Featured Research

from universities, journals, and other organizations

Helping Beneficial Fungi Work

Date:
May 10, 2004
Source:
USDA / Agricultural Research Service
Summary:
Certain fertilizers can actually inhibit beneficial, naturally occurring fungi that help plants use water and nutrients while suppressing diseases, according to an Agricultural Research Service scientist studying these beneficial root-dwelling fungi.

To determine the effects of compost on mycorrhizae in greenhouse production of nursery crops, plant pathologist Robert Linderman and technician Anne Davis grow plants (marigolds shown here) in a potting mix with various levels of compost. Some plants are inoculated with mycorrhizal fungi and others are not. Compost was added to the larger plant that Linderman is holding (left) while none was added to the smaller plant.
Credit: Photo by Peggy Greb / Courtesy USDA / Agricultural Research Service

Mycorrhizal fungi—naturally occurring, beneficial soil organisms—have been helping farmers for thousands of years by improving water and nutrient use efficiency and suppressing diseases in the plants they colonize. Applying certain chemicals to the soil during the last half century-while increasing crop yields and fighting diseases-has likely inhibited these important fungi.

Agricultural Research Service plant pathologist Robert G. Linderman is one of only a few scientists studying how mycorrhizae affect the nutrition and health of nursery crops. Other ARS scientists look at the fungi in food crops.

At the Horticultural Crops Research Laboratory in Corvallis, Oregon, Linderman is investigating various factors that affect mycorrhizal relationships. He measures the level of mycorrhizal colonization of roots and compares it to control groups to see how effective various treatments are.

Linderman first looked at dozens of fertilizers on various nursery crops—particularly marigolds, because they are very responsive to mycorrhizae—to see whether they help or inhibit fungal growth. He found that organic fertilizers are generally compatible with mycorrhizae, whereas phosphorus-rich inorganic fertilizers inhibit the fungi.

"It's good that organic fertilizers don't inhibit mycorrhizae, but the plants do not grow as large or as fast as the ones treated with inorganic fertilizers," Linderman explains. Manufacturers of organic fertilizers are now advising users to apply more than they were previously. This allows plants to grow normally without interfering with mycorrhizae.

Linderman is looking at other things growers add to their potting mixes. Peat moss has traditionally been a popular component in potting mixes. Linderman observed that some peat types suppress mycorrhizal associations, while others do not.

Instead of peat, some growers are starting to use coir (fibers from coconut) as a potting mix component. Coir has a more uniform texture than peat, and it has a better water-absorbing and nutrient-holding capacity. Linderman's studies show that coir—like organic fertilizers—does not inhibit mycorrhizae, although it may reduce growth of some plants.

Linderman is researching composts that might be added to potting mixes. Composts differ in the types of materials they contain. Nurseries in different parts of the country also use different amounts of compost in their media. Even the way compost is made and stored makes a big difference. "Overall, presumably because of the high levels of phosphorus, fresh composts appear to suppress mycorrhizae," Linderman says. But some very mature composts are not inhibitory.

Linderman admits he has not settled on the one perfect ingredient to add to potting mixes that will establish mycorrhizae in nursery crops and produce healthy plants. "Growers just need to think ahead of time what will happen when a particular product is used, since they wouldn't want to add an ingredient that would suppress the beneficial fungi."—By David Elstein, Agricultural Research Service Information Staff.

This research is part of Methyl Bromide Alternatives (#308) and Plant Diseases (#303), two ARS National Programs described on the World Wide Web at www.nps.ars.usda.gov.


Story Source:

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


Cite This Page:

USDA / Agricultural Research Service. "Helping Beneficial Fungi Work." ScienceDaily. ScienceDaily, 10 May 2004. <www.sciencedaily.com/releases/2004/05/040510010924.htm>.
USDA / Agricultural Research Service. (2004, May 10). Helping Beneficial Fungi Work. ScienceDaily. Retrieved September 20, 2014 from www.sciencedaily.com/releases/2004/05/040510010924.htm
USDA / Agricultural Research Service. "Helping Beneficial Fungi Work." ScienceDaily. www.sciencedaily.com/releases/2004/05/040510010924.htm (accessed September 20, 2014).

Share This



More Plants & Animals News

Saturday, September 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Chocolate Museum Opens in Brussels

Chocolate Museum Opens in Brussels

AFP (Sep. 19, 2014) Considered a "national heritage" in Belgium, chocolate now has a new museum in Brussels. In a former chocolate factory, visitors to the permanent exhibition spaces, workshops and tastings can discover derivatives of the cocoa bean. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com
Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
Powered by NewsLook.com
Raw: Elephant Undergoes Surgery in Tbilisi Zoo

Raw: Elephant Undergoes Surgery in Tbilisi Zoo

AP (Sep. 18, 2014) Grand the elephant has successfully undergone surgery to remove a portion of infected tusk at Tbilisi Zoo in Georgia. British veterinary surgeons used an electric drill to extract the infected piece. (Sept. 18) Video provided by AP
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:
from the past week

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