Soybean Cyst Nematode Is The Crop's Biggest Yield-Robbing Pest

101318 Farm Journal Report
Iowa State University expert says the SCN Coalition is designed to remind farmers that they are losing yield to soybean cyst nematode - probably more so than ever before - because the resistant varieties are not working as well. ( Farm Journal )

A deluge of rain has pummeled the corn belt this year. Iowa farmers are seeing everything from heavy rains to snow in some areas.

“We've had a lot of rain, said Mike Schropp, farmer in Western Iowa. “We did get out there and do some planting, but it just keeps raining.”

While farmers like Schropp wait to plant, they’re forced to watch a bountiful crop wash away.

“Even on upland ground the water is so high that the water can't get away,” said Schropp. “Creeks are backing up; nothing is running into the river. It's bad.”

It’s a disheartening sight as area farmers are hungry to harvest what has the potential to be a record.

“It's pretty good out there yet, in places really good, but it's going to be a nightmare to get it all,” he said.

Just down the road, Mike Maguire is also living the harvest nightmare.

He said there has been instances this fall when as much as 10 inches of rain has fallen over two days; rain that he didn’t see this summer. says 10 inches of rain fell over two days.. rain he didn't see this summer. It’s been a rollercoaster year of weather that’s picking up steam when farmers are not only trying to close the books on 2018, but plan for the growing season ahead.

It's during the rhythm of harvest when Iowa State University nematologist Greg Tylka enters the picture. 

“I live and breathe soybean cyst nematode,” said Tylka.

He said it’s a nematode issue creeping into many fields unbeknownst to many farmers.

“It's very similar to weeds becoming resistant to herbicides, but I really started to notice it the last 15 years ago,” said Tylka. “In the 2000s is when I started to see resistance soybean varieties not working as well.”

Tylka said as resistance started popping up, he knew it was time to revisit an idea the industry had nearly 30 years ago.

“In the 90s we did the first SCN (soybean cyst nematode) coalition to make farmers aware of this pest, and it was that simple,” said Tylka. “Once a farmer realized he or she had a problem with soybean cyst nematode there were lots of resistant soybean varieties to use in rotation with non-host crops, and the problem was taken care of.”

Today, it's the Soybean Cyst Nematode Coalition (SCN Coalition) is made up of University experts and companies working to address the pest.

“The goal these days with the new SCN coalition is to remind farmers that they are losing yield to soybean cyst nematode - probably more so than ever before - because the resistant varieties are not working as well,” he said.

Sam Markell is a North Dakota State professor and extension plant pathologist. He said by the time some farmers realize they have an issue, it can be a major problem in their fields.

“Even a larger percentage don't know if they have it or not. and that's a really dangerous situation,” said Markell. “It's one of those things that you can manage if you find it but you've got to look for it first.”

Markell says that's why he wants farmers to test for it before it's too late.

“At harvest, we want them to go soil sample send in a sample to see if you've got it and to see how severe it is,” said Markell. “If you have it then you start to use the management tools that we have: resistance, rotation, maybe a seed treatment in some in some cases.”

He said it’s a yield robbing pest and the yield loss numbers are staggering.

“In North Dakota where we see it introduced, we see it show up in our variety trials where we have susceptible and resistant varieties, it's usually taken about 40 percent yield loss,” he said.

Both Tylka and Markell are on a mission; education that will hopefully save bushels in the end,

while trying to save the yields of tomorrow, today.