THE UNIVERSITY OF ILLINOIS commercial soybean testing program was started in 1969 as a result of requests by seedsmen that their private varieties be tested. There were 96 conventional and 544 roundup resistant varieties from 60 seed companies tested in 2002.
The purpose of this commercial soybean testing program is to provide unbiased, objective, and accurate testing of all varieties entered. The tests are conducted on as uniform a soil as is available in the testing area. Small plots are used to reduce the chance of soil and climatic variations occurring between one variety plot and another.
The results of these tests should help you judge the merits of varieties in comparison with other private and public varieties. Because your soils and management may differ from those of the test location, you may wish to plant variety strips of the higher-performing varieties on your farm. The results printed in this circular should help you decide which varieties to try.

TEST PROGRAM

Selection of entries. Seed companies in Illinois and surrounding states were invited to enter soybean varieties, brands, or blends in the 2002 Illinois soybean performance trials. Entrants were required to enter all nonirrigated, 30-inch-row-width trials on a regional basis. To finance the testing program, a fee of $80 per location was charged for each variety entered by the seed company. Most of these varieties, brands, or blends are commercially available, but some experimental varieties were also entered. A total of 2,569 entries were tested in 2002.
Number and location of tests. In 2002, tests were conducted at 13 locations in the state (see map). These sites represent the major soils and maturity zones of the state.

Nonirrigated, 30-inch-row-width trials, conventional and roundup resistant, were conducted on a regional basis. The regions are as follows:
Region 1 Erie, Mt. Morris and DeKalb
Region 2 Monmouth, Goodfield and Dwight
Region 3 Perry, New Berlin and Urbana
Region 4 Brownstown and Belleville
Region 5 Carbondale and Dixon Springs
Seven-inch-row-width conventional and roundup resistant trials were conducted at Urbana.

Field plot design. Entries of each test were replicated three times in a randomized complete block or alpha lattice design. The 30-inch-row trial plots consisted of four rows, each 21 feet long. The center two rows of each plot were harvested to measure yield. The 7-inch-row trial plots consisted of eight rows, each 21 feet long. The center six rows were harvested to measure yield.

Fertility and weed control. All test locations were at a high level of fertility. Herbicides were used at all test locations for weed control. Weed control for the roundup resistant trials consisted of post-emergence applications of Roundup as needed, no pre-emergence herbicide was used. Plots were also weeded by hand if needed.

Method of planting and harvesting. The 30-inch-row variety trials were planted with a modified bean planter. A custom-built, cone type, narrow-row drill was used to plant the 7-inch trials. Harvesting was done with a small-plot combine. No allowances were made for beans that may have been lost as a result of combining or shattering.

Soybean Cyst Nematode. Soil samples were taken from variety plots at each location in August and evaluated for cyst populations. Threshold numbers of cysts per 100cc of soil are as follows:

Low 1-5
Medium 6-25
High >25


PERFORMANCE DATA


Yield. Soybean yield was measured in bushels (60 pounds) per acre at a moisture content of 13 percent. An electronic moisture monitor was used on the combine for all moisture readings.

Maturity. Maturity was stated as the date when approximately 95 percent of the pods were ripe.

Lodging. The amount of lodging was rated at harvest time. The following scale was used:


1 - Almost all plants erect
2 - All plants leaning slightly or afew plants down
3 - All plants leaning moderately (45o), or 25 to 50 percent of the plants down
4 - All plants leaning considerably, or 50 to 80 percent of the plants down
5 - Almost all plants down


Height. Height was measured shortly before harvest as the average length of plants from the ground to the tip of the main stem.
Shattering. The percentage of open pods was estimated at harvest time. The following scale was used:


1 - No shattering
2 - 1 to 10% of pods open
3 - 10 to 25% of pods open
4 - 25 to 50% of pods open
5 - Over 50% 0f pods open

Shattering was not significant at any location.

 

