A Systematic Evaluation of Sisyrinchium hitchcockii Matt Groberg OSU and ODA

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A Systematic Evaluation of
Sisyrinchium hitchcockii
S. hitchcockii
S. bellum
S. idahoense
Matt Groberg
OSU and ODA
Stephen Meyers, Dr. Robert Meinke
(Advisors)
Conservation Status
Organization
Status
Natural Heritage
Information Center
List 1
NatureServe
G1
Natural Heritage
Network
S2
USFWS
Species of
concern
BLM
Sensitive species
ODA
Not listed
BLM: Soggy Bottom Site
S. hitchcockii
A Brief Taxonomic History:
•
•
Hitchcock and Cronquist (1973)
group S. hitchcockii, along with
closely related species, into one
species: Sisyrinchium
angustifolium.
Henderson (1976) divided groups
of plants synonymous with S.
angustifolium into eight different
species including S. bellum, S.
idahoense, and S. hitchcockii.
– Previous taxonomic studies
based on dried plants.
– Characters in the flowers of
Sisyrinchium are not well
preserved in herbarium
specimens.
S. angustifolium
S. bellum
S. hitchcockii
S. idahoense
Henderson explains that S. hitchcockii is morphologically
unique in that it has:
Tepal
•A short creeping rhizome
•The largest flowers ( tepals up to 20 mm long)
•The widest stems and leaves ( >3mm)
Stem
Leaf
Rhizome
Definitions of a Species
• A member of a species can produce fertile
offspring with another member of that
species.
– However, plants often self fertilize or hybridize
with closely related species and produce
fertile offspring.
• A group of organisms that are
morphologically, cytologically, genetically,
and distributionally very similar.
– The species is on its own evolutionary track.
Speciation
• Allopatric Speciation: new species are formed
when a geographic or ecological barrier between
two populations prevents gene flow over a long
period of time.
• Sympatric Speciation: new species are
formed when internal barriers, such as
polyploidy, reduce or prevent gene flow between
the new species and the preserved species.
Polyploidy
Distribution
S. hitchcockii
S. bellum
S. idahoense
Chromosome Counts (Henderson
1976)
• S. hitchcockii: n = 32
• S. bellum:
n = 16
• S. idahoense: n = 32 or 48
• Suggests Polyploidy present in all three
Self Compatibility (Henderson1976)
Cross Compatibility
(Henderson1976)
Question and Hypotheses
• Q: Is S. hitchcockii a true species?
– H0: S. hitchcockii is a larger version of S.
bellum due to polyploidy, but is not genetically
unique and therefore a not true species.
– H1: S. hitchcockii is morphologically,
cytologically, and genetically unique and
therefore a true species.
Objectives
•
Compare the morphology of S. bellum and S.
idahoense to S. hitchcockii from fresh specimens and
herbarium specimens to determine if there are
differences not preserved in herbarium specimens.
Objectives
• Compare the morphology of S. bellum and S. idahoense
to S. hitchcockii from fresh specimens and herbarium
specimens to determine if there are differences not
preserved in herbarium specimens.
• Confirm that there is polyploidy in chromosome numbers
between all three species.
Objectives
• Compare the morphology of S. bellum and S. idahoense
to S. hitchcockii from fresh specimens and herbarium
specimens to determine if there are differences not
preserved in herbarium specimens.
• Confirm that there is polyploidy in chromosome numbers
between all three species.
• Analyze genetic information from all three species to
determine if S. hitchcockii is unique and to suggest a
possible phylogenetic tree.
Objectives
• Compare the morphology of S. bellum and S. idahoense
to S. hitchcockii from fresh specimens and herbarium
specimens to determine if there are differences not
preserved in herbarium specimens.
• Confirm that there is polyploidy in chromosome numbers
between all three species.
• Analyze genetic information from all three species to
determine if S. hitchcockii is unique and to suggest a
possible phylogenetic tree.
• Determine if S. hitchcockii is a true species that should
be monitored.
