Navigation Links
Herbicide diversity needed to keep Roundup effective

WEST LAFAYETTE, Ind. - Using a diverse herbicide application strategy may increase production costs, but a five-year Purdue University study shows the practice will drastically reduce weeds and seeds that are resistant to a popular herbicide.

Excess usage of glyphosate-resistant crops has led to weeds, such as marestail, that also are resistant to glyphosate, the herbicide used in Roundup. Bill Johnson, a Purdue associate professor of weed science, said changing management practices can almost eliminate resistant marestail and its viable seeds in the soil.

"Another herbicide application is expensive, and it means more trips across the field," Johnson said. "But we can reduce the population and density of resistant weeds, which increases the crop yield potential."

The results of Johnson's five-year study were published in the journal Weed Science.

Marestail, also known as horseweed, was the first weed to develop resistance to glyphosate. Other weeds also are adapting, Johnson said, reducing the effectiveness of products such as Roundup, the most widely used herbicide on the market.

It is Roundup's popularity that is contributing to its diminished effect. Johnson said farmers have come to rely on Roundup Ready crops that resist glyphosate as an easy way to control weeds. But overuse of any herbicide allows weeds to adapt and develop resistance.

Johnson's study found that farmers should diversify the herbicides they use. Using a variety of herbicides in addition to Roundup before planting and alternating between Roundup and other herbicides in corn can significantly reduce marestail.

Fields that had three resistant weeds for every susceptible weed while using only Roundup and Roundup Ready crops saw weed populations drop to one resistant weed for every six susceptible weeds while rotating herbicides as Johnson suggests. That rotation also may lead to a 95 percent decrease in the number of viable marestail seeds in the soil.

Continuing with only Roundup and Roundup Ready crops can intensify the problem, Johnson said.

"Glyphosate-resistant marestail develops very quickly in a field. Populations reach staggering levels of infestation in about two years after it is first detected," Johnson said. "For us, marestail being the first weed that developed resistance showed that a weed-management system that is solely reliant on glyphosate is starting to break down. However, a system that incorporates other herbicides with glyphosate can be sustainable for quite some time."

The Indiana Soybean Alliance, BASF, Dow AgroSystems, Monsanto and Syngenta funded Johnson's study. His next step is looking at management strategies that reduce the prevalence of other weeds that have built up resistance to glyphosate.


Contact: Brian Wallheimer
Purdue University

Related biology news :

1. Researchers discover natural herbicide released by grass
2. Herbicide-tolerant crops can improve water quality
3. How are herbicides discovered?
4. Herbicide-resistant grape could revitalize Midwest wine industry
5. Low level herbicide use can damage potato reproduction
6. Coral reef fish harbor an unexpectedly high biodiversity of parasites
7. Spatial patterns in tropical forests can help to understand their high biodiversity
8. Hydrothermal vents: Hot spots of microbial diversity
9. Upper Midwest forests are losing diversity, complexity, ISU study finds
10. NAS Biodiversity and Extinction Meeting Dec. 7-8
11. How global is the Global Biodiversity Information Facility?
Post Your Comments:
(Date:11/16/2015)... SAN JOSE, Calif. , Nov 16, 2015 ... leading developer of human interface solutions, today announced ... new Synaptics TouchView ™ touch controller and ... the architectural revolution of smartphones. These new TDDI ... and include TD4100 (HD resolution), TD4302 (WQHD resolution), ...
(Date:11/12/2015)... Mass. , Nov. 12, 2015  Arxspan ... Institute of MIT and Harvard for use of ... discovery information management tools. The partnership will support ... both biological and chemical research information internally and ... will be used for managing the Institute,s electronic ...
(Date:11/11/2015)... 2015   MedNet Solutions , an innovative SaaS-based eClinical ... is pleased to announce that it will be a Sponsor ... event, to be held November 17-19 in Hamburg ... demonstrations of iMedNet , MedNet,s easy-to-use, proven ... has been able to deliver time and cost savings ...
Breaking Biology News(10 mins):
(Date:11/30/2015)... Partnership includes an MPP ... for the u niversity , s Solid ... s cale - up through ... Africa , where licensees based anywhere in the world will have the ... --> Africa , where licensees based anywhere in the world will ...
(Date:11/30/2015)... 30, 2015 Spherix Incorporated (Nasdaq: ... the fostering and monetization of intellectual property, today ... initiatives designed to create shareholder value. ... Spherix. "Based on published reports, the total addressable ... billion and Spherix will seek to secure fair ...
(Date:11/30/2015)... 2015 TapImmune, Inc. (TPIV), ... innovative peptide and gene-based immunotherapeutics and vaccines for the ... will be presenting at the 8 th Annual ... 2.30 PM PT. Dr. John N. Bonfiglio ... giving the presentation and will join TapImmune management in ...
(Date:11/30/2015)... RATON, Florida and MAGDEBURG, Germany ... Congress of NeuroRehabilitation (ECNR) in Vienna, Austria ... 3rd European Congress of NeuroRehabilitation (ECNR) in ... 2015. --> NovaVision, a wholly owned subsidiary of ... the European version of its Internet-delivered NovaVision Therapy Suite at ...
Breaking Biology Technology: