Michigan Corn Grain Trials
Introduction
Michigan State University’s Department of Crop and Soil Sciences conducts hybrid corn silage trials each year in cooperation with MSU Extension, seed corn companies, and farmers.
Seed companies are invited to enter hybrids in the trials. A fee is charged to cover expenses.
Company names used in association with hybrid designations refer to the hybrid. In the index, numbers in parentheses following the hybrid refer to the table(s) or zone(s) in which each hybrid appears.
Methods
Three trial locations were planted in each of four maturity zones (see trial map). Two trial locations were utilized in Zone 5 at Alger and Delta Counties. Maturity zones are based on the average number of growing degree units available during the growing season as reported in long-term weather records. Hybrids entered in a zone were tested in each trial location within that zone. Entries for zones 1, 2 and 3 are divided into two-maturity groups (early and late) based on maturity ratings provided by the seed companies. In zones 4 and 5 the hybrids are tested as one maturity group only. Experimental design, data acquisition, analysis of variance, and data summarization were facilitated by AGROBASE Generation I I™(Agronomix Software, Inc., Winnipeg, Canada). The experimental design is a lattice design with four replications. Hybrid performance is reported as the adjusted mean of four plots.
Variety trials were conducted in farmer’s fields. All hybrids in a location were treated with the same management practices, e.g., fertilizers, seeding rate, date of planting, weed control, etc. Four-row plots were used at all locations. The two center rows were harvested for yield. Plots were 22-feet long with 30-inch row spacing. In the field, hybrids were identified only by plot number to assure unbiased comparisons. Both early and late grain trials in Branch, Cass, Mason, and Montcalm Counties were irrigated.
Stand counts were conducted in June. Plots with stand counts higher than the desired population were thinned at this time. The desired population rates are listed in the Silage Agronomic Table. Lodging measurements were made at harvest, counting all plants broken below the ear and/or leaning more than 45 degrees. Plots were harvested mechanically. Moisture content and field weight were measured by a GrainGage™, a HarvestMaster System™ (Juniper Systems, Inc., Logan, UT) mounted on the plot combine. Grain yield is reported at standard 15.5 percent moisture. Grain test weight is reported at harvest moisture. Automated test weight equipment loses some accuracy as harvest moistures increase. Test weight values should be used to determine relative rank and not as a precise weight.
The results shown are the average of four replications grown in close proximity to each other. Two or more plots of the same hybrid in the same field may produce somewhat different results because of uncontrolled variability in the soil and other environmental factors. Replication and randomization of the entries are two methods used to account for this variation. Because these methods do not eliminate all variables, the magnitude of difference necessary for statistical significance has been calculated for yield, moisture content, and test weight. The value calculated as the “least significant difference” or “LSD” is the amount that an individual hybrid would have to differ from another hybrid in the same test to be considered statistically significantly different from that hybrid. The CV, or coefficient of variation, is indicative of a trial’s precision. Trials with low levels of error variation have lower CV values.
The tables report the following information about the hybrids tested:
- Moisture content at harvest (%H20).
- Yield (in bushels per acre) of shelled corn at 15.5 percent moisture (Bu/A).
- Test weight at harvest moisture (Twt).
- Percent of stalk lodging (plants broken below the ear and/or 45o off vertical at harvest) (%SL).
- Percent stand of target population (%Std).
Grain Quality
Grain quality data was determined using Near Infrared Spectral (NIR) analysis on replicated whole grain samples from one location in each zone. NIR analysis involves irradiating the sample with light in the near infrared range (1100 to 2500 nm). The illuminated sample absorbs light energy proportionally to specific chemical and physical properties. The reflected energy is measured and correlated statistically with established forage quality levels. Results for protein, starch, and oil content are presented in each table.
Percent protein (Prot), oil (Oil), and starch (Strch) content are reported
at 15.5 percent grain moisture.
Corn Grain