Increasing Soybean Yields by System Management

 

2017 Soybean Management Report Part 1: Yield results (750 KB .pdf of this page)
Part 2: Characterizations (1.9 MB .pdf)

(2016 full report 1 MB .pdf)

 

Based on the Six Secrets of Soybean Success results, we are focusing on how management procedures power yield both individually and interactively with the goal of potentially identifying 'racehorse/offensive' and 'workhorse/defensive' varieties.

 

In 2017, we focused on the interactions of variety, fertility (N, P, and S), and foliar protection at three locations in Illinois (Yorkville, Champaign, and Harrisburg).

 


Research Approach

Understanding soybean yield responses to foliar protection and increased fertility may help producers better position soybean varieties to their anticipated crop management situation. The objective of this study is to identify ‘Offensive’ soybean varieties, or varieties with adaptability to high yield environments (i.e., responsive to crop management), and ‘Defensive’ soybean varieties, or varieties with acceptable yields in low yield environments (i.e., resilience to pests and diseases, and tolerance to nutrient deficiency). In our approach, ‘Offensive’ varieties are the genotypes that combine above-average yield increases from: (i) foliar protection [foliar protection (insecticide and fungicide) versus no-foliar protection], (ii) fertility [187 lbs acre-1 of MicroEssentials S10 (N, P, & S) versus no added fertility], and/or (iii) the combination of both treatments (additional fertility and foliar protection). Conversely, varieties with high yield performance under no additional fertilizer or foliar protection (i.e., the control treatment) and low yield increases from foliar protection were considered ‘Defensive’ varieties.

The 2017 trial evaluated 66 soybean varieties from six different brands comprising maturity groups ranging from 2.5 to 4.8 (Table 1). Thirty-six varieties were evaluated at each of the three locations. The trial was planted using a precision plot planter (SeedPro 360, ALMACO, Nevada, IA) at Harrisburg, IL (10 May 2017), Yorkville, IL (15 May 2017), and Champaign, IL (29 May 2017). Plots were 16 feet in length with 30-inch row spacing and two rows in width to achieve a final population of approximately 160,000 plants acre-1. The foliar protection treatment was applied by tractor and consisted of an insecticide (Endigo® ZC; Lambda-cyhalothrin + Thiamethoxam) and fungicide (Trivapro™; Benzovindiflupyr + Azoxystrobin + Propiconazole) application at the R3 stage at a rate of 3.8 and 13.7 oz per acre, respectively. Application dates for foliar protection were 18 July 2017 (Harrisburg), 27 July 2017 (Yorkville), and 31 July 2017 (Champaign). The fertility treatment consisted of a premium MAP-based phosphorus fertilizer that also contained S, MicroEssentials S10 (MES10, 12-40-0-10S; The Mosaic Company, Plymouth, MN), applied at 187 lbs acre-1 in a subsurface band 4 to 6 inches deep immediately prior to planting using a research-scale fertilizer toolbar to provide 22 lbs N, 75 lbs P2O5, and 18 lbs S per acre.

Plots were arranged in a split-plot RCB design with four blocks. The main plot was fertility (n=2) and the split-plot was foliar protection (n= 2) and variety (n=36) randomly assigned within each treatment block. Data were analyzed using analysis of variance with the PROC MIXED procedure of SAS (Version 8, SAS Institute, Cary, NC) and means were separated using Fisher’s protected LSD test at the 0.10 level of significance. Variety, fertility, and foliar protection were considered fixed effects, while block and interactions with blocks were considered random effects. At maturity, yield (bu acre-1) was measured with a plot combine and adjusted to constant moisture (i.e., 13% grain moisture concentration).

 

Table 1. The evaluation distribution of 66 soybean varieties at Yorkville, Champaign, and Harrisburg, IL in 2017. Varieties are arranged by brand name and maturity group.

Variety

Brand

Maturity Group

Yorkville

Champaign

Harrisburg

AG2636

Asgrow

2.6

X

 

 

AG26X8

Asgrow

2.6

X

 

 

AG27X7

Asgrow

2.7

X

 

 

AG29X8

Asgrow

2.9

X

 

 

AG30X8

Asgrow

3.0

X

 

 

AG32X8

Asgrow

3.2

X

X

 

AG33X8

Asgrow

3.3

X

X

 

AG34X6

Asgrow

3.4

X

X

 

AG36X6

Asgrow

3.6

X

X

X

AG37X8

Asgrow

3.7

 

X

 

AG38X6

Asgrow

3.8

 

X

 

