Make Wheat Great Again: The
Potential of Perennial Wheat
Jamie Larsen
AAFC-Lethbridge
Do You Ever Regret Writing or Saying Something?
• Wheat is a great crop. Always
was…always will be
• We need it:
– For food
– For sustainability of the
agriculture system
• Great long term plot work
tells us this very clearly
– Dr. Dave Hooker
– Dr. Bill Deen
– Peter Johnson
From: Dr. Bill Deen via twitter
From: Dr. Dave Hooker via twitter
Outline
• Capitalizing on environmental benefits
• Types of perennial wheat
• Summary of biomass and grain yield data
• The business case for perennial wheat
• Perennial wheat production system
• Social benefits of perennial wheat
• Development of perennial wheat
Perennial Cereals vs. Annual Cereals
Perennials
• Trade-off theory
• Two sinks for
photosynthetic products
– Crown and roots for
survival
– Grain
• Lower grain yield
• Access to more
resources
– Capture more of the sun’s
energy per year
– Large roots access more
water and nutrients
Cox et al. 2005
0% 25% 50% 75% 100%
rangeland
wheat
proportion of annual NPP
below ground
above residue
above harvested
Annuals
• Go for broke
• One sink for
photosynthetic
products
– Grain
• Capture less sun
energy per year
• Selection for yield
over 10,000 years
Perennial Cereal Crops Have Many Advantages
Over Annual Cereal Crops• Make use of full season moisture
• Reduce nutrient run-off
• Improve soil quality by increasing soil organic matter
• Limit soil erosion through reduced tillage and constant cover
• Make use of soil biology/ plant interactions
• Minimize herbicide application
• Reduce seeding costs
• Potential benefits for mixed farming operations
• Constant capture of sunlight
Utilization of Soil Moisture by Perennials
• In comparison to annual
wheat:
– Perennials take up more
soil moisture including at
peak productive periods
– Perennials make use of
soil moisture to greater
depths
• Attributed to large roots
systemFrom Cutforth et al 2005From Glover et al. 2010
Ability to Limit Nitrogen Leaching and Run Off
• Spring wheat roots are
only able to access N and
water to 120 cm
• Data shows the ability of
Alfalfa and Crested
Wheatgrass to use N
twice as deep as spring
wheat
From Cutforth et al 2010
Soil Organic Carbon-Time lapse
• All systems approach some level of stasis– Finite amount of SOC can be
stored
– Based on many factors
• Conversion to arable farming caused a loss of SOC
• No-till led to less soil disturbance and often increased carbon sequestration but not to the original levels of pre-agriculture
From Janzen et al. 1998
Perennial Wheat?
annual wheat on fallow
perennial grass
macro
organic matter
= MOM
9
Relative Global Warming Potential (GWP) of
Agriculture (from Robertson et al 2000)
• GWP is a relative measure of how much heat a greenhouse gas traps in the atmosphere
• Expressed as grams of CO2 equivalents/m2/year
CO2
Ecosystem management N2O CH4 Net
N GWP
Soil C fertilizer Lime Fuel
Annual Crops (C-S-W)
Conventional tillage 0 27 23 16 52 -4 114
No till -110 27 34 12 56 -5 14
Low input w legume cover -40 9 19 20 60 -5 63
Organic w legume cover -29 0 0 19 56 -5 41
Perennial Crops
Alfalfa -161 0 80 8 59 -6 -20
Poplar -117 5 0 2 10 -5 -105
Extrapolated
potential?