SUGGESTIONS FORCOMPARING ENTRIES

It is impossible to obtain an exact measure of performance when conducting any test of plant material. Harvesting efficiency may vary, soils may not be uniform, and many other conditions may produce variability. Results of repeated tests are more reliable than those of a single year or a single-strip test. When one variety consistently out yields another at several test locations and over several years of testing, the chances are good that this difference is real and should be considered in selecting a variety. However, yield is not the only indicator. You should also consider maturity, lodging, plant height and shattering.
As an aid in comparing soybean varieties, brands, and blends within a single trial, certain statistical tests have been devised. One of these tests, the least significant difference (L.S.D.), when used in the manner suggested by Carmer and Swanson1 is quite simple to apply and is more appropriate than most other tests. When two varieties are compared and the difference between them is greater than the tabulated L.S.D. value, the varieties are judged to be "significantly different."
The L.S.D. is a number expressed in bushels per acre and presented following the average yield for each location. An L.S.D. level of 25% is shown. Find the highest yielding soybean variety within the regional table or single location table of interest, subtract the 25% L.S.D. value from the highest yielding variety, every variety with a greater yield than the resulting number is 'statistically the same' as the highest yielding variety. Consider the merits of the varieties in this group when making varietal selections.
In a study of the frequencies of occurrence of three types of statistical errors and their relative seriousness, Carmer2 found strong arguments for an optimal significance level in the range = 0.20 to 0.40, where is the Type I statistical error rate for comparisons between means that are really equal. Herein, a value of = 0.25 is used in computing the L.S.D. 25-percent level shown in the tables.
To make the best use of the information presented in this circular and to avoid any misunderstanding or misrepresentation of it, the reader should consider an additional caution about comparing varieties. Readers who compare varieties in different trials or row spacings should be extremely careful, because no statistical tests are presented for that purpose. Readers should note that the difference between a single varieties performance at one location or row spacing and its performance at another is caused primarily by environmental effects and random variability. Furthermore, the difference between the performance of variety A in one trial or row spacing and the performance of variety B in another trial or row spacing is the result not only of environmental effects and random variability, but of genetic effects as well.

1Carmer, S.G. and M.R. Swanson. "An Evaluation of Ten Pairwise Multiple Comparison Procedures by Monte Carlo Methods." Journal of American Statistical Association 68:66-74. 1973.
2Carmer, S.G. "Optimal Significance Levels for Application of the Least Significant Difference in Crop Performance Trials." Crop Science 16:95-99, 1976.


2002 TEST FIELDS

Erie
Location: Slaymaker farm, Whiteside county, west of Rock Falls, northwestern Illinois.
Soil Type: Beaucoup silty clay loam.
Cooperator: Robert Slaymaker.
Planting Date: May 8.
Harvest Date: October 11.
Herbicide: Pre-Boundary, Post- FirstRate, Select
Roundup trial: Post- Roundup only.
Tillage: fall chisel, spring field cultivate.
S.C.N.: low.

Mt. Morris
Location: Nelson farm, Ogle county, North of Mt. Morris, north central Illinois.
Cooperator: Rick Nelson.
Soil type: Muscatine silt loam.
Planting Date: May 8.
Harvest Date: October 11.
Herbicide: Pre-Boundary, Post-FirstRate, Select.
Roundup Trial: Post- Roundup only.
Tillage: spring chisel & field cultivate.
S.C.N.: low

DeKalb
Location: University of Illinois, Northern Illinois Agronomy Research Center, DeKalb County, southwest of DeKalb.
Soil type: Flanagan silt loam (dark brown, adequately drained, highly fertile).
Cooperators: Lyle Paul, research director; Dave Lindgren, farm foreman.
Planting date: May 7.
Harvest dates: October 12 & 14.
Herbicide: Pre-Boundary, Post-FirstRate, Select.
Roundup trial: Post- Roundup.
Tillage: fall plow, spring mulch finisher (twice).
S.C.N.: low.

Monmouth
Location: University of Illinois, Northwestern Illinois Agricultural Research and Demonstration Center, Warren County, northwest of Monmouth.
Soil type: Muscatine silt loam.
Cooperators: Eric Adee, agronomist; Martin Johnson, farm foreman.
Planting date: May 8.
Harvest dates: October 1 & 9.
Herbicide: Pre- Boundary.
Roundup trial: Post- Roundup only.
Tillage: fall chisel, spring field cultivate.
S.C.N.: low.

Goodfield
Location: Wurmnest farm, Woodford county, north of Goodfield, central Illinois.
Cooperator: Mike Wurmnest.
Soil Type: Ipava silt loam.
Planting date: May 30.
Harvest date: October 10.
Herbicide: Pre-Boundary, Post-FirstRate, Select.
Roundup trial: Post- Roundup only.
Tillage: fall chisel, spring soil finisher (twice).
S.C.N. low.

Dwight
Location: Livingston County, Zabel Farm.
Soil type: Elliott silty clay loam.
Cooperator: Larry Zabel.
Planting date: May 7.
Harvest dates: October 1 & 5.
Herbicide: Pre-Boundary, Post-FirstRate, Select.
Roundup trial : Post- Roundup only.
Tillage: fall chisel, spring field cultivate.
S.C.N.: low.

