Genecology and Seed Transfer
Guidelines for Bluebunch Wheatgrass
(Pseudorogneria spicata)
Brad St.Clair
USDA FS Pacific Northwest Research Station, Corvallis, OR
R.C. Johnson
USDA ARS Western Regional Plant Introduction Station, Pullman, WA
Nancy Shaw
USDA FS Rocky Mountain Research Station, Boise, ID
Photo: Berta Youtie
2010 Great Basin Native Plant Selection and Increase Project Annual Meeting
Objectives
1. Explore genetic variation among bluebunch
wheatgrass populations from a wide range of
source environments in the inland West
2. Relate genetic variation to environmental
variation at source locations
3. Develop seed transfer guidelines
4. Compare native variation to common cultivars
of bluebunch wheatgrass
Goal: adapted, diverse plant populations
for restoration
Methods: Population Sampling
Collections from:
127 populations
2 families per population
5 cultivars
Hanford Reserve, Central Washington
Methods: Common Garden Tests
Planted at three common garden test sites in 2006:
Central Ferry, WA – warm, dry
Lucky Peak Nursery, ID – cooler, dry
Pullman, WA – cold, wet
6 replications, 1 plant per family per rep
4,752 total plants
Transplanting Bluebunch Wheatgrass,
Lucky Peak, Fall 2006
Methods: Measurements
Eighteen traits measured in 2007 & 2008:
• Size – biomass, crown width, height, regrowth biomass
• Fecundity – inflorescence number
• Phenology – heading, anthesis, seed maturation, germination
• Morphology – plant form, leaf width, leaf length, leaf color,
leaf pubescence, culm length, spike length, spikelet number,
awn length
Analyses
• ANOVA
– Differences among test sites and between years
– Population and family component of variances
– Interactions: genotype x site and genotype x year
• Also evaluated by correlations among test sites and between years
• Correlations among traits
– Individual traits
– Principal component analysis to reduce the number of traits to a
few uncorrelated traits
• Relationship of traits to environment
– Correlations
– Regressions
• Maps of genetic variation
• Evaluation of different seed zones for capturing
population differences
• Characterization of cultivars
– Mean and variances
Progress to date
• Data collection complete
– Germination tests done in 2009
• Analyses mostly done on all data
–
–
–
–
Significant differences among populations
Correlations with environment
PCA
Regressions
• Preliminary maps and guidelines
Trait means at three test sites
(average of 2007 and 2008 data)
Trait
Central Ferry
Lucky Peak
Pullman
Dry wt (g)
100
85
41
Crown width (cm)
9.5
7.5
8.4
Inflorescence no.
100
121
42
Heading date (Julian days)
133
136
143
Bloom date (Julian days)
146
150
162
Maturity date (Julian days)
184
190
199
Germination rate (Days to 50%)
5.0
6.1
4.8
Plant form (1-9 prostrate to upright)
6.1
6.3
6.5
Leaf form (ht:width ratio)
41
39
33
Leaf pubescence (1-9 none to much)
3.9
4.5
4.0
Leaf color (1-9 yellow to dark green)
3.3
3.0
2.9
Awn length (1-9 none to long)*
4.6
4.6
4.7
Size and flowering: CF > LP > PU
Phenology: CF < LP < PU
Leaf width: CF < LP < PU
* Non-significant
Trait means in 2007 compared to 2008
(average of three test sites)
Trait
2007
2008
Dry wt (g)
42
109
Crown width (cm)
5.5
11.4
Inflorescence no.
28
148
Heading date (Julian days)
133
141
Bloom date (Julian days)
148
157
Maturity date (Julian days)
189
192
Plant form (1-9 prostrate to upright)*
6.3
6.3
Leaf form (ht:width ratio)*
38
38
Leaf pubescence (1-9 none to much)
4.8
3.5
Leaf color (1-9 yellow to dark green)
3.2
2.9
Awn length (1-9 none to long)
4.6
4.7
Size and flowering: 2007<2008
Phenology: 2007 < 2008
Leaf pubescense: 2007 > 2008
Leaf color: 2007 > 2008
* Non-significant
Variation among populations and families
• Generally large levels of
population variance in 2007
% Location
Variance
Trait
CF
LP
PU
Dry wt
48
21
37
•Less so in 2008 (more “noise”
in data; e.g., crown width)
Crown width
33
23
32
Inflorescence no.