AG38X8

Asgrow

3.8

 

X

 

AG39X7

Asgrow

3.9

 

X

X

AG4135

Asgrow

4.1

 

X

X

AG42X6

Asgrow

4.2

 

 

X

AG43X7

Asgrow

4.3

 

 

X

AG43X8

Asgrow

4.3

 

 

X

AG44X6

Asgrow

4.4

 

 

X

AG46X8

Asgrow

4.6

 

 

X

AG46X6

Asgrow

4.6

 

 

X

AG48X7

Asgrow

4.8

 

 

X

R2C2674

Croplan

2.6

X

 

 

R2C3113

Croplan

3.1

X

X

 

RX3556

Croplan

3.5

X

X

X

RX3896

Croplan

3.8

X

X

X

R2C4000

Croplan

4.1

 

X

X

RX4316s

Croplan

4.3

 

X

X

S26XT88

Dyna-Gro

2.6

X

 

 

S28XT58

Dyna-Gro

2.8

X

 

 

SX17829XT

Dyna-Gro

2.9

X

 

 

S30XT68

Dyna-Gro

3.0

X

X

 

S30XT96

Dyna-Gro

3.0

X

X

 

S31XT48

Dyna-Gro

3.1

X

X

 

S33XT07

Dyna-Gro

3.3

X

X

 

S34XT78

Dyna-Gro

3.4

X

X

 

S35XT97

Dyna-Gro

3.5

X

X

 

S37XT28

Dyna-Gro

3.7

X

X

X

S39XT08

Dyna-Gro

3.9

 

X

X

S39XT68

Dyna-Gro

3.9

 

X

X

S41XS98

Dyna-Gro

4.1

 

 

X

S43XS27

Dyna-Gro

4.3

 

 

X

S44XS57

Dyna-Gro

4.4

 

 

X

SX17844XS

Dyna-Gro

4.4

 

 

X

S45XS37

Dyna-Gro

4.5

 

 

X

S46XS87

Dyna-Gro

4.6

 

 

X

S48XS78

Dyna-Gro

4.8

 

 

X

GH2537X

Golden Harvest

2.5

X

 

 

GH2788X

Golden Harvest

2.7

X

 

 

GH2981X

Golden Harvest

2.9

X

 

 

GH3195X

Golden Harvest

3.1

X

X

 

GH3324X

Golden Harvest

3.3

X

 

 

GH3546X

Golden Harvest

3.5

X

X

X

GH3761X

Golden Harvest

3.7

X

X

X

GH3982X

Golden Harvest

3.9

X

X

X

GH3985X

Golden Harvest

3.9

 

X

X

GH4142X

Golden Harvest

4.1

 

X

X

GH4307X

Golden Harvest

4.3

 

 

X

GH4542X

Golden Harvest

4.5

 

 

X

NK S30-V6

NK

3

X

X

 

NK S37-Z8

NK

3.7

X

X

X

NK S39-C4

NK

3.9

X

X

X

NK S42-P6

NK

4.2

 

X

X

P33T19X

Pioneer

3.3

X

X

 

P36T36X

Pioneer

3.6

X

X

 

P40T26X

Pioneer

4.0

 

X

X

P46T30X

Pioneer

4.6

 

 

X

 

 

Table 2. Precipitation and temperature during the production season at Yorkville, Champaign, and Harrisburg, IL in 2017 compared to the 30-year average (Ave.). Values were obtained from Illinois State Water Survey.

Yorkville, IL

Champaign, IL

Harrisburg, IL

Precip. (in)

Temp. (oF)

Precip. (in)

Temp. (oF)

Precip. (in)

Temp. (oF)

Month

2017

Ave.

2017

Ave.

2017

Ave.

2017

Ave.

2017

Ave.

2017

Ave.

May

4.7

4.3

58

61

5.9

4.9

61

63

4.8

5.1

66

66

June

1.8

4.3

72

70

2.1

4.3

73

72

2.3

4.5

74

75

July

7.0

4.7

74

74

2.8

4.7

76

75

1.2

3.8

79

78

August

2.8

4.1

70

72

2.2

3.9

71

73

4.2

3.0

73

77

Sept.

0.1

3.1

 

68

65

 

0.8

3.1

 

69

66

 

1.5

3.1

 

70

69

 

 

 

 

Table 3. Pre-plant soil properties and Mehlich 3-extraction-based mineral test results obtained from 0 to 6 inches depth for the Soybean Management Yield Potential trial conducted at Yorkville, Champaign, and Harrisburg IL in 2017.

