Database Research Summaries
Agronomic and Economic Evaluation of Soybean/Corn Rotation 1

calendar_today Year of Research: 2017
update Posted On: 05/23/2019
group M. Wayne Ebelhar. (Principal Investigator, Mississippi State University)
bookmark Mississippi Soybean Promotion Board

Research Focus

The focus of this research is to combine new technology into a management system that can optimize yields and increase profitability.


  • Determine the agronomic implications of soybean/corn rotations in twin-row planting systems under standard and high management with irrigation.
  • Evaluate the economic impact of the rotation systems and fertilizer management on whole-farm enterprise profitability.


  1. Studies were taken place on a Commerce sandy/silt loam site and a Sharkey clay site for six years. The studies were designed to evaluate corn and soybean performance when grown in 1 year soybean: 1 year corn (1:1) and 2 years soybean: 1 year corn (2:1) rotations. Each study included a standard fertility treatment (220 lb N/acre added to the corn crop and no P and K added to either crop) and a high fertility treatment that consisted of 260 lb N/acre added to corn and 26.2 lbP/acre and 50 lb K/acre added to both crops.
  2. On the Commerce soil site, corn grown in the 1:1 rotation with soybean in both the standard and high fertility treatment yielded 8-11 bu/acre more than corn grown following a second year of soybeans. Corn yields from the high fertility treatment exceeded yields from standard fertility treatment by 25-28 bu/acre. Soybean yields were not different between standard and high fertility treatments. Therefore, adding this fertility would have been unprofitable.
  3. Corn yields following either one or two years of soybeans were similar in both fertility treatments at the Sharkey clay site. The corn high fertility treatment increased the yield by 12-14 bu/acre. Soybean yields following either corn or the second year of soybeans in the rotation scheme were nearly identical in both fertility treatments. Soybean yields were not different between the two fertility treatments and would have been unprofitable.


  • Adoption of crop rotation will enable producers to increase soybean yields, increase corn yields, and also increase profitability.
  • The use of rotation will greatly reduce the spread of resistant weeds by offering multiple crops for rotating herbicides.

For more information about this research project, please visit the National Soybean Checkoff Research Database.

Funded in part by the soybean checkoff.