Perennial Wheat -161 27 34 8 56 -5 -41
TYPES OF PERENNIAL WHEAT
Development of Perennial Wheat
• ‘Perennial’ depends on your
perspective (2 to ∞ years)
• Two types
– Kernza (domesticated
intermediate wheatgrass)
– Perennial wheat (wheat x
wheatgrass hybrid)
• Targeting 3 years with minimal
drop off in productivity
• Grain yield target
– 80%-90% or winter wheat
Types of Perennial Wheat
Kernza
• Domesticated Intermediate Wheatgrass (Th. intermedium)
• Breeding programs– The Land Institute (Kansas)
– U. of Manitoba
– U. of Minnesota
• Impressive rapid improvement
• In commercial production
• Grain quality is similar to soft wheat
T. aestivum Wheat x Wheatgrass Kernza Th. intermedium
(Bread wheat) hybrid (Wheatgrass)
Types of Perennial WheatPerennial wheat
• Wheat x Wheatgrass crosses
• Sources of Perennial Habit
• Tall wheatgrass (Th. ponticum and Th.
elongatum)
• Kernza
• Chromosome numbers: 14, 42, 56, 70
• Triticale model
- 42 wheat (bread) + 14 wheatgrass
- 28 wheat (durum) + 28 wheatgrass
- 28 wheat (durum) + 14 wheatgrass
T. aestivum Wheat x Wheatgrass Domesticated Th. intermedium
(Bread wheat) hybrid Th. intermedium
GRAIN YIELD AND BIOMASS DATA
FROM PERENNIAL WHEAT TRIALS
• Assumed yield of perennial wheat was 60% of annual
wheat in Australia
• Combined with sheep for grazing of regrowth
The Business Case of Perennial Wheat (Bell et al 2007)
Scenario Farm Perennial Crop Pasture Stocking Supplementary
profit wheat area area rate feed
per ha (ha) (ha) (ha) (dse/ha) (kg/dse)
Without 55.6 0 1100 900 7.6 59.4
Perennial wheat
With 76.5 400 900 1100 8.9 58.4
Perennial wheat
Change +20.9 +400 -200 +200 +1.3 -1.0
Perennial Cereal Rye Biomass and Grain Data
Grain Test Thousand Ergot Falling Protein
Treatment Yield weight Kernal wt. number
(t/ha) (kg/hL) (g) (%) (s) (%)
Early-grain 1.2 65.5 22.8 31.9 297.0 12.2
Boot-grain 0.9 n.d. 22.7 44.5 306.0 11.8
Grain 2.5 67.1 25.8 10.4 261.3 12.9
P-value 0.01 0.26 0.03 0.001 0.08 0.34
Tukey 0.86 n.s. 2.67 10.45 n.s. n.s.
0102030405060708090100
05000
100001500020000250003000035000
Bio
mass y
ield
(kg/h
a)
2014 W
inte
r S
urv
ival (%
)
Cutting Treatment
18
Kernza Dual-Use Pilot Study
• Objectives:
– Document Kernza forage and grain yields over range of
environments
– Determine the effects of defoliation on grain yields, plant
height and forage dry matter and quality
• Led by Dr. Steve Culman at Ohio State with multiple
trial sites across the US and Canada
– No cut (grain yield only)
– Control = Summer cut after grain harvest
– Spring cut + summer cut after grain harvest
– Fall cut + summer cut after grain harvest
From: S. Culman, OSU
From: S. Culman, OSU
Grain Yields
Colorado Kansas Minnesota New York Western OH Wooster OH Iowa Maryland Wisconsin
0
500
1000
1500
2000
2015
2016
2015
2016
2015
2016
2015
2016
2015
2016
2015
2016
2015
2016
2015
2016
2015
2016
Year
Gra
in Y
ield
(kg
/ha
)
Year
2015
2016
Average Grain Yields Over All
Sites:
2015 = 704 kg/ ha
2016 = 363 kg/ ha
From: S. Culman, OSU
Grain Yields with Defoliation Treatment
Colorado Kansas Minnesota New York Western OH Wooster OH
0
300
600
900
0
300
600
900
2015
20
16
Con
trol
Spr
ing
Fall
Con
trol
Spr
ing
Fall
Con
trol
Spr
ing
Fall
Con
trol
Spr
ing
Fall
Con
trol
Spr
ing
Fall
Con
trol
Spr
ing
Fall
Clip
Gra
in Y
ield
(kg/h
a)
Clip
Control
Spring
Fall
a b
a bb
From: S. Culman, OSU
Preliminary Conclusions
