Key Management Practices That Explain Soybean Yield Gaps Across The North Central U.S. - Shawn Conley, from the 2018 Conservation Tillage and Technology Conference, March 6 - 7, Ada, OH, USA. More presentations at https://www.youtube.com/channel/UCZBwPfKdlk4SB63zZy16kyA

1. Key Management Practices That
Explain Soybean Yield Gaps Across
the North Central U.S.
Mourtzinis, S., J.I. Rattalino Edreira, P. Grassini, A. Roth, S.
Casteel, I. Ciampitti, H. Kandel, P. Kyveryga, M. Licht, L.
Lindsey, D. Mueller, E. Nafziger, S. Naeve, J. Stanley, M. Staton,
S.P. Conley

2. 2017 WI Soybean Program in Review

4. Pooled Herbicide Trait Performance Across
Southern, Central and North Central WI 2017

5. Pooled White Mold Incidence at ARL, HAN, &
CHIP FALLS Sites Across Herbicide Traits 2017

6. 2017 Regional Starred Varieties as % of
Varieties in Each Event

7. Assessing causes of yield gaps
US soy area is ± 85 million a
and the ~30% of global
soybean production
USDA-NASS (2011-2015)
North-Central US region
represents the ~80% US
soybean production
Potential yield:
90 bu/ac
Actual gap:
45 bu/ac
Specht et al. (1999)FAOstat (2011-2015)
Main goal
To benchmark current yield and management practices in producer fields
across the North-Central US region in order to identify KEY management
factors that can help producers to increase yield and input-use efficiency

8. Data collection: survey formFarmer data
Location of surveyed 2014-2015 soybean fields
Number of fields: 3568

9. The team

10. Data collection: survey formData collection: survey form

11. Materials and Methods
• Average pH values for topsoil (0-12 inches) and subsoil (12-60
inches) for each field were derived from the SSURGO database.
• To account for differences in slope and terrain across field, which
could influence the crop water balance, we calculated average
values of topography wetness index (TWI) for each field.
• Fields with large TWI values would be associated with greater
water supply and fertility compared with fields with lower values.

12. Rainfed field in central NE Rainfed field in central IA
Annual rainfall: (24 in)
Soil type: silt loam
IA
Annual rainfall: (35 in)
Soil type: clay loam
How to make fair comparisons among fields?
We hypothesize that collecting producer field data is equivalent to running field
experiments to capture responses to management factors IF fields are properly
contextualized relative to climate and soil.

13. Materials and Methods cont.
• Briefly, TED framework delineates regions based on:
(i) annual total growing degree-days,
(ii) aridity index,
(iii) annual temperature seasonality, and
(iv) plant-available water holding capacity in the rootable soil depth.
• Each TED corresponds to a specific combination of the four
parameters.

14. Surveyed fields were clustered in 10 TEDs; each TED contains > 90 fields
Field Survey Data & Technology Extrapolation Domain (TED)

15. Management Practices Defined
April 30

16. Management practices cont.

17. Management practices cont.

18. Management practices cont.

20. What is the soybean yield gap in the NC USA region?
Soybean yield gap in the NC USA were relatively small, averaging 22% (rainfed;
67 vs 52 bu/a) and 13% (irrigated; 82 vs 74 bu/a) of the estimated yield potential.
(Rattalino Edreira et al. 2017a,
Agric. For. Meteorol. 247, 170-180)

21. Management factors influencing yield in your TED?

22. Late soybean planting reduces
yield potential up to 0.5 bu a-1 per
day of delay after late April, but
the magnitude of yield penalty
varies across TEDs.
Influence of planting date on soy yield by TED
(Rattalino Edreira et al. 2017a,
Agric. For. Meteorol. 247, 170-180)

23. Water deficit influence in potential response to planting date
Yield penalty (or response) to sowing date was negligible when water
deficit was < -4 in, but increased linearly up to nearly ~1 in
(Rattalino Edreira et al. 2017a,
Agric. For. Meteorol. 247, 170-180)

24. SDS: An Unintended Partner of Early
Planted Soybeans
• Fusarium virguliforme causes
sudden death syndrome of
soybean
• Delaying planting has shown
to reduce SDS symptoms, but
it can also reduce soybean
yield
F. virguliforme spores

25. Yield Results by
Planting Date (2013-14)

26. Trial Information
• RCBD 2 x 3 x 6 factorial or split plot with 4 reps
• Varieties used: AG2136, RS213NR2, AG2636
• WI, IA, IN, MI, ON
• Six seeding rates (seeds a-1)
– 40,000
– 60,000
– 80,000
– 100,000
– 120,000
– 140,000 (current WI rec.)
• Three seed treatments
– UTC
– CB (Commercial Base)
– Prothioconazole (F)
– Penflufen (F)
– Metalaxyl (F)
– Clothianidin (I)
– Bacillus firmus (N)
– ILeVO
– CB (FIN)
– Fluopyram (F)

