xt74xg9f6081 https://exploreuk.uky.edu/dips/xt74xg9f6081/data/mets.xml   Kentucky Agricultural Experiment Station. 1960 journals 099 English Lexington : Agricultural Experiment Station, University of Kentucky Contact the Special Collections Research Center for information regarding rights and use of this collection. Kentucky Agricultural Experiment Station Progress report (Kentucky Agricultural Experiment Station) n.99 text Progress report (Kentucky Agricultural Experiment Station) n.99 1960 2014 true xt74xg9f6081 section xt74xg9f6081  esults of the
entucky Hybrid Corn
I  erformunce Test -1960 »
4  F. A. LOEFFEL cnd J. F. SHANE
PROGRESS REPORT 99
(Filing Code; 1-1)
g UNIVERSITY OF KENTUCKY
AGRICULTURAL EXPERIMENT STATION
I LEXINGTON

 TESTING LOCATIONS OF ·
THE KENTUCKY HYBRID conn PERFORMANCE TEST
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Area Location Cooperator
Western l. Wickliffe James Wilson
2. Owensboro Beverly Gregory
3. Hopkinsville Murray Wall
Eastern 4. Campbellsville James Noe
5. Lexington Ky. Agr. Exp. Sta.
6. Quicksand Robinson Agr. Exp. Substation
Charles M. Derrickson
4
Acknowledgment is made to Dr. John Hamlin, Director of the
University of Kentucky Computing Center, for assistance in
summarizing the results reported in this progress report.

 RESULTS OF THE KENTUCKY HYBRID CORN
PERFORMANCE TEST IN 1960
F. A. Loeffel and J. F. Shane
The objective of the Kentucky Hybrid Corn
Performance Test is to provide an unbiased estimate
l of the relative performance of corn hybrids being
sold in Kentucky. This information may then be
used by farmers, seedsmen and research and extension
personnel in determining which hybrid most nearly
possesses the characteristics which are desired or
required for a specific situation. The need for
the University of Kentucky Agricultural Experiment
Station to obtain this information is indicated by
the continuing shift to hybrids by the farmers of
Kentucky. Over 97 percent of the Kentucky corn -
acreage was planted to hybrids in 1960.
Although some areas of the state were affected
to some extent by drought, the reports on production
indicate that Kentucky farmers have produced another
exceptionally good crop. Total production was down
almost 3 million bushels. This crop was produced
on 1.7 million acres compared to 1.8 million acres
in 1959. The 1960 state average was 49 bushels and
equals the 49 bushels per acre produced in 1958.
An average state yield exceeding 41 bushels has been
produced for the sixth consecutive year.
Cold, snowy March weather and a late spring
hindered the progress of farm work in 1960. About
two percent of the state's corn crop was in the
ground by April 26 compared to seven percent in 1959.
Soil moisture was generally adequate in the western
third of the state, but shortages were general in
the eastern two-thirds. By May 17 about 40 percent
(3)

 of the corn acreage was planted compared to 70 per-
cent in 1959 and 25 percent in 1958. Corn in the
early planted fields yellowed due to the continued
cool weather. Planting was about 95 percent complete
by the middle of June.
Frequent heavy rains in late June and early
July caused severe crop damage in many areas of
the state. Creek bottoms and low "pocket" cropland
suffered the heaviest damage. Surplus soil moisture
was reported by 90 percent of the crop observers.
Approximately 40 percent of the corn crop had been
harvested by the middle of October.
Kentucky average rainfall for the growing
season, April through September, totaled 22.41
inches which is 0.50 inches below normal and 1.14
inches above 1959. July and August were about 15
percent below normal in rainfall while September
had a little more than average rainfall.
Northern and southern corn leaf blight were
more prevalent in the tests in 1960 than they were
in 1959. Stewart's corn leaf blight was not as
prevalent as in 1959.
The average yield for all hybrids grown at
six locations in 1960 was 108.1 bushels. The
highest test average was 126.8 bushels grown at
Lexington. The lowest test average was 101.1
bushels for the Wickliffe test.
EXPERIMENTAL METHODS
The performance test was conducted at six
locations which represent corn—producing areas
typical of the state. These locations together
(4)

