2015 Corn Hybrid Demonstration Program Results
Coordinator: Dr. Erick Larson
Extension Associate: Jenny Bibb
Supervisors: Preston Aust, Andy Braswell, Jimbo Burkhalter, Jon Carson, Alex Deason, Dr. Ernie Flint, Judd Gentry, Dan Haire, Reid Nevins, Dr. Dennis Reginelli, Dr. Mark Shankle, Dr. Randy Smith, Lester Stephens, and Charlie Stokes
Cooperators: Brian Barham, Ernest Bledsoe, Pierce Brown, Mallory Chism, Cole’s Creek Planting Co., Danny Donald, Travis Dunn, Albin Flautt, Tommy Garrett, Lee Howell, Scott Hunter, Thornton Marley, Don Mitchell, Tony Morgan, Danny Murphy, Pilkinton-Dantzler Farms, Dustin Roberts, Rodgers’ Farms and David Taylor.
Program Summary: The Corn Hybrid Demonstration Program is intended to provide corn growers, crop consultants, and other ag professionals firsthand opportunity to observe performance of elite hybrids and generate information to better assess hybrid performance and adaptability in Mississippi. This program provides a unique opportunity to observe and evaluate plant characteristics and environmental responses of our best corn hybrids in local, on-farm demonstration plots representing Mississippi’s production systems.
Hybrids selected for this program must be validated by producing superior grain yield in the Mississippi Corn for Grain Hybrid Trials (MAFES IB480) or be relevant market standards. Hybrids are selected annually and grouped into two distinct sets based on performance in dryland or irrigated culture, since these cropping systems are both prevalent and significantly affect corn hybrid adaptability in Mississippi. Seed companies are granted the discretion to enter the hybrid that has demonstrated superior performance in the Mississippi Corn for Grain Hybrid Trials, or a newly released hybrid that they feel is more promising or better adapted. This establishes a very elite group of corn hybrids for evaluation in the program. Each standardized set of hybrids is grown at numerous field locations representing Mississippi cropping systems. Mississippi State University Extension Service regional agronomic crop specialists and county agricultural agents coordinate locations with grower-cooperators and supervise plots during the season.
Hybrid characteristics are rated relative to other entries within the respective set of hybrids (irrigated or dryland) grown at various locations. Thus, these relative rankings are not intended to compare to other or all commercial hybrids available in the market.
Grain Yield Data: Hybrids evaluated in this program are generally planted in “strip trials.” Yield data generated from a single location are not as reliable as when treatments are replicated numerous times. Treatment replication reduces the effect of numerous factors that can impart variability, which may affect performance and confound results. Thus, average yields are calculated from data collected at multiple locations and presented in this publication to better assess yield performance related to hybrid genetics. Analyses of yield data were performed with SAS using GLM procedures, and means are separated at the 0.05 level. This information derived from numerous diverse environments, cropping systems, and soils and is intended to supplement data generated in university hybrid trials.
Technology Traits: All hybrid entries are glyphosate tolerant. Inclusion of other traits is optional and is primarily based on product availability and the discretion of the respective seed companies. Corn borer protection normally enhances yield at locations where corn borers (Southwestern corn borer and/or European corn borer) are present. Rootworm protection is not generally beneficial in our region, as the native Southern corn rootworm species feeds on alternative hosts and primarily damages corn only during seedling establishment. All seed are commercially treated with an insecticide seed treatment, which is at the discretion of each respective seed company. Seed treatments are used to minimize damage from insect pests, including Southern corn rootworms, during seedling establishment.
Relative Maturity: Maturity is measured and reported as the number of days to tassel, as well as relative number of days to physiological maturity (black layer or about 30 percent grain moisture), and does not include additional time for the crop to dry to a desirable harvest moisture.
Plant Height: Plant height is reported as full plant height after tassel emergence. Plant height is one of several factors that may affect light interception, which is critical to optimum corn grain production. Light interception is determined by the leaf canopy, which is influenced by leaf number, leaf size, leaf orientation, row width/pattern, and plant population. Short plant height may reduce potential light interception, particularly in wide rows. Tall plants are generally more likely to lodge and will likely have higher water demand during the growing season.
Ear Height: Ear height is a relative rating of ear height relative to plant height for each specific hybrid in the program. High ear placement may promote more efficient energy use in the plant, as leaves in the upper canopy intercept more light and produce more photosynthetic energy for the developing ear. However, high ear placement may promote lodging because plants are more top-heavy and thus more prone to lodge when exposed to strong wind.
Stalk Strength: Stalk strength is a hybrid’s ability to resist stalk lodging, which occurs when the lower stalk bends, collapses, or breaks above ground level. Stalk lodging often increases when harvest is delayed by inclement weather, which promotes stalk deterioration. Stalk lodging is often more prevalent than root lodging (when the entire stalk severely leans or completely falls from ground level) but is generally less troublesome because timely harvest can mediate potential issues and combines usually can still gather stalks.
Stalk Integrity: Stalk integrity is a characterization of the plant’s ability to maintain integrity after physiological maturity. Late-season stress and adverse weather often promote plant deterioration during the time between physiological maturity and harvest. Poor stalk integrity may appear as shriveled, shredded, or dislodged leaves, and brittle or broken stalks, particularly above the ear.
Disease Resistance: Disease resistance is the hybrid’s ability to resist infection of a specific pathogen. Southern rust was present during the 2015 season at levels substantial enough to evaluate hybrid differences. Ratings are represented in a scale from resistant to very susceptible based on increasing degree of disease infection.
Yield Components: Corn grain yield is determined by the total number of kernels produced and kernel weight. Kernel number is determined by the number of kernel rows an ear produces and the number of kernels per row. These two traits are determined during different growing stages. Kernel row number is determined during late vegetative stages and is the first yield component determined by the plant. Although potential ovule number also develops during late vegetative stages, kernel number is primarily determined during the first few weeks after pollination as young kernels develop up until the milk stage. Successful kernel development is extremely dependent upon high photosynthetic energy production during this specific period and lack of stress. Kernel weight is the final yield component determined. Kernel weight is dependent upon favorable conditions during the latter reproductive stages (dough and dent stages) until physiological maturity.
Test Weight: Test weight is a measurement of grain bulk density and an indicator of general grain quality. It is a standard component used to assess official grain grade for commercial trade.
Publication 3042 (POD-02-17)By Dr. Erick Larson, Associate Extension/Research Professor, Plant & Soil Sciences.