Should 50-year-old soybean nutrient guidelines be updated?

DuPont Pioneer is funding research to determine if nutrient recommendations established almost 50 years ago should still be followed to fit current soybean genetics and management practices.

Through the Pioneer Crop Management Research Awards project, Shawn Conley, University of Wisconsin-Extension soybean specialist, and Adam Gaspar, UW graduate student, will study nutrient usage in soybeans.

“The goal is to see if plants are using more nutrients or using them at different times than the older research indicates,” Conley says. “If nutrient needs are different today, we can develop up-to-date recommendations for growers.”

Many of today’s nutrient recommendations for soybeans come from research conducted in the 1960s and 1970s, Conley said.

Among the nutrients the team will measure are potassium, phosphorus, sulfur, zinc, boron and manganese. The three-year project will require the collection and review of a large amount of data from fields in Wisconsin, Michigan and Minnesota—a process that Gaspar will spearhead. They’ll sample plant tissues (stems, petioles, leaves, pods, seeds and fallen leaves and petioles) to analyze nutrient partitioning throughout the growing season.

“One reason the industry hasn’t updated nutrients recommendations is that the research is difficult and costly,” Conley said. “DuPont Pioneer is funding this project and Gaspar’s time. Pioneer is also providing germplasm to help us determine how today’s varieties are using nutrients. The Wisconsin Soybean Marketing Board also is contributing significant support for this work. Collaborations like this help us provide better information to growers.”

Growers expect more from soybeans today. “While they’re not going to produce 100 bushels per acre in all environments, it’s clear they’re managing for overall higher yields. We need to see if nutrient availability may be limiting yields,” he said.

Pioneer initiates eight to 10 new CMRA projects with university researchers each year. The goal is to help provide additional agronomic information to its customers to help them get the greatest value from each acre.