Neonicotinoid seed treatments of soybean provide negligible benefits to US farmers

Authors

Spyridon Mourtzinis, University of Wisconsin-MadisonFollow
Christian H. Krupke, Purdue UniversityFollow
Paul D. Esker, Pennsylvania State UniversityFollow
Adam J. Varenhorst, South Dakota State UniversityFollow
Nicholas J. Arneson, University of Wisconsin-Madison
Carl A. Bradley, University of KentuckyFollow
Adam M. Byrne, Michigan State UniversityFollow
Martin I. Chilvers, Michigan State UniversityFollow
Loren Giesler, University of Nebraska-LincolnFollow
Ames Herbert, Virginia TechFollow
Yuba R. Kandel, Iowa State UniversityFollow
Maciej J. Kazula, University of MinnesotaFollow
Catherine Hunt, Iowa State University
Laura E. Lindsey, The Ohio State UniversityFollow
Sean Malone, Virginia TechFollow
Daren S. Mueller, Iowa State UniversityFollow
Seth Naeve, University of MinnesotaFollow
Emerson Nafziger, University of IllinoisFollow
Dominic D. Reisig, North Carolina State UniversityFollow
William J. Ross, University of ArkansasFollow
Devon R. Rossman, Michigan State University
Sally Taylor, Virginia TechFollow
Shawn P. Conley, University of Wisconsin-MadisonFollow

ORCID IDs

Paul D. Esker http://orcid.org/0000-0002-7753-3476

Carl A. Bradley http://orcid.org/0000-0002-8334-0750

Date of this Version

9-9-2019

Citation

Scientific Reports (2019) 9:11207

https://doi.org/10.1038/s41598-019-47442-8

Comments

This article is licensed under a Creative Commons Attribution 4.0 International License

Abstract

Neonicotinoids are the most widely used insecticides worldwide and are typically deployed as seed treatments (hereafter NST) in many grain and oilseed crops, including soybeans. However, there is a surprising dearth of information regarding NST effectiveness in increasing soybean seed yield, and most published data suggest weak, or inconsistent yield benefit. The US is the key soybean-producing nation worldwide and this work includes soybean yield data from 194 randomized and replicated field studies conducted specifically to evaluate the effect of NSTs on soybean seed yield at sites within 14 states from 2006 through 2017. Here we show that across the principal soybean-growing region of the country, there are negligible and management-specific yield benefits attributed to NSTs. Across the entire region, the maximum observed yield benefits due to fungicide (FST = fungicide seed treatment) + neonicotinoid use (FST + NST) reached 0.13 Mg/ha. Across the entire region, combinations of management practices affected the effectiveness of FST + N ST to increase yield but benefits were minimal ranging between 0.01 to 0.22 Mg/ha. Despite widespread use, this practice appears to have little benefit for most of soybean producers; across the entire region, a partial economic analysis further showed inconsistent evidence of a break-even cost of FST or FST + N ST. These results demonstrate that the current widespread prophylactic use of NST in the key soybean-producing areas of the US should be re-evaluated by producers and regulators alike.