46
36
34
Heading date
37
30
19
• Low variation among families
within populations
Bloom date
22
44
27
Maturity date
17
18
10
Germination rate
19
11
7
Plant form
17
30
7
Leaf form
34
39
19
Leaf pubescence
37
28
42
Leaf color
33
35
12
Awn length
45
58
49
• No test site showed greater
population differences in all
traits
(2007 data)
Interactions of populations with test sites
Does population performance depend upon test site?
Correlations between test sites
Dry wt:
CF w/ LP
CF w/ PU
LP w/ PU
Heading date:
CF w/ LP
CF w/ PU
LP w/ PU
Leaf ratio:
CF w/ LP
CF w/ PU
LP w/ PU
Crown width:
CF w/ LP
CF w/ PU
LP w/ PU
2007
0.83
0.77
0.79
2008
0.80
0.75
0.81
0.83
0.68
0.66
0.50
0.38
0.55
0.85
0.84
0.85
0.85
0.81
0.85
0.83
0.78
0.74
-0.28
0.14
-0.12
Answer: No. In general, little GxE
(Test Site)
- Few significant interactions
- Traits are strongly correlated among
sites
- A few traits not correlated among
sites in 2008 (crown width, culm length)
Interactions of populations with years
Does population performance depend upon year of evaluation?
Correlations between years
Dry wt:
CF
LP
PU
Heading date:
CF
LP
PU
Leaf ratio:
CF
LP
PU
Crown width:
CF
LP
PU
r
0.77
0.75
0.88
0.66
0.59
0.42
0.81
0.84
0.80
0.02
-0.05
0.10
Answer: No. In general, little GxYear
- Few significant interactions
- Traits are mostly strongly correlated
among years
- A few traits not correlated between
years (crown width, regrowth)
Correlations among traits
Correlations among size traits:
Dry wt w/ crown width (2007) 0.86
Dry wt w/ inflorescence no.
0.77
Dry wt w/ height
0.39
Correlations among phenology traits:
Heading w/ anthesis
0.73
Heading w/ maturation
0.34
Anthesis w/ maturation
0.51
Other traits not strongly correlated
Correlations between other traits:
Dry wt w/ heading
-0.12
Heading w/ leaf ratio
-0.15
Heading w/ leaf color
0.08
Some traits are correlated.
Other traits appear to be
independent of each other.
Suggests that PCs may be
easily interpretable.
Correlations of first five principal components with individual traits
Trait
PC1
PC2
PC3
PC4
PC5
Dry wt
0.87
-0.09
0.04
-0.09
-0.09
Inflorescence no.
0.76
-0.23
0.11
-0.20
0.05
Plant form
-0.50
-0.09
0.06
0.20
-0.16
Leaf color
0.57
0.14
-0.20
-0.02
0.18
Heading date
0.01
0.71
0.09
0.24
0.29
Bloom date
-0.11
0.62
0.33
0.19
0.13
Maturity date
0.00
0.32
0.15
0.03
-0.03
Leaf form
-0.26
-0.32
0.68
0.23
0.07
Awn length
0.18
0.27
-0.55
0.67
-0.31
Leaf pubescence
-0.33
-0.30
0.08
0.02
0.61
Germination rate
-0.18
-0.03
0.08
-0.04
-0.11
Percent of trait
variation in PC
23%
10%
7%
7%
5%
PC1 = greater vigor, size, fecundity, more prostrate, greener
PC2 = later phenology
PC3 = narrower leaves, shorter awns
PC4 = longer awns
PC5= fuzzier leaves
Correlations of traits with climate
(Individual traits are average correlations across years and test sites)
Trait
Annual
Precip
Aug
Precip
Annual
Temp
Aug
Max
Temp
Dec
Min
Temp
Frost
Free
Period
Latitude
Elevation
PC1
0.38
0.40
-0.06
-0.21
0.26
-0.05
0.35
-0.18
PC2
0.28
0.21
-0.38
-0.25
-0.36
-0.44
-0.41
0.49
More vigorous from
wetter, cooler summers,
warmer winters
Later phenology from
colder areas
PC3
-0.31
-0.34
0.39
0.50
0.18
0.22
0.08
-0.32
Narrow leaves from
drier, warmer summers
PC4
-0.07
-0.20
0.07
0.09
0.08
-0.22
-0.33
0.10
Longer awns from
cooler areas
PC5
-0.16
-0.10
-0.05
-0.10
0.00
-0.06
0.07
0.12
Not strongly related to
climate
Dry wt
0.35
0.33
0.04
-0.12
0.32
0.03
0.37
-0.26
Larger from
wetter, warmer winters
Inflorescence
no.
