Featured Research

from universities, journals, and other organizations

Prior herbicide use -- not irrigation -- is critical to herbicide efficacy

Date:
May 5, 2010
Source:
USDA/Agricultural Research Service
Summary:
Crop and herbicide use history are more critical to herbicide efficacy and environmental safety than the timing and amount of irrigation water used, according to agricultural scientists.

ARS plant physiologist Dale Shaner has found that, while the herbicide atrazine breaks down more quickly in fields that have been previously treated with the herbicide, the amount of irrigation does not affect the degradation rate at all.
Credit: Photo by Peggy Greb

Crop and herbicide use history are more critical to herbicide efficacy and environmental safety than the timing and amount of irrigation water used, according to Agricultural Research Service (ARS) scientists.

Related Articles


ARS plant physiologists Dale Shaner and Lori Wiles made this discovery from ongoing experiments on two irrigated fields at Colorado State University (CSU) at Fort Collins, Colo. Shaner and Wiles work in the ARS Water Management Research Unit at Fort Collins.

In collaboration with CSU colleague Neil Hansen, Shaner and Wiles compared the behavior of the herbicide atrazine in conventionally tilled corn grown continuously year after year versus corn grown in three different crop rotations. They tested various levels of tillage and irrigation, including no irrigation.

The amount of irrigation used -- including a total absence of irrigation -- had no impact on the rate of degradation of atrazine by soil microbes in the top foot of soil. The only factors that made a difference were prior herbicide use and the choice of crop sequences, with prior herbicide use the most important factor by far.

Earlier studies, including one by Shaner, have shown that previous applications of atrazine can predispose soil to more quickly degrade later applications of the herbicide. But until now, it was not clear if other factors such as cropping history and quantity of irrigation played a role.

There are two consequences of the more rapid dissipation of atrazine in the plots with a history of use. The first consequence is a loss in weed control. In the plots with the most rapid dissipation, weeds began to re-infest the plots within four weeks after treatment, while the plots with the slowest rate of dissipation remained weed-free through the growing season.

The second consequence is that atrazine leached more deeply in the soil in the plots where it did not dissipate rapidly, but the herbicide did not move below the top three inches of the soil in the plots where it was degraded rapidly.

This research was published in the Journal of Environmental Quality.


Story Source:

The above story is based on materials provided by USDA/Agricultural Research Service. The original article was written by Don Comis. Note: Materials may be edited for content and length.


Journal Reference:

  1. Dale L. Shaner, Lori Wiles, and Neil Hansen. Behavior of Atrazine in Limited Irrigation Cropping Systems in Colorado: Prior Use Is Important. Journal of Environmental Quality, 2009; 38 (5): 1861 DOI: 10.2134/jeq2008.0463

Cite This Page:

USDA/Agricultural Research Service. "Prior herbicide use -- not irrigation -- is critical to herbicide efficacy." ScienceDaily. ScienceDaily, 5 May 2010. <www.sciencedaily.com/releases/2010/03/100317101353.htm>.
USDA/Agricultural Research Service. (2010, May 5). Prior herbicide use -- not irrigation -- is critical to herbicide efficacy. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2010/03/100317101353.htm
USDA/Agricultural Research Service. "Prior herbicide use -- not irrigation -- is critical to herbicide efficacy." ScienceDaily. www.sciencedaily.com/releases/2010/03/100317101353.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Monarch Butterflies Descend Upon Mexican Forest During Annual Migration

Monarch Butterflies Descend Upon Mexican Forest During Annual Migration

Reuters - Light News Video Online (Dec. 19, 2014) Millions of monarch butterflies begin to descend onto Mexico as part of their annual migration south. Rough Cut (no reporter narration) Video provided by Reuters
Powered by NewsLook.com
Birds Might Be Better Meteorologists Than Us

Birds Might Be Better Meteorologists Than Us

Newsy (Dec. 19, 2014) A new study suggests a certain type of bird was able to sense a tornado outbreak that moved through the U.S. a day before it hit. Video provided by Newsy
Powered by NewsLook.com
Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins