Genecology of
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
2009 Great Basin Native Plant Selection and Increase Project Annual Meeting
Objectives
1.
Determine 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
Twenty traits measured in 2007 & 2008:
• Size – biomass, regrowth biomass, crown width, height
• Phenology – heading, anthesis, seed maturation, germination
• Morphology – plant form, leaf width, leaf color, leaf
pubescence, spike length, etc.
Progress to date
• Data collection nearly complete
– Germination tests ongoing
• Preliminary analysis on 2007 data
– Significant differences among populations
• Recent analyses on most data
Analyses
• ANOVA between and within sites
– Differences between test sites
– Population and family component of variances
• Genotype x site interactions
– ANOVA
– Correlations among test sites
• Correlations among traits
– Individual traits
– PCA
• 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
Trait means at three test sites
(2008 data)
Trait
Central Ferry
Lucky Peak
Pullman
Dry wt (g)
65
38
23
Crown width (cm)
6.0
5.7
4.8
Height (cm)
28
55
26
Inflorescence no.
21
52
26
Heading date (Julian days)
128
132
139
Bloom date (Julian days)
141
144
158
Maturity date (Julian days)
182
189
198
Plant form (1-9 prostrate to upright)
6.1
5.9
6.9
Leaf form (ht:width ratio)
43
36
33
Leaf color (1-9 yellow to dark green)
3.4
3.3
3.1
Leaf pubescence (1-9 none to much)
4.4
5.4
4.7
Awn length (1-9 none to long)
4.5
4.6
4.5
Size: CF > LP > PU (except height)
Phenology: CF < LP < PU
Correlations among test sites for
individual traits
Dry wt:
CF w/ LP
CF w/ PU
LP w/ PU
r
0.87
0.84
0.81
Heading date:
r
CF w/ LP
0.85
CF w/ PU
0.70
LP w/ PU
0.72
Maturation date: r
CF w/ LP
0.43
CF w/ PU
0.32
LP w/ PU
0.58
Traits are mostly strongly
correlated among sites;
i.e., not strong GxE
Variation among populations
Trait
(2008 data)
• Generally large levels of
population variance
• Low variation among families
with populations
• Source differences generally
larger at Lucky Peak and
Central Ferry
% Location
Variance
CF
LP
PU
Dry wt
49
40
28
Crown width
42
37
26
Height
11
32
15
Inflorescence no.
36
20
25
Heading date
14
35
12
Bloom date
6
11
11
Maturity date
33
55
45
Plant form
27
30
24
Leaf form
30
36
26
Leaf color
18
31
10
Leaf pubescence
35
13
37
Awn length
27
55
46
Correlations among traits
Correlations among size traits:
Dry wt w/ crown width
0.82
Dry wt w/ inflorescence no.
0.81
Dry wt w/ height
0.47
Correlations among phenology traits:
Heading w/ bloom
0.65
Heading w/ maturation
0.38
Bloom w/ maturation
0.43
Other traits not strongly correlated.
Principle component analysis:
1st PCA – a measure of size (explains 22% of variation)
2nd PCA – a measure of phenology (explains 13% of variation)
Correlations of individual traits with climate
At Lucky Peak, 2008 data
Dry Wt
Inflor
No.
Heading
Date
Bloom Mature
Date
Date
Plant
Form
Leaf
Form
Awns
Jan Temp
0.12
0.11
0.02
0.17
0.15
-0.07
0.15
0.04
Aug Temp
-0.09
-0.01
-0.19
0.07
0.13
0.07
0.28
-0.33
Spring Frost Date
-0.03
-0.07
0.25
0.09
-0.07
0.04
-0.17
0.29
Fall Frost Date
-0.03
0.04
-0.21
-0.02
0.06
0.00
0.16
-0.26
Annual Precip
0.22
0.01
0.10
-0.03
0.02
-0.23
-0.28
0.27
Aug Precip
0.22
0.05
0.08
-0.17
-0.13
-0.21
-0.23
0.27
In general, correlations with climate are not strong.
Relative to trees, no strong local adaptation.
• Larger plants are from wetter areas.
• Plants with later heading dates are from areas with later spring frost
and earlier fall frost
• Plants with upright form are from areas with less precipitation.
• Plants with narrow leaves are from hot, dry areas.
• Plants with longer awns are from areas with later spring frost, earlier
fall frosts, cooler summers, and more precipitation.
Preliminary Conclusions
• Large differences among test sites in size and phenology
– Size: CF>LP>PU
– Phenology: CF<LP<PU
• Many traits are correlated among test sites, i.e., low GxE
• High levels of populations variation in many traits
• Size traits intercorrelated; phenology traits
intercorrelated; other traits not strongly correlated
• Correlations with climate are not strong
– Not strongly adapted to local climate
– But correlations that are moderate generally make sense from an
adaptation perspective
Plans for 2009
• Germination tests ongoing
• More thorough analysis
–
–
–
–
Regressions with environment
PCA to simplify number of traits
Evaluation of alternative seed zones
Evaluation of cultivars
• Seed transfer guidelines
• Reporting in publications and meetings