0.19
0.22
0.10
-0.05
0.34
0.10
0.43
-0.32
More flowers from
wetter, warmer winters
Plant form
-0.32
-0.31
0.05
0.17
-0.17
0.00
-0.31
0.14
More prostrate from
wetter areas
Leaf color
0.27
0.22
-0.14
-0.24
0.11
-0.11
0.14
0.04
Greener from
wetter, warmer summers
Heading date
0.10
0.07
-0.28
-0.19
-0.23
-0.36
-0.29
0.36
Later phenology from
colder areas
Leaf form
-0.44
-0.47
0.47
0.51
0.27
0.27
0.09
-0.37
Narrow leaves from
drier, warmer summers
Awn length
0.26
0.22
-0.23
-0.29
-0.02
-0.31
-0.19
0.21
Longer awns from
cooler areas
Leaf
pubescence
-0.33
-0.31
0.16
0.14
0.08
0.12
0.01
-0.01
Fuzzier leaves from
drier areas
Correlations of traits with climate
(Individual traits are average correlations across years and test sites)
Trait
Annual
Precip
Aug
Precip
Annual
Temp
Aug
Max
Temp
Dec
Min
Temp
Frost
Free
Period
Latitude
Elevation
PC1
0.38
0.40
-0.06
-0.21
0.26
-0.05
0.35
-0.18
PC2
0.28
0.21
-0.38
-0.25
-0.36
-0.44
-0.41
0.49
More vigorous from
wetter, cooler summers,
warmer winters
Later phenology from
colder areas
PC3
-0.31
-0.34
0.39
0.50
0.18
0.22
0.08
-0.32
Narrow leaves from
drier, warmer summers
PC4
-0.07
-0.20
0.07
0.09
0.08
-0.22
-0.33
0.10
Longer awns from
cooler areas
PC5
-0.16
-0.10
-0.05
-0.10
0.00
-0.06
0.07
0.12
Not strongly related to
climate
Dry wt
0.35
0.33
0.04
-0.12
0.32
0.03
0.37
-0.26
Larger from
wetter, warmer winters
Inflorescence
no.
0.19
0.22
0.10
-0.05
0.34
0.10
0.43
-0.32
More flowers from
wetter, warmer winters
Plant form
-0.32
-0.31
0.05
0.17
-0.17
0.00
-0.31
0.14
More prostrate from
wetter areas
Leaf color
0.27
0.22
-0.14
-0.24
0.11
-0.11
0.14
0.04
Greener from
wetter, warmer summers
Heading date
0.10
0.07
-0.28
-0.19
-0.23
-0.36
-0.29
0.36
Later phenology from
colder areas
Leaf form
-0.44
-0.47
0.47
0.51
0.27
0.27
0.09
-0.37
Narrow leaves from
drier, warmer summers
Awn length
0.26
0.22
-0.23
-0.29
-0.02
-0.31
-0.19
0.21
Longer awns from
cooler areas
Leaf
pubescence
-0.33
-0.31
0.16
0.14
0.08
0.12
0.01
-0.01
Fuzzier leaves from
drier areas
Correlations of traits with climate
(Individual traits are average correlations across years and test sites)
Trait
Annual
Precip
Aug
Precip
Annual
Temp
Aug
Max
Temp
Dec
Min
Temp
Frost
Free
Period
Latitude
Elevation
PC1
0.38
0.40
-0.06
-0.21
0.26
-0.05
0.35
-0.18
PC2
0.28
0.21
-0.38
-0.25
-0.36
-0.44
-0.41
0.49
More vigorous from
wetter, cooler summers,
warmer winters
Later phenology from
colder areas
PC3
-0.31
-0.34
0.39
0.50
0.18
0.22
0.08
-0.32
Narrow leaves from
drier, warmer summers
PC4
-0.07
-0.20
0.07
0.09
0.08
-0.22
-0.33
0.10
Longer awns from
cooler areas
PC5
-0.16
-0.10
-0.05
-0.10
0.00
-0.06
0.07
0.12
Not strongly related to
climate
Dry wt
0.35
0.33
0.04
-0.12
0.32
0.03
0.37
-0.26
Larger from
wetter, warmer winters
Inflorescence
no.
