Soybean Yield Response to In‐furrow Fungicides, Fertilizers, and Their Combinations

Abstract

Core Ideas Fungicide in‐furrow and starter fertilzer individually did not increase yield. Fungicide and starter fertilizer combined in‐furrow increased yield marginally. Fungicide and starter fertilizer in‐furrow may not be economical without disease. Planting into cool and wet conditions exposes soybean [Glycine max (L.) Merr.] seed and seedlings to pathogens that may reduce plant populations, resulting in lower yield. Recently, fungicides have been labeled for in‐furrow applications and marketed to provide additional broad‐spectrum protection from soilborne fungi and enhance seedling vigor. Additionally, liquid fertilizers have been promoted recently as a carrier for fungicides to improve yield in some soybean producing areas in the United States. The objective of this study was to evaluate the effect of a fungicide, starter fertilizer, and a combination of fungicide and starter fertilizer on soybean yield. Field experiments were laid out in Arkansas, Indiana, Iowa, and Mississippi in the United States and Ontario, Canada, with a total of 14 site‐years. A positive yield response was observed with the fungicide and starter fertilizer treatment combination in Arkansas in 2014; however, there was no effect of treatment on soybean yield at any other location or year. Overall, a yield benefit of 1.6 bu/acre (107.6 kg/ha) (P = 0.02) with the fungicide and starter fertilizer treatment was observed across all locations when combined using meta‐analysis. In conclusion, our study suggests that the prophylactic application of fungicide and starter fertilizer may not be profitable without the risk of soilborne diseases and nutrient deficiencies.