 with the name of the cooperator are listed on the
inside of the front cover. These testing sites
were grouped by geographical location into a
western and eastern area for convenience in present-
“ing the results. Yields from Wickliffe, Owensboro,
.and Hopkinsville were averaged for the western area.
Similarly the yields from Campbellsville, Lexington,
· and Quicksand were averaged for the eastern Kentucky
area.
Forty-seven hybrids which are available to the
pfarmers of Kentucky through commercial trade channels
were compared. These hybrids, developed by state
and federal research agencies and by private seed
companies, are listed in Table l. Information
concerning the seed source of the hybrid, the kernel
color and the type of cross are presented. The
type of hybrid is desiganted as follows: double
cross, 4X; three—way crosses, 3X; and a single cross
as 2X. Seed of a single cross hybrid sells at a
premium due to increased costs of producing seed.
Forty-five double crosses, one three-way cross and
one single cross, were evaluated this year.
The pedigrees of hybrids developed by state and
federal agencies are listed in Table 2. Agronomic
information pertaining to the testing locations is
presented in Table 3. Results of the Kentucky
Hybrid Corn Performance Test are sum arized for
periods of 3 years, 2 years and l year and are
presented in Tables 4-6 respectively. The hybrids
are grouped in the tables on the basis of kernel
color. Within groups the hybrids are listed in
order of increasing moisture content. The reaction
of the hybrids to Northern, Southern, and Stewarts
leaf blight are sum arized in Table 7. The hybrids
in Table 7 are listed in alphabetical order.
(5)

 Field Design.
Each hybrid was planted in 4 plots at each of
the 6 locations with individual plots being 2 hills
wide and 5 hills long. These plots were located in
different parts of the testing field to minimize
cultural and soil differences. All tests were `
planted at the rate of 6 kernels per hill and the .
resulting plants thinned to 4 per hill.
Yield.
The corn from each plot was harvested and
weighed individually. The yield of the hybrids
was determined and is reported on the basis of
bushels of shelled corn per acre with a moisture
content of l5.5 percent. Adjustments were made
for missing hills but not for other variation in
stand. Therefore, the yields at each location
reported in this progress report constitute an
average yield of the 4 plots after all adjustments
were made.
Moisture.
The moisture content at harvest is the best
measure of relative maturity of hybrids which is
available. A hybrid may be considered to be ear-
lier than a second hybrid if its moisture content
at harvest is consistently lower. Maturity thus
determined is not absolute but is relative to the
hybrids being compared.
Two moisture samples were taken for each
hybrid by taking a sample from replication l and 2,
and from replication 3 and 4. The moisture content
in the grain was determined at harvest by removing
2 rows of kernels from each of lO ears selected
at random from each of two replications. The grain
from the 20 ears was thoroughly mixed and the
moisture content of a lOO-gram sample was determined
with a Steinlite moisture meter.
(6)

 Erect Plants.
The percent erect plants is considered to be
an estimate of the resistance of a hybrid to the
total insect and disease complex affecting standing
ability. This value is obtained by counting plants
with stalks broken between the ear bearing node and
ground level and those which lean from the base at
an angle of more than 30 degrees from the vertical.
This sum is subtracted from the plants present and
P the difference divided by the total plants present
to give the percent erect plants.
Ear Height.
Ear height, distance from the base of the
plant to the point of attachment of the upper ear,
was measured visually using a scale with one-foot
intervals. Visual ratings were taken on four plots
of each hybrid at each location.
Disease.
Visual ratings of hybrid reaction to Northern,
Southern, and Stewarts leaf blight diseases are
recorded at each location when sufficient natural
infection is present. A five-class rating scale
is used.
INTERPRETATION
The performance of hybrids vary with weather
conditions which change from season to season and
from testing location to testing location in the
same season. Since the weather conditions cannot
be predicted at the time of planting, a farmer should
plant a hybrid which has a good performance in an
"average" season. The best estimate of hybrid per-
formance for an “average" season is obtained by
combining the results obtained from a large number
of experiments grown in different years at a number
of locations.
(7)

 The information presented in Table 4 is the
average of 17 individual experiments grown in 1958,
1959, and 1960. In Table 5 are summarized the
results obtained from 12 experiments grown in 1959
and 1960. Table 6 contains information obtained
from 6 experiments grown in 1960 at different
locations in the state. For this reason, the
information contained in Table 4 is the best estimate
available for comparing the performance of corn
hybrids for average growing conditions in Kentucky.
BE YOUR OWN JUDGE
Improvements in corn hybrids are constantly
being made. An efficient corn producer will want
to keep informed on these improvements and to
determine if they will produce on his farm. For
this reason, it is suggested that new hybrids be
grown frequently on a trial basis in comparison
with the hybrid or hybrids presently grown. A
farmer often changes his entire corn acreage to a
different hybrid. He then compares his old hybrid
grown the previous year with the new hybrid grown
the current year. Since the two hybrids were grown
under different weather conditions, this comparison
is not valid and often leads to incorrect decisions.
Hybrids being compared should be grown in the same
field using identical management practices. A
good way to do this is to plant one—half bushel or
one bushel of seed of the new hybrid in the center
of a field being sure to mark it at planting time.
At harvest, yield should be determined and other
observational notes recorded. It is important to
observe the hybrids frequently during the growing
season as well. If this suggestion is followed,
a corn grower will be able to select hybrids which
most nearly fits his conditions.
(8)

 Strip tests can also be used by individual
lfarmers to determine the value of other factors
contributing to production efficiency. It is
important for a farmer to have an unfertilized
check strip, and a strip receiving twice the
quantity of fertilizer that the remainder of the
field received. This enables him to determine if
his investment in fertilizer was profitable and
. whether he used too little or too much fertilizer.
The number of corn plants per acre in Kentucky is
generally too low for top production. It would be
well worth the time and effort to change the setting
on the drill and compare yields at different rates of
planting. It should be kept in mind, however, that
plant population and fertility level must be kept in
balance for efficient production.
D0 YOUR PART TO CONTRIBUTE TOWARD
A 50 BUSHEL AVERAGE CORN YIELD IN
KENTUCKY IN l96l
(9)

 Table 1. Hybrids tested in 1960.
 