0.19
0.22
0.10
-0.05
0.34
0.10
0.43
-0.32
More flowers from
wetter, warmer winters
Plant form
-0.32
-0.31
0.05
0.17
-0.17
0.00
-0.31
0.14
More prostrate from
wetter areas
Leaf color
0.27
0.22
-0.14
-0.24
0.11
-0.11
0.14
0.04
Greener from
wetter, warmer summers
Heading date
0.10
0.07
-0.28
-0.19
-0.23
-0.36
-0.29
0.36
Later phenology from
colder areas
Leaf form
-0.44
-0.47
0.47
0.51
0.27
0.27
0.09
-0.37
Narrow leaves from
drier, warmer summers
Awn length
0.26
0.22
-0.23
-0.29
-0.02
-0.31
-0.19
0.21
Longer awns from
cooler areas
Leaf
pubescence
-0.33
-0.31
0.16
0.14
0.08
0.12
0.01
-0.01
Fuzzier leaves from
drier areas
Correlations of traits with climate
(Individual traits are average correlations across years and test sites)
Trait
Annual
Precip
Aug
Precip
Annual
Temp
Aug
Max
Temp
Dec
Min
Temp
Frost
Free
Period
Latitude
Elevation
PC1
0.38
0.40
-0.06
-0.21
0.26
-0.05
0.35
-0.18
PC2
0.28
0.21
-0.38
-0.25
-0.36
-0.44
-0.41
0.49
More vigorous from
wetter, cooler summers,
warmer winters
Later phenology from
colder areas
PC3
-0.31
-0.34
0.39
0.50
0.18
0.22
0.08
-0.32
Narrow leaves from
drier, warmer summers
PC4
-0.07
-0.20
0.07
0.09
0.08
-0.22
-0.33
0.10
Longer awns from
cooler areas
PC5
-0.16
-0.10
-0.05
-0.10
0.00
-0.06
0.07
0.12
Not strongly related to
climate
Dry wt
0.35
0.33
0.04
-0.12
0.32
0.03
0.37
-0.26
Larger from
wetter, warmer winters
Inflorescence
no.
0.19
0.22
0.10
-0.05
0.34
0.10
0.43
-0.32
More flowers from
wetter, warmer winters
Plant form
-0.32
-0.31
0.05
0.17
-0.17
0.00
-0.31
0.14
More prostrate from
wetter areas
Leaf color
0.27
0.22
-0.14
-0.24
0.11
-0.11
0.14
0.04
Greener from
wetter, warmer summers
Heading date
0.10
0.07
-0.28
-0.19
-0.23
-0.36
-0.29
0.36
Later phenology from
colder areas
Leaf form
-0.44
-0.47
0.47
0.51
0.27
0.27
0.09
-0.37
Narrow leaves from
drier, warmer summers
Awn length
0.26
0.22
-0.23
-0.29
-0.02
-0.31
-0.19
0.21
Longer awns from
cooler areas
Leaf
pubescence
-0.33
-0.31
0.16
0.14
0.08
0.12
0.01
-0.01
Fuzzier leaves from
drier areas
Correlations of traits with climate
(Individual traits are average correlations across years and test sites)
Trait
Annual
Precip
Aug
Precip
Annual
Temp
Aug
Max
Temp
Dec
Min
Temp
Frost
Free
Period
Latitude
Elevation
PC1
0.38
0.40
-0.06
-0.21
0.26
-0.05
0.35
-0.18
PC2
0.28
0.21
-0.38
-0.25
-0.36
-0.44
-0.41
0.49
More vigorous from
wetter, cooler summers,
warmer winters
Later phenology from
colder areas
PC3
-0.31
-0.34
0.39
0.50
0.18
0.22
0.08
-0.32
Narrow leaves from
drier, warmer summers
PC4
-0.07
-0.20
0.07
0.09
0.08
-0.22
-0.33
0.10
Longer awns from
cooler areas
PC5
-0.16
-0.10
-0.05
-0.10
0.00
-0.06
0.07
0.12
Not strongly related to
climate
Dry wt
0.35
0.33
0.04
-0.12
0.32
0.03
0.37
-0.26
Larger from
wetter, warmer winters
Inflorescence
no.
