Featured Research

from universities, journals, and other organizations

Cover crop mulches tested for no-till organic onions

Date:
April 21, 2010
Source:
American Society for Horticultural Science
Summary:
Conservation tillage encompasses a range of techniques for establishing crops in the previous crop's residues. Success of the practice in organic systems is highly influenced by crop rotation for weed and disease control and nitrogen availability.

Onion bulbs in remaining cowpea residue mulch are ready for harvest.
Credit: Photo by Emily Vollmer

Conservation tillage encompasses a range of techniques for establishing crops in the previous crop's residues, which are purposely left on the soil surface. The principal benefits of conservation tillage are improved water conservation and the reduction of soil erosion; additional benefits can include reduced fuel consumption, planting and harvesting flexibility, and reduced labor requirements. A new study published in HortScience finds promise in a common legume used as an effective crop cover for organically produced onions.

Related Articles


Conservation tillage promotes soil quality and fertility in accordance with organic principles, but the practice can be challenging. Success of conservation tillage in organic systems is highly influenced by factors such as crop rotation for weed and disease control and nitrogen availability. Surface residues in these systems are usually made up of unharvested crop remains or cover crops that were killed with herbicides (or, in the case of organics, by mechanical methods).

Researchers at North Carolina State University recently released the results of a 2-year experiment designed to assess the efficacy of summer annual grass (foxtail millet) and legume (cowpea) cover crops in different mixture ratios or monocultures. The researchers also analyzed rates of soybean meal as nitrogen amendment on overwintered, no-till, organically managed onion production. Foxtail millet and cowpea were compared with a bare-ground control for weed suppression and nitrogen contribution when followed by organically managed no-till bulb onion production

Cover crop treatments were grown during the summer (July through October) followed by no-till transplanted onions in the fall for overwinter production (November to May). The field experiment was managed according to the U.S. National Organic Program production standards. Cover crop treatments of cowpea and bare ground had the greatest total marketable onion yield both years of the experiments. When supplemental baled millet was applied, however, onion mortality was more than 50%, a result the researchers attributed to the mulch thickness.

The researchers stated that "cowpea shows promise as a summer cover crop used as a residue-mulch for fall planted crops such as overwintered onion. Cowpea produced comparable onion yields to bare ground in both years of the experiment." They noted that, although cowpea had high weed interference, hand-weeding twice was sufficient to maintain onion yields.

Foxtail millet did not function as well as cowpea as a mulch for overwintered onions. According to Emily Vollmer, who led the study; "It appeared that ground coverage and thickness of the grass residue negatively affected onion plant stand and overall yield. Millet in a mixture with cowpea either reduced onion yield or had comparable yield to cowpea as a monocrop." While foxtail millet can perform well as a cover crop when planted in early summer, it was stunted by foliar disease when planted after mid-July, making it a poor choice for a midsummer-seeded cover crop in eastern North Carolina.

Soybean meal showed potential as an effective source of nitrogen even when surface-applied in cool weather months. The study showed that nitrogen would be available for plant uptake in less than 2 weeks after surface-applying soybean meal, which facilitates the use of soybean meal in multiple applications tailored to timing of crop plant demand. The scientists added that split applications of soybean meal could be an important improvement in nitrogen management to better meet increased demand for nitrogen uptake during bulb initiation and growth in the spring.


Story Source:

The above story is based on materials provided by American Society for Horticultural Science. Note: Materials may be edited for content and length.


Cite This Page:

American Society for Horticultural Science. "Cover crop mulches tested for no-till organic onions." ScienceDaily. ScienceDaily, 21 April 2010. <www.sciencedaily.com/releases/2010/04/100421102455.htm>.
American Society for Horticultural Science. (2010, April 21). Cover crop mulches tested for no-till organic onions. ScienceDaily. Retrieved November 27, 2014 from www.sciencedaily.com/releases/2010/04/100421102455.htm
American Society for Horticultural Science. "Cover crop mulches tested for no-till organic onions." ScienceDaily. www.sciencedaily.com/releases/2010/04/100421102455.htm (accessed November 27, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Thursday, November 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Classic Hollywood Memorabilia Goes Under the Hammer

Classic Hollywood Memorabilia Goes Under the Hammer

Reuters - Entertainment Video Online (Nov. 26, 2014) The iconic piano from "Casablanca" and the Cowardly Lion suit from "The Wizard of Oz" fetch millions at auction. Sara Hemrajani reports. Video provided by Reuters
Powered by NewsLook.com
Pet Dogs to Be Used in Anti-Ageing Trial

Pet Dogs to Be Used in Anti-Ageing Trial

Reuters - Innovations Video Online (Nov. 26, 2014) Researchers in the United States are preparing to discover whether a drug commonly used in human organ transplants can extend the lifespan and health quality of pet dogs. Video provided by Reuters
Powered by NewsLook.com
From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Feast Your Eyes: Lamb Chop Sent Into Space from UK

Feast Your Eyes: Lamb Chop Sent Into Space from UK

Reuters - Light News Video Online (Nov. 25, 2014) Take a stab at this -- stunt video shows a lamb chop's journey from an east London restaurant over 30 kilometers into space. Rough Cut (no reporter narration). 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