‡2006 – 2017 quality

estimates are weighted

by yearly production

estimates by state

We

Can Agronomic Management Simultaneously Increase

Protein Concentration and Yield in Soybean?Vitor Rampazzo Favoretto and Frederick E. Below

Crop Physiology Laboratory, Department of Crop Sciences, University of Illinois at Urbana-Champaign

• Soybean [Glycine max (L.) Merr.] grain is important for theagricultural industry because of its sub-product meal, providingprotein for animal production.

• Soybean grain protein concentration (quality) has been decreasing,due to the modern crop management focus on yield (Figure 1).

1. Can individual agronomic management simultaneously increase seedprotein concentration and yield in soybean?☓ No, Soybean had greater yield, but similar or lower concentrations of

grain protein when the management factors of narrow row spacing, full RM, foliar protection, P & K, or seed treatment were added individually.

2. Do multiple agronomic management inputs synergistically andsimultaneously increase seed protein concentration and yield in soybean?☓ No, The High Input approach, where management factor treatments are

applied together was beneficial to yield, but seed protein concentrationwas usually lower.

Identify independent and/or synergistic contributions of agronomic management factors to soybean seed protein level and yield.

• Using Full-season RM varieties increased yield on average by0.27 Mg ha-1 (Table 2). Because grain protein concentrationwas not consistently affected by maturity, the proteinproduction increases by Full RM varieties were mainly drivenby yield differences (Table 2).

Sites Five trials were conducted in two years (2015, 2016) and atone of four locations (DeKalb (42oN), Yorkville (41oN) Champaign(40oN), and Harrisburg (37oN) in Illinois. Plots were 4-rows x 11min length, in which the center 2 rows were harvested for yield witha plot combine. A grain sample was collected from each plot andgrain protein concentration was determined by NIT. Proteinproduction was estimated from yield and grain proteinconcentration, and all values are expressed at 13% moisture.

An omission-addition plot design was used to evaluate thecontribution of different management factors (Table 1), describedbelow. All treatments were replicated 6 times.

Fertilizer

• No external addition to natural soil fertility, or

• Addition of phosphorus (P) and potassium (K) using a MAP-based P fertilizer (MicroEssentials-SZ 12-40-0-10S-1Zn), banded15 cm deep directly prior to planting at a rate of 84 kg P2O5 ha-1,and a MOP-based K fertilizer (Aspire, 0-0-58-0.5B), broadcastdirectly prior to planting at a rate of 84 kg K2O ha-1.

Foliar Protection

• Fungicide and insecticide mixes, QuadrisTop + Endigo(Syngenta) or Priaxor + Fastac (BASF), were used and comparedto no foliar applications. The treatment was applied at the R3growth stage using a CO2-propelled backpack applicator.

Seed Treatment

• No seed treatment (naked seed) or fungicide-only seedtreatment was compared to a full seed treatment (fungicide,insecticide and nematicide), with the specific seed-treatmentproducts dependent upon the seed brand that was used.

Row Spacing

• Two row spacings of 51 or 76 cm, in both cases at a final standof 395,000 plants ha-1.

Relative Maturity (RM)

• A normal and a full-season variety (differing by 0.3 RM units)for the geographic region were included in each trial.

MANAGEMENT FACTORS

Treatment P & K Foliar Protection Seed treatment

HIGH INPUT Yes Yes Full

Om

itM

an

ag

em

en

t

-P and K None Yes Full

-Foliar Protection Yes None Full

-Seed Treatment Yes Yes Basic

STANDARD None None Basic

Ad

d

Ma

na

ge

me

nt

+P and K Yes None Basic

+Foliar Protection None Yes Basic

+Seed Treatment None None Full

Table 1. The omission-addition design used to evaluate individual management factortreatments from Standard or High Input management systems. All treatments wereevaluated using two relative maturity cultivars in 51 and 76 cm rows.

Table 2. Soybean yield, grain protein concentration, and protein production as afunction of variety maturity group (Normal or Full) for each site year. Values areaveraged over two management input levels and two row spacing.

Table 3. Soybean yield, grain protein concentration, and protein production as afunction of different row spacing (51cm and 76 cm) for each site year. Values areaveraged over two management input levels and two cultivars.