0.19
0.22
0.10
-0.05
0.34
0.10
0.43
-0.32
More flowers from
wetter, warmer winters
Plant form
-0.32
-0.31
0.05
0.17
-0.17
0.00
-0.31
0.14
More prostrate from
wetter areas
Leaf color
0.27
0.22
-0.14
-0.24
0.11
-0.11
0.14
0.04
Greener from
wetter, warmer summers
Heading date
0.10
0.07
-0.28
-0.19
-0.23
-0.36
-0.29
0.36
Later phenology from
colder areas
Leaf form
-0.44
-0.47
0.47
0.51
0.27
0.27
0.09
-0.37
Narrow leaves from
drier, warmer summers
Awn length
0.26
0.22
-0.23
-0.29
-0.02
-0.31
-0.19
0.21
Longer awns from
cooler areas
Leaf
pubescence
-0.33
-0.31
0.16
0.14
0.08
0.12
0.01
-0.01
Fuzzier leaves from
drier areas
Amount of variation accounted for by regression
of trait on climate and geography
R2 from
regression
% Variation
in PC
PC1
0.53
0.23
PC2
0.43
0.10
PC3
0.37
0.07
PC4
0.45
0.07
PC5
0.14
0.05
Dry wt
0.54
--
Heading date
0.48
--
Leaf form
0.43
--
Awn length
0.40
--
Leaf
pubescence
0.43
--
Trait
(Regressions using individual traits are for
traits measured in 2007 at Central Ferry)
• Large population variation
• Moderately strong
relationships between traits and
climate
• Relationships make sense
Suggests adaptively
significant variation that
should be considered in
moving populations
Maps of genetic variation in PC1 and dry weight
Red = larger, more vigorous plants,
more flowers, more prostrate
Blue = smaller, less vigorous plants,
fewer flowers, less prostrate
Red = larger plants
Blue = smaller plants
Some differentiation between level 3 ecoregions, but clines within
W  E within Blue Mtns, Great Basin
S  N within Columbia Basin
Maps of genetic variation in PC2 and heading date
Red = later phenology
Blue = earlier phenology
Red = latter phenology
Blue = earlier phenology
Differentiation between level 3 ecoregions
Low  high elevation within mountainous ecoregions
W vs E in northern Nevada
Maps of genetic variation in PC3 and leaf form
Red = narrow leaves, shorter awns
Blue = wider leaves, longer awns
Red = narrow leaves
Blue = wider leaves
Differentiation between level 3 ecoregions, but clinal variation within
associated ecoregions associated with precipitation.
W vs E in northern Nevada
Maps of genetic variation in first three PCs
Preliminary population movement guidelines:
• Stay largely within level 3 ecoregions
• Within ecoregions, likely to be 2-4 zones
associated with clines in aridity (precipitation)
and temperature (elevation)
e.g., W  E in the Blue Mountains
Conclusions
•
Large differences among test sites and between years in size and phenology
•
•
High levels of population variation in many traits
Populations means are strongly correlated among test sites and among
years, i.e., low GxE
Size traits intercorrelated; phenology traits intercorrelated; other traits
not strongly correlated with each other  principle component analysis
easily interpreted
Correlations with climate are fairly strong
Relationships make sense from an adaptation perspective
•
•
•
–
–
Size: CF>LP>PU
Phenology: CF<LP<PU
–
Larger, more vigorous plants come from populations located in wetter climates with warmer
winters but cooler summers
Plants with later heading and anthesis dates come from populations located in colder climates
Plants with narrow leaves come from populations located in areas with warmer, drier summers
Plants with more leaf pubescence come from populations located in drier climates
–
–
–
Conclusions
•
•
Thus, strong evidence for adaptively significant genetic variation
Suggests seed zones should be delineated mostly along gradients of
temperature and aridity
–
–
–
Do not move populations between level 3 ecoregions, particularly across large distances
Do not move populations across large elevation or precipitation gradients within ecoregions
Should not require a large number of seed zones
Plans for 2010
• Additional analyses to be done
–
–
–
–
Refine maps
Consider additional climate variables
Evaluation of alternative seed zones
Evaluation of cultivars
• Finalize maps and seed transfer guidelines
• Evaluate effects of climate change
• Reporting in publications and meetings