Corn Hybrid Response to Foliar Fungicide Application – 2025

• Evaluate fungicide yield response across diverse environments — quantify the magnitude and consistency of fungicide yield response across 32 field locations.
• Identify hybrid-specific fungicide response patterns — determine which seed products show the greatest yield advantage from fungicide application.
• Assess geographic and agronomic factors — understand how latitude, planting timing, CRM and drainage class impact the magnitude of fungicide yield advantage.

• Year: 2025
• Locations: 32 trial sites across IA, MN, WI, IN, OH, IL, SD, NE, MI, and ND (Figure 1)

  

  Figure 1. Trial locations of the 32 field sites from the study, 2025.

• Planting Window: April 13 – June 2, 2025
• Experimental Design: Split-plot comparing treated vs. untreated check
• Hybrids Evaluated: 90+ Pioneer^® brand corn products across all locations; 78-day to 118-day RM (avg. 16 hybrids per location)
• Fungicides: Forcivo™ (24 locations), Aproach^® Prima (1 location), competitive 3-way (1 location), Not specified (6 locations)
• Application Timing: VT to R1 growth stage
• Data Collected: Grain yield adjusted to 15.5% moisture

Overall Response to Fungicide Application

• Foliar fungicide application provided reliable yield protection across the trial network in 2025 — a year marked by significant disease pressure including a southern rust outbreak that pushed further north than typical (Figure 2).

  

  Figure 2. Southern rust disease risk across the U.S. Corn Belt in August of 2025, generated from the Corteva Disease Risk Model.

• On average, locations had a positive response to fungicide application with a 90% win rate.
• The average yield response of hybrids treated with fungicide relative to their untreated check was +14.2 bu/A.

  Table 1. Average response to fungicide treatment and yield advantage over the untreated check (UTC), 2025.

  Response	Trials	Value
  Positive	29	90%
  Negative	3	9%
  Avg. Yield Advantage	32	+14.2 bu/acre

2025 Disease Pressure

• The 2025 growing season featured atypical disease pressure across much of the trial footprint. A southern rust outbreak — confirmed across multiple states by late July — combined with tar spot, gray leaf spot and northern corn leaf blight to create conditions highly favorable for fungicide response.

Win Rate by Latitude Zone

• North Central and Southern zones showed highest win rates — 100% win rate in both zones (14 combined trials) across N. Iowa, S. Wisconsin, S. Indiana, S. Ohio and C. Illinois.
• Central zone delivered strong results with largest sample size — 90% win rate across 10 trials in C. Iowa, N. Indiana, N. Ohio and Nebraska provides highest confidence estimate.
• Northern zones showed more variable response — Upper Midwest (80%) and Far North (67%) win rates suggest short-season environments and reduced disease pressure limit fungicide ROI.
• All zones remained above 67% win rate — fungicide application is broadly beneficial across the geography.

  Table 2. Average response to fungicide treatment and yield advantage over the untreated check (UTC), 2025.

  Latitude	Region	Trials	Yield Response (bu/A)
  <40°N	Southern (IN, OH, IL)	5	18.7
  40-42°N	Central (IA, IN, OH, NE)	10	11.2
  42-44°N	North Central (IA, WI)	9	21.3
  44-45°N	Upper Midwest (MN, SD, WI)	5	14.6
  >45°N	Far North (ND)	3	8.4

15 Hybrids with Greatest Yield Response to Fungicide

• Fungicide yield protection ranged from +10 to +37 bu/A among the most responsive hybrids — Table 3 ranks the top 15 products by average yield advantage across locations.

  Table 3. 15 hybrids with the greatest fungicide yield response, ranked by win rate. Win rate = percentage of locations where fungicide outyielding UTC. Only includes hybrids tested at > 4 locations.

  Seed Product	Wins	Locs	Win Rate	Average Response (bu/A)
  P12517V (V,LL,RR2,ENL)	9	9	100%	36.8
  P1027AM (AM,LL,RR2)	6	6	100%	33.6
  P12065Q (Q,LL,RR2)	7	7	100%	25.1
  P11056V (V,LL,RR2,ENL)	7	7	100%	22.4
  P10625V (V,LL,RR2,ENL)	6	6	100%	19.7
  P13050V (V,LL,RR2,ENL)	5	5	100%	18.3
  P08527V (V,LL,RR2,ENL)	9	10	90%	21.2
  P10300PCE (PW,ENL,RIB)	7	8	88%	24.6
  P02405V (V,LL,RR2,ENL)	14	16	88%	12.8
  P03115V (V,LL,RR2,ENL)	10	12	83%	10.2
  P0859AM (AM,LL,RR2)	10	13	77%	14.1
  P13777PCE (PW,ENL,RIB)	6	8	75%	11.5
  P05737PCE (PW,ENL,RIB)	8	11	73%	15.3
  P014830Q (Q,LL,RR2)	10	14	71%	13.7
  P98125V (V,LL,RR2,ENL)	10	14	71%	12.9

• Six hybrids showed consistent yield protection across all locations tested — P12517V (+36.8 bu/A), P1027AM (+33.6 bu/A), P12065Q (+25.1 bu/A), P11056V (+22.4 bu/ A), P10625V (+19.7 bu/A) and P13050V (+18.3 bu/A) responded positively at every trial site.
• All top 15 hybrids averaged at least +10 bu/A yield protection — reinforcing the value of scouting and targeted fungicide application when disease risk is present.

