December 2009
A3653
2009 WISCONSIN CORN HYBRID PERFORMANCE TRIALS
GRAIN AND SILAGE
Joe Lauer, Kent Kohn, and Thierno Diallo
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The University of Wisconsin Extension-Madison and College of Agricultural and Life
Sciences conduct a corn evaluation program, in cooperation with the Wisconsin Crop
Improvement Association. The purpose of this program is to provide unbiased performance
comparisons of hybrid seed corn available in Wisconsin . These trials evaluate corn
hybrids for both grain and silage production performance.
In 2009, grain and silage performance trials were planted at fourteen locations
in four production zones. Both seed companies and university researchers submitted
hybrids. Companies with hybrids included in the 2009 trials are listed in
Table 1. Specific hybrids and where they were tested are shown in
Table 2. In the back of the report, hybrids previously tested over the
past three years are listed (Table 24). At most locations
trials were divided into early and late maturity trials, based on the hybrid Relative
Maturities provided by the companies. The specific Relative Maturities separating
early and late trials are listed below.
GROWING CONDITIONS FOR 2009
Seasonal precipitation and temperature at the trial sites are shown in
Table 4. Spring planting was delayed due to cool and wet planting conditions.
Over the entire growing season precipitation was average, but growing degree days
were significantly less than normal. In many areas of the state, it was one of the
coolest growing seasons ever recorded. Plant stands in the trials were excellent.
Drought was experienced during June and July in northern Wisconsin. Little insect
or disease pressure was observed in most trials. Due to the cool growing season,
plants stayed green late into the harvest season, so standability was excellent,
Beautiful weather in early September and an average killing frost date helped the
crop mature. Wet conditions during October caused molds to develop. Harvest grain
moisture was higher than normal in all trials. Yields in the UW hybrid trials were
average to above average at most sites.
CULTURAL PRACTICES
The seedbed at each location was prepared by either conventional or conservation
tillage methods. Seed treatments of hybrids entered into the trials are described
in Table 3. Fertilizer was applied as recommended by
soil tests. Herbicides were applied for weed control and supplemented with cultivation
when necessary. Corn rootworm insecticide was applied when the previous crop was
corn. Information for each location is summarized in Table 5.
PLANTING
A precision vacuum corn planter was used at all locations, except Spooner. Two-row
plots, twenty-five foot long, were planted at all locations. Plot were not hand-thinned.
Each hybrid was grown in at least three separate plots (replicates) at each location
to account for field variability.
HARVESTING
Grain: Two-row plots were harvested with a self-propelled corn combine. Lodged
plants and/or broken stalks were counted, plot grain weights and moisture contents
were measured and yields were calculated and adjusted to 15.5% moisture. Test weight
was measured on each plot.
Silage: Whole-plant (silage) plots were harvested using a tractor driven,
three-point mounted one-row chopper. One row was analyzed for whole plant yield
and quality. Plot weight and moisture content were measured, and yields were adjusted
to tons dry matter / acre. A sub-sample was collected and analyzed using near infra-red
spectroscopy.
Wisconsin Relative Maturity Belts and test sites.
|
Grain
|
Southern Zone
Arlington, Janesville, Lancaster
|
Early Maturity Trial: 105‑day or earlier
Late Maturity Trial: later than 105‑day
|
Table 6
Table 7
|
South Central Zone
Fond du Lac, Galesville, Hancock (irrigated)
|
Early Maturity Trial: 100‑day or earlier
Late Maturity Trial: later than 100‑day
|
Table 8
Table 9
|
North Central Zone
Chippewa Falls, Marshfield, Seymour, Valders
|
Early Maturity Trial: 90‑day or earlier
Late Maturity Trial: later than 90‑day
|
Table 10
Table 11
|
Northern Zone
Spooner (three sites), Coleman
|
|
Table 12
|
|
Silage
|
Southern Zone
Arlington and Lancaster
|
Early Maturity Trial: 109‑day or earlier
Late Maturity Trial: later than 110‑day
|
Table 13
Table 14
Graph
|
South Central Zone
Fond du Lac and Galesville
|
Early Maturity Trial: 104-day or earlier
Late Maturity Trial: later than 104-day
|
Table 15
Table 16
Graph
|
North Central Zone
Chippewa Falls, Marshfield, Valders
|
Early Maturity Trial: 99‑day or earlier
Late Maturity Trial: later than 99‑day
|
Table 17
Table 18
Graph
|
Northern Zone
Spooner (two sites), Coleman
|
|
Table 19
Graph
|
|
Specialty Trials
|
Conventional (Refuge)
Arlington, Janesville, Lancaster
|
|
Table 20
|
Organic
Arlington, Janesville, Lancaster
Fond du Lac, Galesville, Hancock
Chippewa Falls, Marshfield, Seymour, Valders
|
Southern Zone
South Central Zone
North Central Zone
|
Table 21
Table 22
Table 23
|
PRESENTATION OF DATA
Yield results for individual location trials and for multi-location averages are
listed in Tables 6 through 23. Within each trial, hybrids are ranked by moisture,
averaged over all trials conducted in that zone during 2009. Yield data for both
2008 and 2009 are provided if the hybrid was entered previously in the 2008 trials.