Location

OM

pH

CEC

P

K

Ca

Mg

S

 

%

 

Meg/100g

ppm

 

 

 

 

 

 

 

 

 

Yorkville

5.2

5.8

22.3

43

201

2621

460

9.0

Champaign

2.8

6.3

16.7

33

120

2101

415

7.0

Harrisburg

2.1

6.6

13.2

20

140

2053

166

7.0

† OM, Organic Matter; CEC, Cation Exchange Capacity

 

 

 

 


Yield Results

The 2017 crop growing season experienced excessive rainfall in May at Champaign and Yorkville (Table 2). During the remainder of the growing season (June through September) rainfall was below normal at all three locations, with the exceptions of July in Yorkville (2.3 inches more than the 30-year average) and August in Harrisburg (1.2 inches more than the 30-year average). Throughout the growing season temperatures at all sites were similar to the 30-year average, but August was cooler than normal while September was warmer than normal. Additionally, soil pH, organic matter, and fertility levels were relatively adequate, allowing for growing conditions generally conducive to favorable grain yields (Table 3).

Location significantly affected grain yields, with average yields of 81.8, 62.0, and 90.5 bu acre-1 for Yorkville, Champaign, and Harrisburg, respectively (Tables 4 to 6). Foliar protection tended to increase soybean yields at Yorkville and Harrisburg, but did not increase yield at Champaign due to dry conditions and low disease and insect pressure. On average, foliar protection alone increased yield by +2.5, 0, and +3.5 bu acre-1 at Yorkville, Champaign, and Harrisburg, respectively, while fertility additions alone altered yield by -1.2, +1.4, and +0.8 bu acre-1 at these same sites (Figures 1 to 3). Additional fertility in combination with foliar protection had the largest yield responses in Yorkville (+2.8 bu acre-1) and Harrisburg (+3.8 bu acre-1) compared to fertility or foliar protection alone.

Across all three locations, varieties exhibited significantly different grain yields. At standard management (no fertility additions or foliar protection), highest to lowest yielding varieties differed by 15, 13, and 19 bu acre-1 in Yorkville, Champaign, and Harrisburg, respectively. The largest varietal yield range was from additional fertility in Harrisburg (23 bu acre-1).

The highest yields recorded were 91.0, 70.3, and 103.8 bu acre-1 at Yorkville, Champaign, and Harrisburg, respectively (varieties R2C2674, AG36X6, and NK S39-C4, respectively) observed when the plants were grown under increased fertility plus foliar protection conditions. In Yorkville, the top five yields were from the following varieties: R2C2674 (91.0 bu acre-1), GH3195X (90.4 bu acre-1), GH2981X (89.4 bu acre-1), S28XT58 (89.3 bu acre-1), and GH2788X (89.0 bu acre-1), all achieved with foliar protection plus fertility. Moving down the state of Illinois, the top five yields in Champaign were achieved with the following varieties: AG36X6 (70.3 bu acre-1), AG34X6 (68.6 bu acre-1), AG4135 (68.5 bu acre-1), P40T26X (68.2 bu acre-1), and AG32X8 (67.3 bu acre-1). Harrisburg achieved the highest overall yields with: NK S39-C4 (103.8 bu acre-1), NK S42-P6 (103.2 bu acre-1), S41XS98 (100.3 bu acre-1), AG39X7 (98.2 bu acre-1), RX3556 (97.9 bu acre-1), and S37XT28 (97.9 bu acre-1).

Yield responses of individual varieties to additional fertility compared to the untreated control at all locations ranged from -7.6 to +8.4 bu acre-1, indicating different genetic sensitivity to soil nutrient availability. Foliar protection changed yield by -5.8 to +11.4 bu acre-1, and when applied in combination with fertility, yields changed by -7.1 to +12.3 bu acre-1.

The differences observed in yield performance among varieties and their interaction with agronomic management across environments highlights the importance of soybean genetic characterization in response to different agronomic factors. These characterizations will be summarized in a more in-depth report to follow.

Table 4. Grain yield of 36 commercial soybean varieties in response to fertilizer and foliar protection at Yorkville, IL in 2017. Within a seed brand, varieties are sorted by maturity group. Values are the average of four replications.

