Database Research Summaries
2017 Evaluation of Multiple Agronomic Considerations with Harvest Aid Use in Mississippi Soybean Production

calendar_today Year of Research: 2017
update Posted On: 12/04/2019
group John Orlowski (Principal Investigator, Mississippi State University, DREC)
bookmark Mississippi Soybean Promotion Board

Research Focus

The focus of the research was not provided.


  • Investigate the effects of different adjuvants on harvest aid performance.
  • Investigate the effects of spray volume on the efficacy of various soybean harvest aids.
  • Investigate the effects of harvest interval after harvest aid use on soybean yield, seed moisture content and shattering.
  • Determine the effect of various rates of paraquat on soybean at multiple growth stages to simulate issues with spray tank contamination and drift.


  1. The harvest aid products used in this study and applied alone did not affect soybean seed yield in either year when compared to each other and the untreated control (UTC).
  2. Yield results from this two-year study indicate that Gramoxone applied alone and with no adjuvant is the best product to use for defoliating soybeans prior to harvest.
  3. Overall, Gramoxone applied alone resulted in the most cost-efficient and effective defoliation in both years.
  4. Yield losses from delayed harvest in this study were not significant until well after the end of the PHI for Gramoxone that can be applied at R6.5.
  5. Gramoxone has the longest PHI of 15 days. If this product is the earliest allowed time to prevent yield loss (R6.5), then this 15-day waiting period will end soon after R8 or maturity. Thus, a properly timed application of Gramoxone as a harvest aid will not cause a delay in harvest beyond the time of harvest maturity. If harvest is delayed because of inclement weather, then some yield loss will occur whether or not a harvest aid was applied.


This research is important as it provides evidence of the response to effects on the harvests.

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

Funded in part by the soybean checkoff.