Here’s a mission: Grow more soybean bushels per acre at the least cost. This is all part of a research project that researchers including Seth Naeve, University of Minnesota Extension agronomist are conducting in soybean-growing states ranging from the Delta to northern states like Minnesota and Michigan. This work is funded by a grant from the United Soybean Board. Areas of research include:

• Seeding rates
• Ways to maximize light interception
• Maturity groupings
• High inputs
• Direct applications of fertilizer to soybean crops
• Soybean seed quality (protein and oil)

"Our goal is to develop a uniform set of recommendations for growers across the U.S.,” says Naeve. “We're getting answers, but we don't have all of them yet."  

The 'kitchen sink'

Higher grain prices help to justify inputs that wouldn’t be justified at lower prices. That’s prompted a “kitchen sink” approach in one of the soybean studies in Minnesota, Michigan, Iowa, Kentucky, Arkansas and Louisiana.

"We're throwing everything we have at these soybeans to see what happens, what has the best chance of succeeding and providing a return to growers,” says Seth Naeve, University of Minnesota Extension agronomist.

Practices being tested include:

• Several fertility applications including phosphorus, potassium, sulfur, boron, manganese and zinc.
• Seeds that are inoculated before planting to improve nodulation and nitrogen fixation.
• Seeds that receive a fungicide treatment before planting.
• Foliar fertilizer applications applied later in the season, along with one or two foliar fungicide applications.

"They all have increased yields in some of our trials," says Naeve. "In total, the 'kitchen sink' has added about five bushels per acre, from an average of 58 up to 63. Fertilizer has shown the least response, yields have been just slightly lower when we didn't fertilize. Most of the positive impact was in research in Michigan." The seed fungicide treatments impacted yield very little.

"Our biggest yield response to date has been the foliar fungicides later in the season," Naeve says. "What we know at this point is that we can increase yields by pouring on the products and inputs, but we can't point to one single practice that drives this."