 

Foliar Protection

 

Without

With

 Fertilizer (lbs acre-1)

Variety

0

187

0

187

Asgrow

 

 bu

acre-1

 

AG2636

85.5

81.0

86.2

83.7

AG26X8

84.8

86.0

85.3

85.2

AG27X7

78.7

79.4

79.5

85.2

AG29X8

77.1

80.1

77.4

81.2

AG30X8

77.3

76.2

78.2

82.8

AG32X8

82.4

82.0

87.1

87.2

AG33X8

80.2

79.5

80.9

78.9

AG34X6

77.8

75.6

84.2

82.0

AG36X6

79.5

79.1

79.3

81.4

Croplan

 

 

 

 

R2C2674

84.5

85.5

87.2

91.0

R2C3113

80.5

78.7

83.0

85.0

RX3556

80.8

80.6

82.2

85.0

RX3896

71.6

70.9

77.4

75.7

Dyna-Gro

 

 

 

 

S26XT88

78.0

78.5

78.3

78.6

S28XT58

83.4

84.5

86.8

89.3

SX17829XT

81.0

81.1

85.4

84.2

S30XT68

85.5

78.5

87.6

86.5

S30XT96

81.5

83.1

87.0

85.3

S31XT48

75.0

81.3

83.7

82.8

S33XT07

81.7

77.0

81.4

78.2

S34XT78

84.5

82.3

84.6

85.6

S35XT97

81.1

78.0

82.5

80.8

S37XT28

79.6

83.4

83.8

83.2

Golden Harvest

 

 

 

 

GH2537X

82.2

81.1

86.3

83.8

GH2788X

86.8

85.6

89.0

89.0

GH2981X

78.7

80.6

86.1

89.4

GH3195X

86.3

85.8

85.2

90.4

GH3324X

79.7

82.5

79.4

81.3

GH3546X

84.2

80.8

84.7

88.8

GH3761X

80.8

74.9

87.2

82.9

GH3982X

75.4

67.7

86.2

79.7

NK

 

 

 

 

NK S30-V6

79.7

74.8

83.3

84.8

NK S37-Z8

80.7

76.4

84.0

84.7

NK S39-C4

81.4

76.0

75.6

74.2

Pioneer

 

 

 

 

P33T19X

84.7

83.7

81.6

80.5

P36T36X

76.3

73.5

81.6

81.4

 

Overall Mean

80.8

79.6

83.3

83.6

Range

72-87

68-86

76-89

74-91

 

 

 

 

 

LSD (P ≤ 0.10)

4.8

5.9

5.6

5.9

 

Variation of soybean yields at Yorkville

Figure 1. Yield response to fertility (yield difference between 0 and 187 lbs acre-1 of MES10), foliar protection [yield difference between foliar protection (insecticide and fungicide) and no foliar protection], and the combination of fertility and foliar protection (yield difference between control and 187 lbs acre-1 of MES10 with foliar protection) for 36 soybean varieties grown at Yorkville, IL in 2017.

 

 

Table 5. Grain yield of 36 commercial soybean varieties in response to fertilizer and foliar protection at Champaign, IL in 2017. Within a seed brand, varieties are sorted by maturity group.

 

Foliar Protection

 

Without

With

 Fertilizer (lbs acre-1)

Variety

0

187

0

187

Asgrow

 

 bu

acre-1

 

AG32X8

66.1

63.2

67.3

61.9

AG33X8

60.7

61.9

61.1

60.7

AG34X6

68.6

66.9

66.4

65.3

AG36X6

62.6

64.3

68.7

70.3

AG37X8

66.6

66.0

62.4

63.4

AG38X6

59.2

62.7

58.5

62.1

AG38X8

57.5

55.9

57.3

54.5

AG39X7

63.8

65.4

59.8

63.2

AG4135

68.5

68.5

68.5

67.6

Croplan

 

 

 

 

R2C3113

64.3

64.1

61.0

63.1

R2C4000

61.7

65.0

64.1

63.6

RX3556

65.5

62.9

63.1

62.7

RX3896

59.3

63.9

60.5

65.0

RX4316s

65.0

66.1

64.0

62.8

Dyna-Gro

 

 

 

 

S30XT68

62.1

64.7

61.9

65.8

S30XT96

59.6

63.3

56.9

57.9

S31XT48

62.9

65.4

61.0

64.0

S33XT07

61.3

67.0

61.2

61.4

S34XT78

65.1

62.4

62.9

64.3

S35XT97

60.5

64.5

59.6

66.1

S37XT28

61.1

62.6

59.4

61.0

S39XT08

54.4

53.7

53.9

54.5

S39XT68

64.7

65.3

63.1

62.3

Golden Harvest

 

 

 

 