A two-year average for yield is calculated using location means as replications.
New in 2009, was a nearest neighbor analysis of variance for all trials as described
by Yang et al. (2004, Crop Science 44:49-55) and Smith and Casler (2004, Crop Science
44:56-62). A hybrid index (Table 2) lists relative
maturity ratings, specialty traits, seed treatments and production zones tested
for each hybrid.
RELATIVE MATURITY
Seed companies use different methods and standards to classify or rate the maturity
of corn hybrids. To provide corn producers a "standard" maturity comparison
for the hybrids evaluated, the average grain or silage moisture of all hybrids rated
by the company relative maturity rating system are shown in each table as shaded
rows. In these Wisconsin results tables, hybrids with lower moisture than
a particular relative maturity average are likely to be earlier than that
relative maturity, while those with higher grain moisture are most likely
later in relative maturity. Company relative maturity ratings are rounded
to 5-day increments.
The Wisconsin Relative Maturity rating system for grain and silage (GRM and SRM)
compares harvest moisture of a grain or silage hybrid to the average moisture of
company ratings using linear regression. Each hybrid is rated within the trial and
averaged over all trials in a zone. Maturity ratings (Company, GRM and SRM) can
be found in Table 2.
GRAIN PERFORMANCE INDEX
Three factors-yield, moisture, and standability-are of primary importance in evaluating
and selecting corn hybrids. A performance index (P.I.), which combines these
factors in one number, was calculated for multi‑location averages for grain trials.
This performance index evaluates yield, moisture, and lodged stalks at a 50 (yield):
35 (moisture): 15 (lodged stalks) ratio.
The performance index was computed by converting the yield, dry matter, and upright
stalk values of each hybrid to a percentage of the test average. Then the performance
index for each hybrid that appears in the tables was calculated as follows:
Performance Index (P.I.) = [(Yield x 0.50) + (Dry matter x 0.35) + (Upright
stalks x 0.15)] / 100
SILAGE PERFORMANCE INDEX
Corn silage quality was analyzed using near infra-red spectroscopy equations derived
from previous work. Plot samples were dried, ground, and analyzed for crude protein
(CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), in vitro cell wall
digestibility (NDFD), in vitro digestibility (IVD), and starch. Spectral groups
and outliers were checked using wet chemistry analysis.
The MILK2006 silage performance indices, milk per ton and milk per acre,
were calculated using an adaptation by Randy Shaver (UW-Madison Dairy Science Department)
of the MILK91 model (Undersander, Howard and Shaver; Journal Production Agriculture
6:231-235). In MILK2006, the energy content of corn silage was estimated using a
modification of a published summative energy equation (Weiss and co-workers, 1992;
Animal Feed Science Technology 39:95-110). In the modified summative equation,
CP, fat, NDF, starch, and sugar plus organic acid fractions were included along
with their corresponding total-tract digestibility coefficients for estimating the
energy content of corn silage. Whole-plant dry matter content was normalized to
35% for all hybrids. The sample lab measure of NDFD was used for the NDF digestibility
coefficient. Digestibility coefficients used for the CP, fat, and sugar plus organic
acid fractions were constants. Dry matter intake was estimated using NDF and NDFD
content assuming a 1350 lb. cow consuming a 30% NDF diet. Using National Research
Council (NRC, 2001) energy requirements, the intake of energy from corn silage was
converted to expected milk per ton. Milk per acre was calculated using
milk per ton and dry matter yield per acre estimates.
LEAST SIGNIFICANT DIFFERENCE
Variations in yield and other characteristics occur because of variations in soil
and growing conditions that lower the precision of the results. Statistical analysis
makes it possible to determine, with known probabilities of error, whether a difference
is real or whether it might have occurred by chance. Use the appropriate LSD (least
significant difference) value at the bottom of the tables to determine true differences.
