Fungicides are the only management tool presently available to manage Asian soybean rust. The fungicides currently registered for use on soybean (Section 3 and Section 18 labels) have little systemic movement, if any, within a leaf, especially when compared with systemic herbicides. Thus, fungicide efficacy depends on application timing, dosage, and perhaps most important, coverage and penetration. Droplet size, volume, and pressure influence coverage and penetration of the fungicide in the soybean canopy.
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