GH3195X

61.9

64.5

62.6

65.6

GH3546X

63.2

59.6

62.4

61.7

GH3761X

61.8

59.1

62.6

59.3

GH3982X

64.9

65.2

65.3

66.1

GH3985X

54.4

55.6

56.2

57.7

GH4142X

57.7

62.7

57.7

60.0

NK

 

 

 

 

NK S30-V6

58.1

59.7

59.4

60.2

NK S37-Z8

61.0

66.0

60.9

59.6

NK S39-C4

54.9

57.4

57.5

60.2

NK S42-P6

57.8

59.2

59.2

58.7

Pioneer

 

 

 

 

P33T19X

61.2

64.5

59.1

60.5

P36T36X

55.9

60.6

57.6

58.7

P40T26X

59.7

64.9

61.2

68.2

 

 

 

 

 

Overall Mean

61.5

62.9

61.2

62.2

Range

54-67

54-69

54-69

55-70

 

 

 

 

 

LSD (P ≤ 0.10)

6.0

7.5

6.9

7.4

 

Yield variation at Champaign in 2017

 

Figure 2. Yield response to fertility (yield difference between 0 and 187 lbs acre-1 of MES10), foliar protection [yield difference between foliar protection (insecticide and fungicide) and no foliar protection], and the combination of fertility and foliar protection (yield difference between control and 187 lbs acre-1 of MES10 with foliar protection) for 36 varieties of soybean grown at Champaign, IL in 2017.

 

Table 6. Grain yield of 36 commercial soybean varieties in response to fertilizer and foliar protection on soybean grain yield at Harrisburg, IL in 2017. Within a seed brand, varieties are sorted by maturity group.

 

Foliar Protection

 

Without

With

 Fertilizer (lbs acre-1)

Variety

0

187

0

187

Asgrow

 

 bu

acre-1

 

AG36X6

86.7

87.5

93.8

96.7

AG39X7

88.8

92.4

98.2

95.6

AG4135

90.2

90.1

97.0

95.3

AG42X6

87.6

90.3

92.6

95.9

AG43X7

86.8

88.3

86.8

91.6

AG43X8

87.8

83.6

93.1

91.7

AG44X6

81.0

89.5

89.0

93.2

AG46X8

88.5

88.7

92.9

92.5

AG46X6

86.0

84.6

80.7

85.2

AG48X7

79.8

79.9

78.9

92.1

Croplan

 

 

 

 

RX3556

94.6

94.4

97.0

97.9

RX3896

85.4

85.6

91.3

90.0

R2C4000

90.7

88.1

93.1

92.6

RX4316s

86.8

88.1

89.6

88.9

Dyna-Gro

 

 

 

 

S37XT28

96.4

96.9

97.9

96.9

S39XT08

87.3

82.1

90.5

91.6

S39XT68

84.3

89.9

95.7

95.6

S41XS98

90.7

94.6

97.4

100.3

S43XS27

88.4

87.6

92.2

87.7

S44XS57

88.5

89.4

92.9

90.1

SX17844XS

88.3

86.0

91.0

90.2

S45XS37

93.2

90.9

94.2

92.2

S46XS87

82.9

86.5

84.0

85.9

S48XS78

87.7

83.9

88.4

85.7

Golden Harvest

 

 

 

 

GH3546X

90.6

92.1

96.5

93.1

GH3761X

89.9

95.0

95.1

92.8

GH3982X

89.8

91.9

93.7

91.0

GH3985X

82.6

86.3

87.3

89.6

GH4142X

78.6

81.9

84.2

83.8

GH4307X

92.9

93.1

94.0

94.8

GH4542X

88.3

87.9

89.1

90.1

NK

 

 

 

 

NK S37-Z8

94.5

90.7

91.8

95.5

NK S39-C4

95.3

95.6

98.3

103.8

NK S42-P6

98.1

103.2

98.6

94.6

Pioneer

 

 

 

 

P40T26X

85.7

86.1

87.7

90.7

P46T30X

90.7

92.9

95.2

88.4

 

 

 

 

 

Overall Mean

88.5

89.3

91.9

92.3

Range

79-98

80-103

79-99

88-104

 

 

 

 

 

LSD (P ≤ 0.10)

5.9

6.2

5.1

5.7

 

Yield changes at Harrisburg

 

Figure 3. Yield response to fertility (yield difference between 0 and 187 lbs acre-1 of MES10), foliar protection [yield difference between foliar protection (insecticide and fungicide) and no-foliar protection], and the combination of fertility and foliar protection (yield difference between control and 187 lbs acre-1 of MES10 with foliar protection) for 36 varieties of soybean grown at Harrisburg, IL in 2017.