Ohio State University examines the yield value of a high-input soybean system and determines what soil factors may be limiting yields.

As soybean prices continue to compete with corn — a price difference just shy of $10 per bushel, according to the Web sites Quotecorn.com and Quotesoybeans.com — attention to the crop continues to grow.

Some growers may wonder if a high-input system typically used for corn should also be applied to soybeans. In a webinar hosted earlier this year, Ohio State University crop and soil scientist Laura Lindsey shared the preliminary results of a study that explored that very question.

Evaluating Inputs

First, researchers asked themselves: What can we add to soybeans to increase yields? To answer that question, they conducted trials at nine locations in Ohio to compare five inputs: inoculants, gypsum, fungicide, insecticide and manganese fertilizer.

Researchers looked at the yield difference between soybeans that had all five inputs (Figure 1) and soybeans that had all but one of the inputs, to see if there was a yield reduction when a specific input was missing.

They also took the opposite approach, by comparing soybeans that had no inputs added (traditional) and observing whether there was a yield increase when a single input was added. The input applications were all made at the R3 stage.

Figure 1. The chart shows how Ohio State University conducted its input omissions trials, by taking one input away from the high-input soybeans, as well as adding one input to the traditional (no