Database Research Summaries
2017 Increasing Soybean Yield by Enhancing Seed Fill

calendar_today Year of Research: 2017
update Posted On: 12/04/2019
group Shaun Casteel (Principal Investigator, Purdue University)
bookmark Indiana Soybean Alliance

Research Focus

The focus of this project is to determine and to partition the effect of intense management (P and S supply factored with and without foliar protection) to enhance seed fill thereby, increasing yield.


  • Determine the duration and the rate of seed fill during late soybean development,
    especially after R6 (full seed) until harvest.
  • Determine the opportunities to enhance seed fill (e.g., higher daily gain, extended seed
    fill duration) and thus, improve grain yield through synergies in nutrient supply and foliar protection.


  1. The greatest yield response in the MG II study was in the combination of enhanced fertility (sulfur and phosphorus) plus the prophylactic application of fungicide and insecticide (i.e., TSP+AMS+R4).
  2. During the MG III study, the greatest yield effect in 2016 was TSP+AMS+R4. However, the source of yield improvement seems to be more related seed growth rate (SGR) than the duration of the effective seed filling period. Little differences were noted in 2017, therefore, no major yield improvements were noted.
  3. Preliminary conclusions are that the combination of enhanced fertility (sulfur and phosphorus) and foliar protection provided greater benefit to the shorter season varieties than the fuller season varieties.


  • This project will increase opportunities to enhance seed fill and improve grain yield.

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

Funded in part by the soybean checkoff.