27. Seed Treatment Breakdown
Seed treatment
code†
Seed treatment
trade name(s) Active ingredients (a.i.)‡
Application
rate
mg a.i. seed-1
UTC n/a - -
CB EverGol™
Energy + prothioconazole (F) 0.0083
(Commercial penflufen (F) 0.0041
Base) metalaxyl (F) 0.0066
Allegiance FL + metalaxyl (F) 0.02
Poncho®
/VOTiVO®
clothianidin (I) 0.1074
Bacillus firmus (N) 0.0218
ILeVO EverGol™
Energy + prothioconazole (F) 0.0083
penflufen (F) 0.0041
metalaxyl (F) 0.0066
Allegiance FL + metalaxyl (F) 0.02
Poncho®
/VOTiVO®
+
clothianidin (I) 0.1074
Bacillus firmus (N) 0.0218
ILeVO®
fluopyram (F) 0.15
† Seed treatment code represents the unique combination of active ingredients. The
letters/numbers were used for coding each seed treatment.
‡ F: fungicide; I: insecticide; N: nematistat.
1

28. Yield Potential: Locations
• We examined
treatments across
various yield potentials
and ultimately,
responsive and non-
responsive
environments
– WI = 20 environments
– IA = 2 environments
– IN = 1 environment
– MI = 1 environment
– ON = 2 Environments
= Location displayed
visual SDS symptomology

29. Trial Information
• Data was broken into 6 different data sets as
follows:
– WI All, contains all WI locations, regardless of SDS
symptomology
– WI SDS, contains WI location with visual SDS
symptomology (7/20 LOCATIONS)
– IA, IN, MI and ON locations all displayed visual SDS
symptomology but were analyzed separately due to
experimental designs differences.

30. Early Season Plant Stand (V2)
*

31. BeanCam Replant Decision App.

32. Replant Decision App.

33. Main Effect: Seeding Rate
LSD (0.05) 0.9 8.95.710.22.61.5
WI All WI SDS IA IN MI ON
Yield(bua-1
)
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
40,000
60,000
80,000
100,000
120,000
140,000

34. Main Effect: Seed Treatment
WI All WI SDS IA IN MI ON
Yield(bua-1
)
50
55
60
65
70
75
80
85
90
95
UTC
CB
ILeVO
a
b
c b b
b b
b
a
a
a
a
a
a
a
a
a
a

35. Yield at Various Seeding Rates for the
Different Seed Treatments
Seeding Rate (1000 seeds a-1
)
40 60 80 100 120 140
Yield(bua-1
)
60
65
70
75
80
UTC, R2
= 0.95, S.E. = 1.52
CB, R2
= 0.96, S.E. = 1.33
ILeVO, R2
= 0.97, S.E. = 1.28

36. Economic Risk Table for $8 bu-1 Soybeans
Treatment combination
Break-even
probability
Avg. profit increase over the Base Case
Seed
Treatment
Seeding
Rate
Positive
outcomes
All
outcomes
Negative
outcomes
Seeds a-1 _____________________$ a-1_____________________
UTC 120,000 0.99 4 4 na
100,000 0.97 3 3 -1
80,000 0.04 1 -5 -6
60,000 0.00 na -32 -32
40,000 0.00 na -96 -96
CB 140,000 0.70 6 4 -4
120,000 0.93 10 9 -3
100,000 0.97 11 11 -2
80,000 0.76 6 4 -3
60,000 0.01 2 -20 -21
40,000 0.00 na -83 -83
ILeVO 140,000 0.87 9 7 -3
120,000 0.98 14 14 -2
100,000 0.99 16 16 -2
80,000 0.95 9 9 -2
60,000 0.01 3 -17 -17
40,000 0.00 na -83 -83
EOSR
UTC 110,300 0.99 4 4 0
CB 103,700 0.97 11 11 -2
ILeVO 103,200 0.99 16 16 -2

37. Results TED=1R

38. Results TED=1R

39. Results TED=2R

40. Results TED=2R

41. Results TED=5R

42. Results TED=5R

43. Results TED=6R

44. Results TED=6R

45. The New SCN Coalition
The New SCN Coalition: Why Now?
June 2017

46. 2018 48
The New SCN Coalition
A new generation of soybean cyst nematode
is born every 24 days during summer.
Many overpower resistant soybeans.
All will cut yield potential.

47. www.coolbean.info
@badgerbean
thesoyreport.blogspot.com