Hybrid Color Cross Source of Hybrids
 
AES 705 Y ax Agricultural Experiment
805 Y ax Station (North Central)
809 Y ax
Broadbent A02B Y ax Broadbent Hybrids
Cobb, Kentucky
Cardinal 107 Y ax George Street
Henderson, Kentucky
Crib Filler 116 Y ax Mitchell Farms
123 Y ax Windfall, Indiana
131 Y ax
138 Y ax
Dekalb 633 Y ax Dekalb Agricultural
803 Y 3X Ass'n., Dekalb,
805 Y 2X Illinois
837 Y ax
852 Y ax
869 Y ax
925 W ax
1028 Y ax
Funk G—96 Y ax Columbia Seed
G—l44 Y ax Company, Eldred,
G—509W W ax Illinois
G-71lAA Y ax
Hagan H-2 Y ax R. M. Hagan
H-9 Y ax Owensboro, Kentucky
Ken-Bred E-20Y Y ax Ken-Bred Producers
Patmor, Jackson, Thompso
Marion, Danville,
Hillsboro, Kentucky
(IO)

 Table l. Continued.
 
Hybrid Color Cross Source of Hybrids
 
Ky l05 Y ax University of Kentucky
l06A Y ax Agricultural Experiment
‘ 204 W ax Station, Lexington
205W W ax
Meacham M-5 W ax Meacham's Koreandale
M—33Y Y 4X Farms, Morganfield,
Kentucky
P.A.G. 434 Y ax Pfister Associated
633W W 4X Growers, Inc., Aurora,
Illinois and Huntsville,
Alabama
Pioneer 300H Y ax Pioneer Corn Company
309A Y ax Tipton, Indiana
309B Y ax
3l2A Y ax
319 Y ax
Stull l00Y Y ax Stull Brothers, Inc.
100YA Y ax Sebree, Kentucky
l0lY Y ax
10lYA Y ax
lOlYAA Y ax
108Y Y Ax
400WC W ax
500W W ax
US 13 Y ax Experiment Station
523W W ax (U.S.D.A.)
(11)

 Tab1e 2. Pedigrees of Experiment Station and
U. S. hybrids tested in 1960.
Hybrid Pedigree
AES 705 (WF9 x B14)(C103 x Oh 43)
AES 805 (wF9 x 38—1l)(C103 x Oh 45)
AES 809 (WF9 x P8)(Oh 43 x C103)
Ky 105 (T8 x CI21E)(38—11 x Oh 7B)
Ky 106A (WF9 x 38-11)(CI21E x Oh 41)
Ky 204 (K64 x 33-16)(K55 x Ky 201)
Ky 205W (Ky 211 x 33—16)(Ky 209 x H21)
US 13 (WF9 x 38-11)(Hy x L317)
US 523W (K55 x K64)(Ky 27 x Ky 49)
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(21)

 --— N O T E S —-— V
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 --- N O T E S ---
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 HYBRID, DATE AND RATE OF PLANTING STUDIES OF CORN
Six hybrids, representative of three maturity groups
were planted at three different rates at four dates in
replicated trials conducted at several location in
Kentucky in 1957, 1959, and 1960. Yield data obtained
from these trials are summarized in the following table:
‘ Rate of
Planting Date of Planting Yiel-
Plants/Acre A·ril 25 Ma 12 Ma 25 June 8 bu./(
8,000 74.5 72.9 66.0 60.1 68. V
12,000 88.1 87.9 78.6 75.1 82.*
16,000 94.6 90.7 81.0 74.3 85.1
Yield
bu./A 85.7 83.8 75.2 69.8
The yield of corn decreases as planting is delayed
after April 25. The rate of decrease is small until the
middle of May but becomes greater as planting is delayed.
Considerable thought should be given before replanting
since delayed plantings will yield less on the average.
The average corn plant population at harvest in
Kentucky is estimated to be 8,000 plants per acre. The
trials indicate that low plant population seriously limit
production. Yields were increased 14 bushels by increasi
the plant population to 12,000 plants per acre. Increasi
plant number to 16,000 plants per acre further increased
yields. These results were obtained on fields of medium
fertility. However, more fertilizer should be applied
to the heavier plant populations for most efficient
production, especially when the fertility of the field
is known to be low.
10M-1-61