• Yields vary widely across sites
• Spring clip didn’t reduce grain yield
• Fall clip appears to increase grain yield
Perennial Wheat Trials
• Grown under irrigation at Lethbridge, AB
• Short rows replicated three times
• Best perennial wheat germplasm that currently exists
• Comparison to winter wheat and Kernza
• Part of a larger experiment with trials located around the
world
Wheat x Wheatgrass study
Parental Lines Plot yield Relative Relative TKW Height Regrowth
(kg/ha) Yield Biomass (g) (cm) Score
Th. elongatum 7692 74 196 26 99 18
Th. intermedium 5224 51 150 28 87 14
Th. ponticum 6941 67 160 26 96 20
PC Rye 5820 56 162 31 101 20
Kernza 541 5 162 10 102 22
Annual Wheat 10331 100 100 39 76 3
Perennial Wheat Conclusions-First Year
• All perennial wheat lines yielded less grain than annual
wheat (~64% of annual)
• Perennial lines yielded much more biomass than annual
wheat line due to increase height (~161% of annual)
• Regrowth scores from perennial wheat lines were
higher
• We’ll see what next year brings!
THE BUSINESS CASE FOR
PERENNIAL WHEAT
Business Case Based on Real Perennial Wheat Data
• OMAFRA enterprise budgets for costs
• Used relative perennial wheat yield (0.64) to calculate grain
yields
• Used relative perennial wheat straw yield (1.61) to calculate
straw yields
• Perennial wheat grain and straw yield was assumed to
decrease 30% per year (rough estimate of stand thinnng)
• Wheat price =$4.70/bu
• Straw price= $0.07/lb
• All values are on a per acre basis
Soft red winter wheat: Conventional vs. No-till Cost Conv No-Till
Seed 72.80 72.80
N 71.65 71.65
P 27.05 27.05
K 13.35 13.35
Herb 8.00 8.00
FHB 16.40 16.40
Leaf 10.50 10.50
Fuel 15.70 7.40
Repairs 15.55 12.45
Crop in 10.30 10.30
marketing 1.85 1.85
Cust fert 9.85 9.85
cust pest 19.70 19.70
Trucking 16.85 16.85
labour 13.70 5.95
interest 9.95 9.35
Total 333.20 313.45
Cost Conv No-Till
Straw P 2.45 2.45
K 13.90 13.90
Fuel 2.95 2.95
repairs 3.25 3.25
twine 2.95 2.95
other 12.70 12.70
Overhead depreciation 33.30 21.90
interest 16.95 12.30
other 12.75 8.10
Total 101.20 80.50
Revenue Conv No-Till
Grain yield 80.00 80.00
(bu/ac) price 4.70 4.70
straw yield 2513 2513
(lbs/ac) price 0.07 0.07
Total 551.91 551.91
Net Income: $/ac
Conv No-Till
117.51 157.96
Economics (If all things equal!)Annual Perennial Wheat
Cost no-till Year1 Year 2 Year 3
Seed 72.80 72.80 0.00 0.00
N 71.65 71.65 71.65 71.65
P 27.05 27.05 27.05 27.05
K 13.35 13.35 13.35 13.35
Herb 8.00 8.00 8.00 8.00
FHB 16.40 16.40 16.40 16.40
Leaf 10.50 10.50 10.50 10.50
Fuel 7.40 7.40 4.00 4.00
Repairs 12.45 12.45 9.00 9.00
Crop in 10.30 10.30 10.30 10.30
marketing 1.85 1.85 1.85 1.85
Cust fert 9.85 9.85 9.85 9.85
cust pest 19.70 19.70 19.70 19.70
Trucking 16.85 16.85 16.85 16.85
labour 5.95 5.95 4.00 4.00
interest 9.35 9.35 9.35 9.35
Total 313.45 313.45 231.85 231.85
Annual Perennial Wheat
Cost no-till Year1 Year 2 Year 3
Straw 38.20 38.20 38.20 38.20
O/H 42.30 42.30 42.30 42.30
Total 80.50 80.50 80.50 80.50
Annual Perennial Wheat
Revenue no-till Year1 Year 2 Year 3
grain yield 80 51 36 25
price 4.70 4.70 4.70 4.70
straw yield 2513 4045 2832 1982
price 0.07 0.07 0.07 0.07
Total 551.91 523.86 366.70 256.69
Annual Perennial Wheat
no-till Year1 Year 2 Year 3
Net Income 157.96 129.91 54.35 -55.66
But, what if…
• Is harvesting straw from your wheat crop sustainable long
term?
