Evaluation of various spraying equipment for effective application of fungicides to control Asian soybean rust

Fungicides manufactured to control soybean rust are effective; however, successful control of this disease will mostly depend on proper application methods. Spray coverage and deposition from 9 application equipment/spray nozzles were analyzed. In general, the spray treatments with air assistance were more effective in spraying rust fungicides than the treatments with the conventional boom sprayer. Spray performances from the boom sprayer with a canopy opener were very similar to the air assisted spray treatments, and were better than other treatments with the boom sprayer. Twin jet, Turbo Dual pattern and hollow cone nozzles produced lower spray performances than conventional flat fan nozzles. For treatments with the boom sprayer, medium spray quality provided higher spray coverage inside canopies than coarse and fine spray qualities. Future research will address how much fungicide inside canopies can be sufficient to control the soybean rust disease.