In 2016 and 2017, Cheryl Trueman compared several different cucumber downy mildew control programs in plots at the University of Guelph Ridgetown Campus.
Different product rotations included:
- Bravo-only applied 6 times.
- A high input strategy that focused on optimal control and resistance management: Orondis Ultra A+B; Torrent; Zampro; Orondis Ultra A+B; Torrent; Zampro.
- A low-input strategy that focused on early control and resistance management, switching to lower-cost fungicides in the final weeks of harvest: Orondis Ultra A + B (plus Bravo); Torrent; Zampro; Bravo; Bravo; Bravo.
- A single application of Orondis Ultra, applied early followed by the other targeted downy mildew fungicides (Orondis Ultra A + B; Torrent ; Zampro; Torrent; Zampro; Torrent).
- Control – no fungicides applied.
Under these conditions final yields for both the high input and single Orondis Ultra (in rotation) were both significantly higher than the Bravo only programs and yield for the high input program were significantly higher than all other treatments.
When pressure was moderate in 2017, the high input and single Orondis Ultra in rotation program were very effective. All fungicide programs except Bravo only increased both fruit number and yield by weight.