– Annuals=loss of organic matter and nutrients
– Perennials=living plant remains, anchoring soil, some maintenance of
nutrients
Annual Perennial Wheat
no-till Year1 Year 2 Year 3
Seed 313.45 313.45 231.85 231.85
Straw 0 38.20 38.20 38.20
O/H 42.30 42.30 42.30 42.30
Revenue (@4.70/bu) 376.00 523.86 366.70 256.69
Income 20.25 129.91 54.35 -55.66
But, what if…
• Is harvesting straw from your wheat crop sustainable long
term?
• Grain value for perennials is much higher
– US farmers being paid 800/ac for 20-30 bu/ac Kernza (=$26/bu)
– Or paid like organic wheat ($10/bu)
Annual Perennial Wheat
no-till Year1 Year 2 Year 3
Seed 313.45 313.45 231.85 231.85
Straw 0 38.20 38.20 38.20
O/H 42.30 42.30 42.30 42.30
Revenue ($10/bu) 376.00 795.22 556.65 389.66
Income 20.25 401.27 244.30 77.31
Environmental Benefits of Grazing of Perennial Cereals
After Grain Harvest
• Cow calf ranching is one of the
largest emitters of enteric
methane
• Recommended mitigation
strategies (From Beauchemin et al. 2011)
– Extend grain finishing
– Improved forage quality
– Change in land management
• All of these strategies relate to
perennial wheat
Mitigation of GHG’s Scenarios and Perennial Wheat
• After reproductive phase perennial cereals return to vegetative growth
– High quality pasture
– Winter grazing
• Grain marketable as food or feed after cleaning
• What’s carbon worth? = $10-50/t (could be worth $34- $294/ac)
Scenario Age of Pasture Total emissions GHG intensity % change in Soil CO2 SoilCO2
(years) (Mg CO2e) (kg CO2e/kg intensity from emissions (Mg CO2e
beef carcass) baseline (Mg CO2e) /ha/yr)
Pasture lands
Recent 1-8 -23,731.2 -94.69 -535.8 -29,176.9 2.38
Older 20-27 -11,403.0 -45.50 -309.4 -16,848.8 1.38
Other mitigation scenarios
Improved 5181.7 20.68 -4.85
forage quality
Extending grain 5277.2 21.35 -1.76
finishing
From Beauchemin et al. 2011
Conclusions from Economic Analysis
• Perennial wheat can be competitive to annual wheat if
straw is considered
• If a price premium (>$9.62) exists for perennial wheat
then it become economically viable
• If carbon sequestration is considered that could change
the economics as well
• Further efforts into examining economic benefits to
livestock producers from grazing perennial wheat in the
spring and fall is required
PERENNIAL WHEAT PRODUCTION
SYSTEM
What Would a Perennial Grain System Look
Like?
• Monoculture vs. polyculture
• Livestock focused vs. grain production system
• Natural vs. intensive management
The truth is we don’t know!