Objectives
• Compare the morphology of S. bellum and S. idahoense
to S. hitchcockii from fresh specimens and herbarium
specimens to determine if there are differences not
preserved in herbarium specimens.
• Confirm that there is polyploidy in chromosome numbers
between all three species.
• Analyze genetic information from all three species to
determine if S. hitchcockii is unique and to suggest a
possible phylogenetic tree.
• Determine if S. hitchcockii is a true species that should
be monitored.
• Develop a key for identification in the field.
Materials and Methods
• Morphology: key traits were measured in
each species and then statistically
compared using morphometric analysis.
Materials and Methods
• Morphology: key traits were measured in
each species and then statistically
evaluated using morphometric analysis.
• Cytology: cytometry from crushed leaves
was made with Partec GmbH ploidy
analyzer ( at OSU seed lab.)
Materials and Methods
• Morphology: key traits were measured in each
species and then statistically compared using
morphometric analysis.
• Cytology: cytometry from crushed leaves was
made with Partec GmbH ploidy analyzer ( at
OSU seed lab.)
• Genetics: DNA was extracted from the leaves.
Polymerase chain reaction (PCR) was used to
amplify nuclear non-coding DNA (nrITS) and
chloroplast DNA (matK). Phylogenetic tree was
created using Bayesian inference.
Polymerase Chain Reaction
Reason for Using Non-Coding DNA
Coding DNA
Non-Coding DNA
Results and Discussion
Morphology
Outer tepals
Fused filaments
S. hitchcockii
• Outer tepals: l:w ratio
>2.5; length usually >15mm
and up to 20mm; elliptic
and slightly wider at the top
•Yellow eye: yellow eye
small if present.
•Filaments: dark purple
and >6mm long.
S. bellum
Yellow eye
S. Idahoense
Outer tepals: l:w ratio <2.5;
length <13mm long; egg shaped,
wider at the top; topside glossy and
underside lighter than topside.
Outer tepals: l:w ratio >2.5, usually
>13mm and up to 20mm in some
varieties; oblong to slightly wider at
the top.
•Yellow eye: yellow eye robust.
•Yellow eye: yellow eye present.
•Filaments: yellow to purple and
< 6mm long.
•Filaments: yellow-tan to tan-purple
and < 6mm long.
Plot of Discriminant Functions
Function 2
4.8
species
S. bellum
S. hitchcockii
S. idahoense
Centroids
2.8
0.8
-1.2
-3.2
-7
-5
-3
-1
1
Function 1
3
5
Cytology
• Chromosome counts:
– S. hitchcockii:
– S. bellum:
– S. idahoense:
n = 32
n = 16
n = 64
Conclusion
S. hitchcockii is unique:
Conclusion
Plot of Discriminant Functions
Function 2
4.8
species
S. bellum
S. hitchcockii
S. idahoense
Centroids
2.8
0.8
-1.2
-3.2
-7
-5
-3
-1
1
Function 1
3
5
S. hitchcockii is unique:
1. Morphologically
Conclusion
Plot of Discriminant Functions
Function 2
4.8
species
S. bellum
S. hitchcockii
S. idahoense
Centroids
2.8
0.8
-1.2
-3.2
-7
-5
-3
-1
1
Function 1
3
5
S. hitchcockii is unique:
1. Morphologically
2. Cytologically
Conclusion
Plot of Discriminant Functions
Function 2
4.8
species
S. bellum
S. hitchcockii
S. idahoense
Centroids
2.8
0.8
-1.2
-3.2
-7
-5
-3
-1
1
Function 1
3
5
S. hitchcockii is unique:
1. Morphologically
2. Cytologically
3. Genetically
Acknowledgements
•
•
•
•
•
•
•
•
•
Stephen Meyers
Kelly Amsberry
OSU and UC herbaria
Dr. Robert Meinke
Rebecca Currin
Dr. Kevin Ahern & HHMI
Dr. Lynda Ciufetti
Dr. Lisa Karst
Jaworski Scholarship
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