15 Hybrids with Least Yield Response to Fungicide

• Bottom 15 hybrids showed smaller and more variable yield response to fungicide — averaging +2 to +9 bu/A, with several hybrids showing near-zero average response across locations (Table 4).

  Table 4. 15 hybrids with the smallest fungicide yield response, ranked by win rate. Win rate = percentage of locations where fungicide outyielding UTC. Only includes hybrids tested at > 4 locations.

  Seed Product	Wins	Locs	Win Rate	Average Response (bu/A)
  P12517V (V,LL,RR2,ENL)	10	15	67%	8.7
  P1027AM (AM,LL,RR2)	9	14	64%	11.2
  P12065Q (Q,LL,RR2)	6	10	60%	5.8
  P11056V (V,LL,RR2,ENL)	4	7	57%	9.4
  P10625V (V,LL,RR2,ENL)	4	7	57%	6.2
  P13050V (V,LL,RR2,ENL)	4	7	57%	4.9
  P08527V (V,LL,RR2,ENL)	3	6	50%	3.1
  P10300PCE (PW,ENL,RIB)	4	8	50%	-2.1
  P02405V (V,LL,RR2,ENL)	4	8	50%	4.3
  P03115V (V,LL,RR2,ENL)	5	10	50%	-0.8
  P0859AM (AM,LL,RR2)	2	4	50%	1.7
  P13777PCE (PW,ENL,RIB)	3	6	50%	7.9
  P05737PCE (PW,ENL,RIB)	3	6	50%	6.4
  P014830Q (Q,LL,RR2)	2	5	40%	-1.4
  P98125V (V,LL,RR2,ENL)	2	5	40%	5.7

• Lower response does not necessarily indicate stronger disease tolerance — differences may reflect lower disease pressure at trial locations, fewer observations or other environmental factors rather than inherent hybrid resistance.
• These hybrids may still benefit from fungicide under the right conditions — individual location results varied widely within this group, and growers should rely on local scouting and disease forecasts rather than assuming fungicide is unnecessary.

• Fungicide application provided meaningful yield protection across most trial locations in 2025 — average yield advantage of +14.2 bu/A across 32 locations, with 28 of 32 locations showing a positive response. The 2025 average exceeded the long-term trial average of +7.4 bu/A (Jeschke, 2025) as well as published meta-analysis estimates of +6-7 bu/A for dual mode of action (MOA) products and +9 bu/A for triple MOA products (Paul et al., 2011; Wise et al., 2019), consistent with elevated southern rust and other disease pressure observed across the Corn Belt in 2025.
• Yield response varied by hybrid — the most responsive hybrids averaged +26.0 bu/A while the least responsive showed near-zero average response. Observed differences reflect a combination of disease pressure at trial locations, hybrid genetic resistance profiles, and environmental factors, and should not be interpreted solely as a measure of hybrid disease susceptibility.
• Geography influenced fungicide yield response — the North Central zone (N. Iowa, S. Wisconsin) showed the strongest response, likely reflecting both elevated disease pressure and the highest concentration of trials in this region. Initial analysis suggested CRM and planting date also influenced response, but when examined within a geographically controlled subset of Iowa locations, these effects were not distinguishable from geographic variation and were therefore excluded from the final analysis.
• Results reinforce the value of in-season scouting and disease risk tools — fungicide response was not uniform across locations or hybrids, underscoring the need for site-specific decision-making using tools such as the Corteva Disease Risk Model to identify fields and conditions most likely to benefit from application. 

• Jeschke, M. 2025. Maximizing the Value of Foliar Fungicides in Corn. Pioneer Crop Insights Vol. 35 No. 5. Corteva Agriscience. Johnston, IA.
• Paul, P.A., L.V. Madden, C.A. Bradley, A.E. Robertson, G.P. Munkvold, G. Shaner, K.A. Wise, D.K. Malvick, T.W. Allen, A. Grybauskas, P. Vincelli, and P. Esker. 2011. Meta-analysis of yield response of hybrid field corn to foliar fungicides in the U.S. Corn Belt. Phytopathology 101:1122- 1132.
• Wise, K.A., D. Smith, A. Freije, D.S. Mueller, Y. Kandel, T. Allen, C.A. Bradley, E. Byamukama, M. Chilvers, T. Faske, A. Friskop, C. Hollier, T.A. Jackson- Ziems, H. Kelly, R. Kemerait, P. Price III, A. Robertson, and A. Tenuta. 2019. Meta-analysis of yield response of foliar fungicide-treated hybrid corn in the United States and Ontario, Canada. PLoS One 14:e0217510.