• Major factors include
– Life span of the perennial plant
– Complimentary species in polyculture
– Environmental conditions (moisture, length of season)
Polyculture and Mixtures
Bell, 2013
Phase cropping
Bell, 2013
Biggest fears!• Wheat on wheat on wheat
• Disease!
• Insect and virus resistance is
critical
– Mites
– Aphids
• Wheatgrass is a source of
disease and pest resistance for
wheat
• Further research is required
– Cereal entomology
– Cereal pathology
Photo by Jeanne Falk Jones
Photo by DAFWA © 2013,
Photo by Amer. Pth. Soc/.
Other methods to counter these issues
Varietal Blends
• Example in barley for Ontario
• Can increase yield
• Can provide yield stability
• Blends are used to preserve
orange wheat blossom midge
resistance in spring wheat
• Blends considered to preserve
disease resistance traits in
multiple cereal species
What are the Social Benefits of Perennial
Cereals?
• Reduction in farm labour and stress
– Seeding is spread out…over years!
– Think of perennial grains like fall seeded grains
– Reduced handling and application of pesticides
– More access to soil water and increase soil organic carbon
means production stability for farms
– Gains in efficiency
• Benefits to civilization
– It’s food, people eat it in many forms
– Many linked to environmental improvements
– Stable cost effective food production
DEVELOPMENT OF PERENNIAL
WHEAT
Problems with Perennial Wheat
• Major issues with genomic stability– Lose chromosomes
randomly
– Bits and pieces of chromosomes broken off or added
• Major issues with seed set
• Major issues with perennial growth habit
• 90 years of work by breeders and there isn’t anything viable!
0102030405060708090
Per
cen
t F
erti
lity
of
Sp
ikes
Perennial Wheat Line
TFL1
FDL2
+
TFL1
Juvenile
Phase
PPD1
CO2
VRN3
(FT)
FDL2
+
VRN3
Vegetative Phase
Secondary induction Primary induction
Long daysShort days
Long days
vernalizationVRN1
VRN2
Before
vernalization
Aftervernalization
TFL vs VRN3FDL2
CO2 vs. VRN2NF-Y
Flowering
Reproductive
Phase
Winter
(short day)
Spring/Summer
(long day)
Fall
(short day)
upregulation of
VRN3 (+ve
feedback loop
with VRN1)
induces
flowering
upregulation of
TFL1 at the
crown regulates
vegetative
growth
mR
NA
exp
ressio
n
VRN3 mRNA
TFL1 mRNA
VRN2 mRNA
VRN2
Expression
starts to get
downregulate
d
Figure 1a: A flowering pathway model based on earlier studies
in Arabidopsis, wheat and perennial plants
Figure 1b: A simplified hypothetical model for
expression pattern of three key flowering time genes
(VRN2, VRN3, TFL1) in perennial wheatgrass
requiring vernalization. The cartoon represents one
complete growth cycle.
VRN1 mRNA
PPD1 mRNA
Wheatgrass Flowering Gene Sequence
Similarity in Comparison to Wheat
Take home message: They are similar!
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Developmental stages
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How Can We Use This Information• What about a GMO?
– Main problem is that it appears that
the annual habit genes dominate
over the perennial genes
– Probably requires a knockout of
annual gene and then insertion of
the new perennial gene (lots of
work)
• What about this gene editing thingy
(ZFN, TALEN & CRISPR)?
– A new technology with limited
research in introducing new
sequence over old sequence
– Seems like the best approach based
on what we know
Summary
• Perennial wheat has real benefits from a sustainability
perspective (environmental, economic and social)
• Grain yields are lower than annual wheat
• Biomass yields are higher than annual wheat providing
marketing avenues for straw and livestock grazing
• Perennial wheat can be economical viable in comparison to
annual wheat based on marketing of straw and price premiums
• Production system will provide novel benefits and will challenge
us to develop new methods of cropping
• Perennial wheat breeding is a long term endeavour which will
require all possible tools to reach the end goal50
Thank you!
For more information, please contact:
@jamie_larsen