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<div>Diverse plant pathogens have been suppressed by ultraviolet (UV) light, both alone and in combination with select portions of the visible light spectrum in recent studies. Stationary UVB lamps or UVB lamps borne on a slow-moving boom (e.g. 0.03 km/h) have been used to apply UV doses approximating 50 to 200 J/m²/day. Operational speeds closer to 3.0 km/h (100X the foregoing) are needed to adapt this technology to field applications involving conventionally driven tractors. Reciprocity of UVB effects extrapolated from longer exposure time/ lower intensity treatments were confirmed at target intensity and times for UVC field treatments. We used a dense reflectorized hemicylindrical array of multiple UVC fluorescent lamps to yield sufficient intensity and multiple reflectance angles to maximize exposure of all plant surfaces in preliminary trials in a commercial strawberry field in Florida. Dense arrays of high intensity red (663 nm peak irradiance) LEDs were required for synergistic activity with short-duration/high intensity UV treatments. Neither UVB fluorescent lamps nor currently available UV-LEDs produced sufficient energy in the biologically relevant wavebands (250 to 300 nm) to allow their use in units moving at speeds significantly above 0.06 km/h, but might be amenable for autonomous or robotic applications in field plantings at greatly reduced speeds.</div>