Trial Objective

• Prosaro^® PRO is a new foliar fungicide for Western Canada that combines three active ingredients to protect wheat, barley, oats, and triticale against leaf and head diseases in high-disease environments.
• Prosaro^® PRO foliar fungicide contains tebuconazole (the fast-acting leaf disease specialist), prothioconazole (prolonged action for longer residual control), and fluopyram (a new group 7 active ingredient that provides fast-acting and residual protection for leaf and head diseases).
• The objective of these trials was to evaluate Prosaro^® PRO foliar fungicide in wheat for yield and quality protection compared to an untreated check and a competitor fungicide at T3 application timing in wheat in 2020 and 2021.

Experiment/Trial Design

• Research Site Details:
  • 53 locations throughout Western Canada from the Market Development Representative (MDR) and Market Development Agronomist (MDA) trial programs in 2020 and 2021.
  • MDR trials were applied in a replicated strip format with Bayer-owned equipment.
  • MDA trials were applied in a replicated strip format with grower equipment.
  • Trial fields were evaluated for variability using field health imagery from Climate FieldView™. Only fields with relatively low variability across the trial area were used.
  • All aspects of field management within the trial area were consistent except for the fungicide treatment.
• Trial Design:
  • Fungicide treatments were applied according to the label at the optimal head timing (T3 – when 75% of the wheat heads on the main stem are fully emerged to when 50% of wheat heads on the main stem are flowering).
  • Treatments included:
    • Untreated check
    • Prosaro^® PRO foliar fungicide + NIS (non-ionic surfactant)
    • Miravis^® Ace fungicide + NIS
  • Leaf disease assessments were conducted at the time of application and 10 to 14 days after application timing.
  • Treatments were harvested and weighed with a weigh wagon to determine yield.
  • At harvest, grain samples were taken from each treatment rep and evaluated for common grain quality parameters.
• Data Quality and Summary:
  • Yield and grain quality data were assessed for quality by checking the overall trial CV (coefficient of variance) and the CV between reps for each trial location. Only trials with a CV of less than 10 were used in data summaries.
  • A balanced data summary from the MDR and MDA programs in 2020 and 2021 was pulled to compare the yield and quality performance of Prosaro^® PRO to the untreated check and competitor.

Understanding the Results

• Environmental Considerations:
  • 2020 had generally good moisture conditions across the west. Above-average to average precipitation in Alberta and Northwest Saskatchewan. Average to below-average precipitation in Saskatchewan and Manitoba (Figure 2).
  • Overall disease pressure in the trials was low to normal in 2020.
  • 2021 was an extreme drought for much of the west (Figure 3).
  • Overall disease pressure in the trials was nonexistent.
• Performance:
  • The two-year summary of 53 trials shows there was a noticeable yield advantage for a fungicide application at the T3 timing in wheat compared to untreated.
  • The untreated check averaged 61.6 bu/acre (4142.67 kg/hectare), the Prosaro^® PRO foliar fungicide + NIS treatment averaged 65.6 bu/acre (4411.67 kg/hectare), and the Miravis^® Ace fungicide + NIS treatment averaged 65.9 bu/acre (4431.85 kg/hectare) (Figure 4).
  • The Prosaro^® PRO foliar fungicide + NIS treatment and Miravis^® Ace fungicide + NIS treatment had similar average yields (Figure 4).
• Fusarium was found in the grain samples from the 2020 trials.
  • A fungicide treatment reduced the % FDK (Fusarium-damaged kernels) in the grain samples compared to the untreated check. However, the % FDK for the untreated check was low enough to fall under No. 1 Canadian Western Spring Wheat (CWRS) (Table 1). No grade improvements were gained from a fungicide treatment due to low overall disease pressure.
  • The % FDK in the Prosaro^® PRO foliar fungicide + NIS treatment sample and in the Miravis^® Ace fungicide + NIS treatment sample were similar and less than the level found in the untreated check treatment sample (Figure 5).
• Not surprising, Fusarium was not found in the grain samples from the 2021 trials because of very low disease pressure due to the extreme drought.

Key Learnings

• A positive yield response in wheat could be seen from a Prosaro^® PRO foliar fungicide T3 application compared to the untreated check in the two years (2020, 2021) under lower-than-normal precipitation and disease pressure.
  • Assuming suggested prices of $6/bu for wheat and $5/acre for application cost, the fungicide application broke even.
• Prosaro^® PRO foliar fungicide is a premium fungicide that is targeted towards average to above-average disease pressure fields. These trials showed Prosaro^® PRO foliar fungicide has a positive effect on yield and quality even in drier, lower disease pressure years.
• We look forward to a more ‘normal’ precipitation year to show how Prosaro^® PRO foliar fungicide protects against tough wheat leaf and head diseases.