Economic risk and profitability of soybean fungicide and insecticide seed treatments at reduced seeding rate

Abstract

Earlier soybean [Glycine max (L.) Merr.] planting, increased seed costs, and higher commodity prices have led to a surge in the use of soybean fungicide and insecticide seed treatments, while recent studies have suggested that growers should consider lowering seeding rates to increase their return on investment. Ultimately, growers would like to know the value proposition of combining seed treatments with lowered seeding rates. Therefore, three seed treatments (untreated, ApronMaxx, and Cruiser-Maxx) and six seeding rates (98,800, 148,200, 197,600, 247,000, 296,400, and 345,800 seeds ha-1) were evaluated to determine seed yield, profitability, and economic risk of various seed treatments and seeding rates, including the economically optimal seeding rate (EOSR) for each seed treatment. Trials were conducted at nine locations throughout Wisconsin during the 2012 and 2013 growing seasons, totaling 18 site-years. Across a wide range of seeding rates, ApronMaxx provided no yield or profitability gains and only slight risk benefits (<0.54 break-even probability) at grain sale prices between $0.33 and $0.55 kg-1. CruiserMaxx increased yield by 12% at 98,800 seeds ha-1 and by 4% at 345,800 seeds ha-1. In addition, Cruiser- Maxx was able to substantially lower risk and increase profit at both reduced and recommended (197,000–345,800 seeds ha-1) seeding rates across a wide range of environments and grain sale prices. The lowest risk and largest average profit increase was always at the EOSR, which decreased as the grain sale price declined. At current seed costs, the EOSR for CruiserMaxx treated seed ranged from 232,000 to 261,000 seeds ha-1 depending on the grain sale price. These data indicate that producers should account for their expected grain sale price and seed treatment choice when determining seeding rates to reduce economic risk and increase profitability.