Submitted to: International Journal of Agricultural and Biosystems Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/10/2018
Publication Date: 6/7/2018
Citation: Martin, D.E., Latheef, M.A., McCracken, A. 2018. Aerial application methods for increasing fungicide deposition on corn. International Journal of Agricultural and Biosystems Engineering. 3(4):92-102.
Interpretive Summary: Field studies were conducted to determine the spray deposition characteristics of fungicide on field corn using low volume spray rates in conjunction with electrostatic, rotary and conventional nozzles in order to optimize aerial application methods for control of foliar diseases. It was determined that one particular rotary atomizer yielded superior performance over all other nozzles and that the electrostatic nozzle at 1 gallon per acre performed just as well as conventional nozzles applying twice the rate. The results from this study will help aerial applicators select appropriate nozzles for fungicide applications and could double application productivity by enabling low-volume aerial applications which save time and fuel.
Technical Abstract: Aerial application methods for fungicide sprays on corn, Zea mays L., were evaluated on a commercial farm in Texas. The fungicide was applied to corn grown in a center pivot irrigation system using conventional, rotary, and electrostatic nozzles in combination with two spray rates of 10 and 19 L/ha. Fungicide deposits were measured using a fluorescent dye tracer collected on artificial samplers and corn foliage. Spray droplets deposited on water sensitive paper samplers described volume median diameter (Dv0.5), droplet density, percent spray coverage and application rate. AU5000 rotary atomizers at 19 L/ha delivered significantly greater dye tracer deposits on artificial samplers and corn foliage compared to other nozzles in both top and mid canopy regions. Similarly, deposition as demonstrated by application rate on water sensitive paper samplers for AU5000 atomizers was twice as much as that for conventional nozzles at similar spray rates in both top and mid canopy positions. Electrostatic nozzles at 10 L/ha produced deposits comparable to conventional hydraulic nozzles at 19 L/ha. Results indicated that AU5000 rotary nozzles at 19 L/ha with medium size droplets, greater droplet density and increased deposition appear to be an optimal spray treatment for improving fungicide deposition on corn foliage to control foliar diseases.