Least significant differences (LSD's) at the 10% level of probability are shown.
Where the difference between two selected hybrids within a column is equal to or
greater than the LSD value at the bottom of the column, you can be sure in nine
out of ten chances that there is a real difference between the two hybrid averages.
If the difference is less than the LSD value, the difference may still be real,
but the experiment has produced no evidence of real differences. Hybrids that were
not significantly lower in performance than the highest hybrid in a particular test
are indicated with an asterisk (*).
HOW TO USE THESE RESULTS TO SELECT TOP-PERFORMING HYBRIDS
The results can be used to provide producers with an independent, objective evaluation
of performance of unfamiliar hybrids, promoted by seed company sales representatives,
compared to competitive hybrids.
Below are suggested steps to follow for selecting top-performing hybrids for next
year using these trial results:
- Use multi-location average data in shaded areas. Consider single location
results with extreme caution.
- Begin with trials in the zone(s) nearest you.
- Compare hybrids with similar maturities within a trial. You will need to divide
most trials into at least two and sometimes three groups with similar average harvest
moisture-within about 2% range in moisture.
- Make a list of 5 to 10 hybrids with highest 2009 Performance Index within each maturity
group within a trial.
- Evaluate consistency of performance of the hybrids on your list over years
and other zones.
- Scan 2008 results. Be wary of any hybrids on your list that had a 2008 Performance
Index of 100 or lower. Choose two or three of the remaining hybrids that have relatively
high Performance Indexes for both 2008 and 2009.
- Check to see if the hybrids you have chosen were entered in other zones.
(For example, some hybrids entered in the Southern Zone Trials, Tables 6 and 7,
are also entered in the South Central Zone Trials, Tables 8 and 9).
- Be wary of any hybrids with a Performance Index of 100 or lower for 2008
or 2009 in any other zones.
- Repeat this procedure with about three maturity groups to select top-performing
hybrids with a range in maturity, to spread weather risks and harvest time.
- Observe relative performance of the hybrids you have chosen based on these trial
results in several other reliable, unbiased trials and be wary of
any with inconsistent performance.
- You might consider including the hybrids you have chosen in your own test plot,
primarily to evaluate the way hybrids stand after maturity, dry-down rate, grain
quality, or ease of combine-shelling or picking.
- Remember that you don't know what weather conditions (rainfall, temperature)
will be like next year. Therefore, the most reliable way to choose hybrids with
greatest chance to perform best next year on your farm is to consider performance
in 2008 and 2009 over a wide range of locations and climatic conditions.
You are taking a tremendous gamble if you make hybrid selection decisions based on
2009 yield comparisons in only one or two local test plots.
OBTAINING DATA ELECTRONICALLY
This report is available on the internet at
http://corn.agronomy.wisc.edu. Hybrid performance for the last 10 years
can be summarized using SELECT at the above internet address. This book can be downloaded
over the internet in Microsoft Excel and
Acrobat PDF formats.
About the authors: Joe Lauer is a professor of agronomy and also holds an
appointment with University of Wisconsin-Extension. Kent Kohn is the corn program
manager in agronomy and Thierno Diallo is an assistant research specialist in agronomy.
This publication is available from your Wisconsin County Extension office or from
the Department of Agronomy, 1575 Linden Drive, Madison, WI 53706 . Phone (608) 262-1390.
University of Wisconsin-Extension, Cooperative Extension, in cooperation with the
U.S. Department of Agriculture and Wisconsin counties, publishes this information
to further the purpose of the May 8 and June 30, 1914 Acts of Congress; and provides
equal opportunities and affirmative action in employment and programming.
References to transgenic traits in this publication are for your convenience
and are not an endorsement or criticism of one trait over other similar traits.
Every attempt was made to ensure accuracy of traits in the hybrids tested. You are
responsible for using traits according to the current label directions of seed companies.
Follow directions exactly to protect the environment and people from misuse. Failure
to do so violates the law.
If you need this material in an alternative format, contact Cooperative Extension
Publications at (608) 262-2655 or the UWEX Affirmative Action office. This publication
is available free from your Wisconsin county Extension office or from the Department
of Agronomy, 1575 Linden Dr., Madison, Wisconsin 53706. Phone (608) 262-1390
A3653 2009 Wisconsin Hybrid Corn Performance Trials - Grain and Silage.