Managing for Profit

Myriad of problems in soybean fields

Depending on where soybeans are being grown, the factors that have led to this point in the growing season vary considerably.

But in general, the crop is challenged by weeds, insects and diseases.

One of them has reared its ugly head in southern Minnesota, where the plants tended to get pretty tall according to DuPont Pioneer agronomist Clyde Tiffany.

“We tended to have very good vegetative growth.  The downside of that is you get a very wet canopy, and a wet canopy allows the infection to occur.  the white mold spores enter through the defecating flower.  So as the (soybeans) flower, whether it’s low in the canopy or up high; if there’s free water there the spore can enter.  What you will start to see is dead plants, where they will just start turning brown on you.”

Tiffany says farmers need to go into the field to pull up plants.

“Look on the stems.  Usually you’re going to see white mold on the outside, or you can cut the stems open.”

He tells Brownfield it should be apparent and infection can occur stem to stem.

There isn’t much a grower can do at this point, but in the future Tiffany says there are some management options.

“Controlling your canopy size and your row width.  So the wider your row, the more air you have moving through that.  The downside of that is we’re trying to control weeds too, so you want the canopy to close.  That’s the dilemma.  You want the canopy closed, but once you have white mold those fields are more likely to have problems.  Especially if they’ve been highly manured or there’s been a high amount of nitrogen.”

Another disease that’s starting to appear is sudden death syndrome, or SDS.

Brad Skifter owns SKG Ag Services based in southeast Minnesota and says discoloration is a tell-tale sign.

“The beans showing green, but the rest of it turning yellow.  That could also be from other diseases or fertilizer deficiencies.  But, for the most part what we’re seeing out there with that symptomology is the SDS.”

He tells Brownfield some soybean varieties are more susceptible to SDS than others, and if it’s present in the soil, seed selection will be critical for next year.