Nozzle and Carrier Application Effects on Control of Soybean Leaf Spot Diseases

Increased soybean foliar disease potential has heightened grower interest in fungicide application techniques. Application field trials comparing application rate [187 vs. 112 L/ha (20 vs. 12 gal/acre)], nozzle style (twin-orifice; single-orifice) and spray quality (fine vs. medium and coarse spray quality), and application technique (with and without air-assist) along with an unsprayed check were done at two locations over two years. Fungicide deposition (coverage and droplet size) and disease severity in the bottom, middle, and top parts of the plant canopy, and soybean yield were measured.