Perry
Location: Orr Agricultural Research and Demonstration Center, near Perry, Pike County, west central Illinois.
Soil type: Downs silt loam.
Cooperators: Glenn Raines, research director; Mike Vose, farm foreman.
Planting date: May 22.
Harvest dates: September 30 & October 9.
Herbicide: Pre-Boundary, Post-FirstRate, Select.
Roundup trial: Post- Roundup only.
Tillage: fall chisel, spring field cultivate.
S.C.N.: medium.

New Berlin
Location: King farm, Sangamon county, north of New Berlin, Central Illinois.
Cooperator: Ike King.
Soil type: Sable silty-clay loam.
Planting date: May 22.
Harvest date: September 25 & October 8.
Herbicide: Pre-Boundary, Post-FirstRate, Select.
Roundup trial: Post- Roundup only.
Tillage: fall chisel, spring field cultivate.
S.C.N. low.

Urbana
Location: University of Illinois, Crop Sciences Research & Education Center, Champaign County, east central Illinois.
Soil type: Flanagan silt loam (dark brown, adequately drained).
Cooperators: Robert Dunker, farm manager; Mike Kleiss, farm foreman.
Planting dates: May 23.
Harvest dates: September 26, 27, October 6 & 7.
Herbicide: Pre-Boundary, Post-FirstRate, Select.
Roundup trial: Post- Roundup only.
Tillage: fall deep rip, spring field cultivate.
S.C.N.: medium.

Brownstown
Location: University of Illinois, Brownstown Agronomy Research Center, Fayette County, south central Illinois.
Soil type: Cisne silt loam (poorly drained, gray prairie with a well-developed claypan).
Cooperators: Adam Anderson, research director; Lindell Deal, field worker.
Planting date: May 28.
Harvest dates: September 27 & October 3.
Herbicide: Post-FirstRate, Basagran, Blazer, Poast, Storm, Assure.
Roundup trial: Post- Roundup only.
Tillage: spring combination tillage tool.
S.C.N.: low.

Belleville
Location: Southern Illinois University Research Center, east of Belleville, St. Clair County.
Soil type: Conventional, Weir silt loam. Roundup, Ebbert silt loam.
Cooperators: Dr. Ed Varsa, research director; Ron Krausz, field manager.
Planting date: June 1.
Harvest date: September 30 & October 14.
Herbicide: PPI- Triscept+Treflan+Authority.
Roundup trial: Post- Roundup only.
Insecticide: Warrior (Japanese Beetle).
Tillage: fall chisel, spring disk, & cultimulcher.
S.C.N.: low.

Carbondale
Location: Oval Myers farm, North of Carbondale, Jackson County, extreme southern Illinois.
Soil type: Weir silt loam (shallow, silty loam over claypan).
Cooperators: Dr. Ed Varsa, research director; Paul Pinnon, field manager.
Planting date: May 31.
Harvest dates: September 30, October 2 & 22.
Herbicide: Post-Flexstar, Basagran, Pinnacle.
Roundup trial: Post- Roundup only.
Tillage: spring disk & field cultivate.
S.C.N.: low.

Dixon Springs
Location: University of Illinois Dixon Springs Agricultural Center, Pope County, extreme southern Illinois.
Soil type: Belknap silt loam (light-colored, moderately well-drained, medium-textured bottomland).
Cooperators: Steve Ebelhar, research director; Carl Hart, research specialist.
Planting date: May 28.
Harvest dates: October 2 & 22.
Herbicide: Pre-Authority, Dual II, Post-Flexstar, Fusion.
Roundup trial: Post- Roundup only.
Tillage: spring disk (twice).
S.C.N.: low.

 

2002 Growing Season Rainfall
Location
May
June
July
Aug.
Sept.
Mt. Morris

3.10
7.00
1.80
4.00
1.90
DeKalb
4.64
3.54
1.21
3.06
1.13
Erie
4.30
6.80
2.80
5.60
0.40
Monmouth
7.37
4.44
2.90
5.11
0.41
New Berlin
8.50
3.90
3.70
4.50
1.80
Perry
9.15
4.60
4.75
4.46
0.85
Dwight
2.80
1.10
1.90
0.60
1.30
Goodfield
7.50
2.10
3.00
2.40
0.40
Urbana
6.29
2.78
2.73
7.27
1.77
Brownstown
9.01
3.16
1.21
1.99
1.52
Belleville
6.60
1.74
3.74
3.62
3.38
Carbondale
7.75
2.29
0.10
0.75
2.96
Dixon Springs
9.89
1.23
2.02
2.86
7.50



SOURCES OF SEED