Soil fungus could suppress soybean cyst nematodemore—cause of over $1 billion in yield losses every year

px soybean cyst nematode and egg sem
Microscopic view of soybean cyst nematode and its egg. Credit: USDA

The soybean cyst nematode sucks the nutrients out of soybean roots, causing more than $1 billion in soybean yield losses in the U.S. each year. A new study finds that one type of fungi can cut the nematodes’ reproductive success by more than half.

The researchers report their findings in the journal Plant Disease.

“Soybean cyst nematodes survive in the soil as eggs in cysts,” said Glen Hartman, a researcher for the U.S. Department of Agriculture’s Agricultural Research Service in the department of crop sciences at the University of Illinois at Urbana-Champaign. Hartman led the new research with graduate student Michelle Pawlowski. “The eggs hatch at the start of the growing season, and the juveniles penetrate root tissue and migrate into the plant’s vascular system. The females find a feeding site and stay there for the rest of their lives. They take nutrients away from the soybean plant, which reduces plant productivity.”

Previous studies have found that fungi in the soil that form mutually beneficial relationships with soybeans and other plants can influence the success of plant parasitic nematodes, including SCN. But the effectiveness of using these “arbuscular mycorrhizal fungi” to thwart plant parasitic fungi varies from study to study, making growers reluctant to embrace this as a method of control, Hartman said.

“In this study, we focused on five different species of arbuscular mycorrhizal fungi to see if they differed in their ability to protect soybeans against SCN,” Pawlowski said.

Related article:  A tale of three GMOs: Intellectual contradiction?

The researchers inoculated young soybean plants with fungi and SCN in greenhouse experiments. By the end of the experiment, all five fungal species had reduced the number of SCN cysts in the roots. The lowest number of cysts occurred on plants inoculated with the fungus Funneliformis mosseae. These averaged 10 cysts per plant. Soybean plants that were not inoculated with fungi accumulated 75 or more cysts per plant.

“Each cyst may contain hundreds of nematode eggs,” Hartman said.

Further experiments with F. mosseae revealed that exposure to the fungus reduced the number of juvenile nematodes on the plants by more than half.

“We found that as early as seven days after inoculation, roots that were inoculated with F. mosseae were colonized with significantly fewer nematode juveniles,” Pawlowski said.

“To see if this interaction and suppression might occur even earlier, we incubated SCN eggs in sterile water alone, with fungal spores or with exudates of the fungal spores. These exudates are microbes and molecules secreted by the spores,” she said.

This experiment revealed that the fungal spores and their exudates undermine nematode egg hatching, she said.

“If we can find out what function or compound from the fungi is suppressing egg hatching, that could potentially be a useful nematicide,” Pawlowski said.

Read the original post

Outbreak
Outbreak Daily Digest
Biotech Facts & Fallacies
Talking Biotech
Genetics Unzipped
Video: Test everyone – Slovakia goes its own way to control COVID

Video: Test everyone – Slovakia goes its own way to control COVID

As Europe sees record coronavirus cases and deaths, Slovakia is testing its entire adult population. WSJ's Drew Hinshaw explains how ...
mag insects image superjumbo v

Disaster interrupted: Which farming system better preserves insect populations: Organic or conventional?

A three-year run of fragmentary Armageddon-like studies had primed the journalism pumps and settled the media framing about the future ...
dead bee desolate city

Are we facing an ‘Insect Apocalypse’ caused by ‘intensive, industrial’ farming and agricultural chemicals? The media say yes; Science says ‘no’

The media call it the “Insect Apocalypse”. In the past three years, the phrase has become an accepted truth of ...
globalmethanebudget globalcarbonproject cropped x

Infographic: Cows cause climate change? Agriculture scientist says ‘belching bovines’ get too much blame

A recent interview by Caroline Stocks, a UK journalist who writes about food, agriculture and the environment, of air quality ...
organic hillside sweet corn x

Organic v conventional using GMOs: Which is the more sustainable farming?

Many consumers spend more for organic food to avoid genetically modified products in part because they believe that “industrial agriculture” ...
benjamin franklin x

Are most GMO safety studies funded by industry?

The assertion that biotech companies do the research and the government just signs off on it is false ...
favicon

Environmental Working Group: EWG challenges safety of GMOs, food pesticide residues

Known by some as the "Environmental Worrying Group," EWG lobbies for tighter GMO legislation and famously puts out annual "dirty dozen" list of fruits and ...
m hansen

Michael Hansen: Architect of Consumers Union ongoing anti-GMO campaign

Michael K. Hansen (born 1956) is thought by critics to be the prime mover behind the ongoing campaign against agricultural biotechnology at Consumer Reports. He is an ...
News on human & agricultural genetics and biotechnology delivered to your inbox.
Optional. Mail on special occasions.
Send this to a friend