Corn Hybrid Selection

Hybrid selection is crucial to establishing productive stands and achieving high yields. Hybrids have specific strengths that could make one a top-performing choice for a certain environment but a lower performer in a different environment. Selecting a diverse lineup of locally adapted hybrids that vary in maturity and agronomic strengths can help growers lower their risk of crop loss. Hybrids should be considered/selected for the following key traits: maturity, yield, drought tolerance, standability, pest resistance, drydown, grain quality and harvestability.

Hybrid Drought Tolerance

Hybrid drought tolerance can be a major factor in determining yield in water-limited conditions. Pioneer® brand Optimum® AQUAmax® hybrids help growers minimize risk and maximize their productivity under drought stress. DuPont Pioneer researchers evaluated the performance of Optimum AQUAmax hybrids in 289 on-farm grower trials over 3 years in western regions of the Corn Belt. At an increased seeding rate, the Optimum AQUAmax hybrids outyielded the grower-selected hybrid and seeding rate in 221 of the 289 environments. The average yield advantage was 9.2 bu/acre.

Ears of an Optimum® AQUAmax® hybrid and a hybrid of similar maturity but with lower drought tolerance produced under significant drought stress at Johnston, Iowa, in 2012.

Figure 1. Ears of an Optimum AQUAmax hybrid (left) and a hybrid of similar maturity but with lower drought tolerance (right) produced under significant drought stress at Johnston, Iowa, in 2012.

Stress Emergence and High-Residue Suitability Ratings

DuPont Pioneer stress emergence and high-residue suitability ratings give guidance to growers selecting hybrids for early planting and reduced-tillage systems. Every year, Pioneer conducts extensive emergence trials under a wide range of stressful environments and soil types, including early-planted and reduced-tillage fields. Based on data from stressful locations as well as lab assays that mimic extreme cold stress, each hybrid is assigned a stress emergence score. This score helps characterize hybrids for their genetic potential to establish stands under stress conditions (Figure 2).

Relationship between early stand and stress emergence scores in stressful, high-residue locations in a two-year study.

Figure 2. Relationship between early stand and stress emergence scores in stressful, high-residue locations in a 2-year study.

Disease Resistance

Disease resistance is another important consideration when selecting hybrids. Pioneer® brand hybrids are rated on a scale of 1 to 9 for their level of resistance to major foliar diseases: 1-3 = susceptible, 4-5 = moderately susceptible, 6-7 = resistant, 8-9 = highly resistant. High-residue environments can be associated with greater disease pressure, making hybrid resistance more critical. The survival of diseases in corn residue can lead to earlier infection and higher disease incidence and severity in the subsequent corn crop. Extensive Pioneer research has consistently shown the importance of hybrid disease resistance in disease management (Figure 3).

Two hybrids showing different levels of foliar disease symptoms.

Figure 3. Two hybrids showing vastly different levels of foliar disease symptoms in a trial near Macomb, Ill., in 2009.

Finally, hybrid selection can be improved by matching a hybrid with the expected growing environment. Pioneer EnClass® soils is a new tool that optimizes product selection based on a hybrid’s response to a field’s soil/water characteristics. Because hybrids differ in their tolerance to high or low water availability and drainage, it’s important to take soil moisture and water-holding characteristics into account.

DuPont Pioneer corn research trials.

In 2012, DuPont Pioneer conducted research trials to examine how hybrids respond to various plant populations in soils with different levels of water availability using the Pioneer EnClass Soils system. Results from this study showed that the product yield responses can vary substantially among the Pioneer EnClass soils categories—potentially wet, well drained and wet/dry (Figure 4).

Response of Pioneer® P0062AM1™ brand corn (AM1, LL, RR2) and Pioneer® hybrid P1324HR (HX1, LL, RR2) to population and Pioneer EnClass soils categories.

Figure 4. Response of Pioneer® P0062AM1™ brand corn (AM1, LL, RR2) and Pioneer® hybrid P1324HR (HX1, LL, RR2) to population and Pioneer EnClass soils categories across 27 and 31 locations, respectively.

        
    
AM - Optimum® AcreMax® Insect Protection system with YGCB, HX1, LL, RR2. Contains a single-bag integrated refuge solution for above-ground insects. In EPA-designated cotton growing counties, a 20% separate refuge must be planted with Optimum AcreMax products.
YGCB,HX1,LL,RR2 (Optimum® Intrasect®) - Contains the YieldGard® Corn Borer gene and Herculex® I gene for resistance to corn borer. Herculex® I Insect 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.
HX1 - Contains the Herculex® I Insect Protection gene which provides protection against European corn borer, southwestern corn borer, black cutworm, fall armyworm, western bean cutworm, lesser corn stalk borer, southern corn stalk borer, and sugarcane borer; and suppresses corn earworm. Herculex® I Insect Protection technology by Dow AgroSciences and Pioneer Hi-Bred. Herculex® and the HX logo are registered trademarks of Dow AgroSciences LLC.
HXX – Herculex® XTRA contains both the Herculex I and Herculex RW genes. Herculex® XTRA Insect Protection technology by Dow AgroSciences and Pioneer Hi-Bred. Herculex® and the HX logo are registered trademarks of Dow AgroSciences LLC.
LL - Contains the LibertyLink® gene for resistance to Liberty® herbicide. Liberty®, LibertyLink® and the Water Droplet Design are trademarks of Bayer.
RR2 – Contains the Roundup Ready® Corn 2 gene. Roundup Ready® is a registered trademark used under license from Monsanto Company.

 

IMPORTANT: Trait rating scores provide key information useful in selection and management of Pioneer® brand products in your area. Information and ratings are based on comparisons with other Pioneer brand products, not competitive products. Information and scores are assigned by DuPont Pioneer Research Managers. Scores are based on period-of-years testing through 2012 harvest and were the latest available at time of printing. Some scores may change after 2013 harvest. Scores represent an average of performance data across areas of adaptation, multiple growing conditions, and a wide range of both climate and soil types, and may not predict future results. All products within a hybrid family receive the same score unless observations indicate a significant difference. Individual product responses are variable and subject to a variety of environmental, disease and pest pressures. Please use this information as only one component of your product positioning decision. Refer to www.pioneer.com/products or contact a Pioneer sales professional for the latest and most complete listing of traits and scores for each Pioneer brand product and for product placement and management suggestions specific to your operation and local conditions.


 RATINGS: 9 = Outstanding; 1 = Poor.

Hybrid and variety responses are variable and subject to any number of environmental, disease and pest pressures. Individual results may vary.

The foregoing is provided for informational use only. Please contact your Pioneer sales professional for information and management suggestions specific to your operation.