed early season populations, if it comes up again in late summer, it can still produce seed by harvest time."

Palmer amaranth already exists in Illinois, but it hasn't become a major problem. "The short take-home message from this research is that Palmer amaranth is mainly seed limited in Illinois," meaning the reason it's not here in greater numbers is simply that not enough seeds have been introduced yet.

To avoid population explosion in Illinois and elsewhere, farmers should learn to identify and remove Palmer amaranth before it goes to seed. Davis also urges farmers to buy certified seed, including cover crop seed and meals, and to be careful about cleaning equipment, especially if it has been purchased out of state. He also suggests diversifying cropping systems to include winter annuals. Additional guidelines for identification and management of Palmer amaranth have been published by the University of Illinois Weed Science Extension service.

"Palmer amaranth (Amaranthus palmeri) damage niche in Illinois soybean is limited," appears in Weed Science. The paper was co-authored by Aaron Hager from the U of I, Brian Schutte from New Mexico State University, and Bryan Young from Purdue University. Funding was provided by the USDA Agricultural Research Service and the Illinois Soybean Association.

Explore further: Palmer amaranth threatens Midwest farm economy, researchers report

More information: Adam S. Davis et al. Palmer Amaranth ( ) Damage Niche in Illinois Soybean Is Seed Limited , Weed Science (2015). DOI: 10.1614/WS-D-14-00177.1

Related Stories

Fungus may offer natural weed control

November 19, 2013

A naturally occurring fungus may prove useful in the fight against Palmer amaranth, an aggressive southern weed that can grow at the rate of two inches a day and outcompete corn, cotton, soybean and other crops for resources, ...

Amaranth seeds may prevent chronic diseases

February 19, 2015

The tiny seed of an amaranth grain may be able to help prevent cardiovascular disease, diabetes, and cancer, according to a review of existing research in Comprehensive Reviews in Food Science and Food Safety published by ...

Recommended for you

Atlas of the RNA universe takes shape

December 7, 2016

As the floor plan of the living world, DNA guides the composition of animals ranging from unicellular organisms to humans. DNA not only helps shepherd every organism from birth through death, it also plays an essential role ...

Gene "bookmarking" regulates the fate of stem cells

December 7, 2016

A protein that stays attached on chromosomes during cell division plays a critical role in determining the type of cell that stem cells can become. The discovery, made by EPFL scientists, has significant implications for ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.