33

33.5

34

34.5

35

35.5

36

36.5

0500

1000150020002500300035004000

Pro

tein

(%

)

Yie

ld (

kg

.ha

-1)

YearYIELD (Kg\ha) PROTEIN (%)

Source: USSEC

‡2006 – 2017 quality estimates are weighted by yearly production estimates by state

Site-Year Yield Protein Protein production

51 cm 76 cm 51 cm 76 cm 51 cm 76 cmMg ha-1 % Mg ha-1

DeKalb 2015 4.6† 3.9 34.5 34.7† 1.6† 1.4Champaign 2015 6.3† 5.6 33.6 33.7 2.1† 1.9

Yorkville 2016 6.3† 5.3 35.6 35.6 2.2† 1.8Champaign 2016 5.1† 4.6 34.7 34.9 1.8† 1.6Harrisburg 2016 4.2† 3.8 35.1 35.4† 1.5† 1.3

† Significant difference between row spacing within a site-year at α = 0.1

Site-YearYield Protein Protein production

Normal Full Normal Full Normal FullMg ha-1 % Mg ha-1

DeKalb 2015 4.2 4.4† 34.7 34.4 1.5 1.5†Champaign 2015 5.9 6.1† 33.6 33.7 2.0 2.1†

Yorkville 2016 5.8 5.8 35.7 35.6 2.1 2.1Champaign 2016 4.7 5.0† 34.5 35.2† 1.6 1.8†Harrisburg 2016 4.1 3.9† 35.7 34.8† 1.5 1.4†

† Significant difference between maturity groups within a site-year at α = 0.1

Figure 3. Soybean yield (a), grain protein concentration (b), and protein production (a), as a function ofdifferent management factor additions or diminishments. Values are the average of all five site years, eachwith two RM varieties and two row spacings.

• Foliar protection or P&K increased yield and protein productionwhen added to the Standard system (Figure 3a), but decreasedprotein concentration (Figure 3b). Conversely, omitting P&K fromthe High Input system decreased yield and protein production, butincreased protein concentration.

Figure 2. Soybean yield (a), grain protein concentration (b), and protein production (a) as a function of Standard or High Input management. Values are the average of all five site years, each with two RM varieties and two row spacings.

Figure 1. Average soybean yield (kg ha-1) and grain protein (%) for the United Statesover crop years from 1986 to 2016.

D C C C A AB B AB

d

cc

cd

a

abb

ab

1.5

1.6

1.7

1.8

1.9

2.0

2.1

4.5

5.0

5.5

6.0

Standard +Foliar +P & K +Seedtreatment

HighInput

-Foliar -P & K -Seedtreatment

Pro

tein

pro

duction (

Mg h

a-1

)

Yie

ld

Mg h

a-1

)

Yield Protein production

(a)

• Decreasing row spacing from 76 to 51 cm was beneficial foryield (with an average gain of 0.65 Mg ha-1), but decreasedgrain protein concentration by an average of 0.2 percentagepoints (Table 3). Thus, the increase in protein production(average gain of 0.22 Mg ha-1) from narrow rows was driven bythe increase in grain yield (Table 3).

• The addition of all management factor treatments (High Input)increased yield by an average of 0.4 Mg ha-1 (Figure 2a), butdecreased grain protein concentration by 0.25 percentagepoints (Figure 2b). However, overall protein production wasstill higher with the High Input management (Figure 2a).

B A

b

a

1.7

1.8

1.9

2

2.1

4.5

5

5.5

6

Standard High Input

Pro

tein

Pro

duction (

Mg h

a-1

)

Yie

ld (

Mg h

a-1

)

Yield Protein Production

(a)

Uppercase letter shows differences in Yield at α= 0.1

Lowercase letter shows differences in Protein production at α= 0.1

A

B

33.5

33.8

34.1

34.4

Standard High Input

Pro

tein

(%

)

(b)

Uppercase letter shows differences in Protein at α= 0.1

33.5

33.8

34.1

34.4

Standard +FoliarProtection

+P & K +Seedtreatment

High Input -FoliarProtection

-P & K -Seedtreatment

Gra

in P

rote

in (%

)

(b)A

A A

B

BCBC

C

A

Uppercase letter shows differences in Protein at α= 0.1

Lowercase letter shows differences in Protein production at α= 0.1

Uppercase letter shows differences in Yield at α= 0.1

Thanks to Mosaic, Syngenta, BASF, Bayer CropScience, Winfield

United, The Illinois Soybean Association, and The United

Soybean Board for supporting this research.