Nematodes are the most abundant animals on the planet. And while soybean farmers are most familiar with soybean cyst nematode (SCN), they aren't the only species that threaten production.

Sorting the bad nematodes from the good (yes ... there are some good ones) is important to help farmers stay ahead of emerging threats. The SCN Coalition has expanded its educational outreach to create the Soybean Nematode Management Guides, providing practical tools and science-based strategies to identify and manage four yield-robbing, parasitic nematode species.

Think of these guides like "a wanted poster" for each of the four pests. Nematode management isn't one-size-fits-all, as several species can infest soybean fields -- each with distinct life cycles, symptoms and impacts on yield. These guides, funded by the United Soybean Board (USB) and developed by Extension plant pathologists and nematologists, will help you hunt down:

-- Soybean cyst nematode (SCN): Known as the No. 1 yield-grabbing pathogen of the soybean crop in North America, SCN causes up to 30% yield loss without demonstrating noticeable aboveground symptoms, leading to annual losses exceeding $1.5 billion.

-- Root-knot nematode (RKN): Another widespread threat, RKN species -- including Southern RKN -- can cause 25% yield loss in individual fields and is found in most soybean production regions in the United States.

-- Root lesion nematode (RLN): A collection of more than 100 species, RLN's impact on yield extends beyond soybeans. With a broad host range, RLN can also reduce yield in rotational crops, including corn, and lead to recurring economic losses.

-- Reniform nematode: A significant pathogen in the Southern U.S. for cotton and soybean farmers, reniform nematode can cause more than a 10% yield loss in individual fields.

New quantitative research conducted by The SCN Coalition of 271 farmers in Southern soybean areas shows roughly 80% of farmers are aware of SCN and RKN, while other nematode species that affect soybean yield like RLN and reniform are less understood. When high numbers of these nematodes coincide with drought or other stressful environmental conditions, soybean yield reductions can become even more severe.

Additional farmer survey results found:

-- 44% said they scout or conduct nematode soil sampling.

-- 57% rely on aboveground symptoms to diagnose nematodes.

-- 72% rely on crop rotation to manage nematodes.

-- 65% support checkoff-funded research to develop new nematode management tools.

"Soybean farmers have been exposed to active SCN management messages, but nematode pressure doesn't stop there," observed Dylan Mangel, plant pathologist at the University of Nebraska-Lincoln, in a news release. "Addressing these lesser-known and still-damaging nematode species helps farmers close information gaps and take a more comprehensive approach to protect yield from nematodes. It's also an opportunity for the Coalition to expand its reach and impact."

MANAGEMENT TOOLS TO USE

It's impossible to eliminate nematode pressure from an infested field, but the Soybean Nematode Management Guides are designed to arm soybean farmers with multiple active management strategies shown to effectively reduce plant-parasitic nematodes' impact on yield.

"An integrated approach using multiple active management strategies can keep nematode populations low and protect soybean yield," said Horacio Lopez-Nicora, soybean pathologist and nematologist at Ohio State University. "By adopting a proactive, informed management plan and using the practices found in these management guides, farmers can reduce plant-parasitic nematode pressure and help protect soybean yield and overall crop productivity."

"These management guides are designed with the farmers' needs in mind," said Laurie Isley, United Soybean Board director and Michigan farmer. She noted that the guides are designed to be easily used by farmers. In addition to step-by-step soil-testing instructions and symptoms identification, the guides include management options like planting resistant soybean varieties, crop rotation, use of nematode-protectant seed treatments and other cultural practices that promote root health.

"Along with working with your local agronomic expert, farmers can equip themselves with practices to manage nematode pressure to meet their soybean yield goals," she added.

Available online and for digital download, the four Soybean Nematode Management Guides can be found at https://www.thescncoalition.com/….

For additional DTN reports on SCN go to:

-- "Take Time to Outsmart Nematodes," https://www.dtnpf.com/…

-- "Soybean Cyst Nematodes Like Dry Conditions," https://www.dtnpf.com/…

Pamela Smith can be reached at pamela.smith@dtn.com

Follow her on social platform X @PamSmithDTN

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