Corn Yield Response to DuPont™ Aproach® Prima Fungicide in the Southern U.S.
Agronomy Research Update
From Pioneer Agronomy Sciences
Key Findings
- Averaged over 7 locations and 29 paired comparisons, corn treated with Aproach Prima fungicide yielded 11 bu/acre more than non-treated corn (Figure 1).
- Aproach Prima fungicide applied at the VT-R1 growth stage produced positive economic returns in 19 of 29 comparisons or 66% of the time (Figure 2).
- Yield responses to Aproach Prima fungicide ranged from 10 bu/acre with Pioneer hybrid P1739YHR to over 30 bu/acre with Pioneer hybrid P1197YHR . On average, a positive economic return occurred with all hybrids evaluated (Figure 3).
Objective
- Evaluate corn yield response to DuPont™ Aproach® Prima fungicide applied at the VT-R1 growth stage on Pioneer® brand corn hybrids.
Study Description
Plot Layout:
On-farm strip trials
Locations:
7 (Ala., Ark., Ga., Ky., Miss.)
Year:
2015
Fungicide Treatment¹:
- Aproach Prima fungicide (6.8 fl oz/acre at VT-R1) Non-treated control
- Non-treated control
Pioneer brand corn hybrids:
Hybrid/Brand²:
- P1197YHR (YGCB, HX1, LL, RR2)
- P1637YHR (YGCB, HX1, LL, RR2)
- P1739YHR (YGCB, HX1, LL, RR2)
- P1916YHR (YGCB, HX1, LL, RR2)
Data Collected: Corn yield (bu/acre)
¹Do not exceed 6.8 fl.oz/A per crop. Don’t tank mix with an adjuvant (e.g. crop oil concentrate) when spraying between the V8 -- VT corn growth stage. The minimum retreatment interval in corn is 7 days. The minimum time (PHI) between application and harvest for grain or ear is 30 days and for silage is 20 days.
²All Pioneer products are hybrids unless designated with AM1, AM, AMRW, AMX, AMT, and AMXT, in which case they are brands.
Fungicide Treated
Pioneer® hybrid P1916YHR treated with 6.8 fl oz/acre of DuPont Aproach Prima fungicide on July 16, 2015 near Winchester, Ark. Application was made using a spray volume of 7 gal/acre by air at the R2 corn growth stage.
Southern rust pressure was low at the time of application but increased in severity and ultimately caused premature death in the non-treated check before the end of the season. Using a 1-9 scale where 1 = no infection and 9 = nearly all foliage covered with rust pustules and premature death, Aproach Prima fungicide-treated strips were rated 4 on average compared to non-treated strips which were rated 7.
Results
Figure 1. Average yield of corn treated with Aproach Prima fungicide at the VT-R1 corn growth stage and non-treated corn.
Data averaged over 7 locations and 29 paired comparisons from Ala., Ark., Ga., Ky., and Miss. & Tenn. in 2014-15.
Figure 2. Corn yield response to Aproach Prima fungicide applied at the VT-R1 corn growth stage by location and hybrid.
Data represent 7 locations and 29 paired comparisons from Ala., Ark., Ga., Ky. and Miss. & Tenn. in 2014-15. Red dashed line represents the breakeven yield response of 6 Bu/A assuming a corn selling price of $3.75 per bushel.
Figure 3. Corn yield response to Aproach Prima fungicide applied at the VT-R1 corn growth stage by hybrid.
Data represent 3 locations and 14 paired comparisons from Ark. and Miss. in 2015. The number of observations by hybrid vary. Red dashed line represents the breakeven yield response of 6 bu/acre assuming a corn selling price of $3.75 per bushel.
Summary
Corn ear leaves infested with Southern Rust in 2014 near Camilla, Ga. Non-treated leaf (top), Aproach Prima fungicide 6.8 fl oz/acre at V8 (middle) and Aproach Prima fungicide 6.8 fl oz/A at V8 fb 6.8 fl oz/A at R1 (bottom).
*For research purposes only. Sequential spray programs of this nature should utilize DuPont™ Aproach® fungicide at a rate of 3-6 fl oz/acre followed by Aproach Prima fungicide at a rate of 6.8 fl oz/acre. Aproach Prima fungicide can only be applied once per growing season according to label instructions.
The foregoing is provided for informational use only. Please contact your Pioneer sales professional for information and suggestions specific to your operation. 2015 data are based on average of all comparisons made in seven locations through Nov. 16, 2015. Multi-year and multi-location is a better predictor of future performance. Do not use these or any other data from a limited number of trials as a significant factor in product selection. Product responses are variable and subject to a variety of environmental, disease, and pest pressures. Individual results may vary.
YGCB,HX1,LL,RR2 (Optimum® Intrasect®) - Contains the YieldGard® Corn Borer gene and Herculex® I gene for resistance to corn borer. Herculex® I Protection technology by Dow AgroSciences and Pioneer Hi-Bred. Herculex® and the HX logo are registered trademarks of Dow AgroSciences LLC. YieldGard®, the YieldGard Corn Borer Design and Roundup® Ready are registered trademarks used under license from Monsanto Company. Liberty®, LibertyLink® and the Water Droplet Design are trademarks of Bayer.