High-Input Management Systems Effect on Soybean Seed Yield, Yield Components, and Economic Break-Even Probabilities

Elevated soybean [Glycine max (L.) Merr. ] prices have spurred interest in maximizing soybean seed yield and has led growers to increase the number of inputs in their production systems. However, little information exists about the effects of high-input management on soybean yield and profitability. The purpose of this study was to investigate the effects of individual inputs, as well as combinations of inputs marketed to protect or increase soybean seed yield, yield components, and economic break-even probabilities. Studies were established in nine states and three soybean growing regions (North, Central, and South) between 2012 and 2014. In each site-year both individual inputs and combination high-input (SOYA) management systems were tested. When averaged between 2012 and 2014, regional results showed no seed yield responses in the South region, but multiple inputs affected seed yield in the North region. In general, the combination SOYA inputs resulted in the greatest yield increases (up to 12%) compared to standard management, but Bayesian economic analysis indicated SOYA had low break-even probabilities. Foliar insecticide had the greatest break-even probabilities across all environments, although insect pressure was generally low across all site-years. Soybean producers in North region are likely to realize a greater response from increased inputs, but producers across all regions should carefully evaluate adding inputs to their soybean management systems and ensure that they continue to follow the principles of integrated pest management. J.M. Orlowski, Delta Research and Extension Center, Mississippi State Univ., 82 Stoneville Road, Stoneville, MS 38776; B.J. Haverkamp and K.L. Roozeboom, Dep. of Agronomy, Kansas State Univ., 1712 Claflin Road, Manhattan, KS 66506; R.G. Laurenz and K.D. Thelen, Dep. of Plant, Soil, and Microbial Sciences, Michigan State Univ., 1066 Bogue Street, East Lansing, MI 48824; D.A. Marburger and S.P. Conley, Dep. of Agronomy, Univ. of Wisconsin-Madison, 1575 Linden Drive, Madison, WI 53706E; E.W. Wilson and S.L. Naeve, Dep. of Agronomy and Plant Genetics, Univ. of Minnesota-Twin Cities, 1991 Upper Buford Circle, St. Paul, MN 55108; S.N. Casteel, Dep. of Agronomy, Purdue Univ., 915 West State Street, West Lafayette, IN 47907; E.D. Nafziger, Dep. of Crop Sciences, Univ. of Illinois at Urbana-Champaign, 1102 South Goodwin Avenue, Urbana, IL 61801; W.J. Ross, Dep. of Crop, Soil, and Environmental Sciences, Univ. of Arkansas, PO Box 391, Little Rock, AR 72203; and C.D. Lee, Dep. of Plant and Soil Sciences, Univ. of Kentucky, 1405 Veterans Drive, Lexington, KY 40546. Received 9 Oct. 2015. Accepted 5 Apr. 2016. Assigned to Associate Editor Shawn Kaeppler. *Corresponding author ( john.orlowski@msstate.edu). Abbreviations: IPM, integrated pest-management; LCO, lipo-chitooligosaccharide; SOYA, high-input management system consisting of a seed treatment fungicide, insecticide, inoculant, lipo-chitooligosaccharide, nitrogen fertilizer, foliar lipo-chitooligosaccharide, foliar fertilizer, antioxidant, foliar fungicide, and foliar insecticide; SP, standard practice (current university recommendations for fertilizer and herbicide programs). Published in Crop Sci. 56:1988–2004 (2016). doi: 10.2135/cropsci2015.10. 0620 © Crop Science Society of America | 5585 Guilford Rd., Madison, WI 53711 USA This is an open access article distributed under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Published May 27, 2016