Population Comparision, Germination
Rates, and Inbreeding Depression of
Limnanthes floccosa ssp grandiflora
Julia McGonigle
Dr. Robert Meinke, Dept. Botany & Plant Pathology
Limnanthes floccosa ssp. grandiflora
State of Oregon Status
- Endangered
- Oregon Natural Heritage Information Center List 1: Taxa
threatened with extinction or presumed extinct through
its entire range
•
•
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Federal Status
- Federally endangered
without critical habitat
- Listed by FWS on
November 7, 2002 with a
recovery priority of 3C.
• 60% cis-5-eicosenoic acid
• 8% cis-5-docosenoic acid
• 10% erucic acid
Limnanthes alba
• Skin softners for the cosmetic
industry
• Biodegradable lubricants
• Inks
• Detergents
• Plasticizers
• Derivatives that can be used
as coatings, films, and
adhesives
Photo source: © 2009 Barry Breckling
http://calphotos.berkeley.edu/cgi/img_query?enlarge=0000+0000+1109+2575
Vernal Pools
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Seasonal wetlands
Annually alters
between standing
water and extreme
drying
Presence of fairy
shrimp and other
specialized species
Vernal Pool Fairy Shrimp
Branchinecta lynchi
• Germination Study
To determine the effect of 6 presoak treatments on
germination rates
• Population Comparison
4 populations were compared for reproductive
viability by measuring germination rates, flowers
per plant and number of seeds per flower
• Inbreeding Depression Study
Inbred seed was produced in an insect free
greenhouse and morphological differences in wild
collected seed and greenhouse grown inbred seed
were observed.
Presoak Treatments for
Germination Study

.2% Potassium nitrate

.2% Potassium nitrate and .05% GA

.05% GA

.25% GA

.5% GA

Water
Vleeshouwers, L. M., H. J. Bouwmeester and C. M. Karssen. “Redefining Seed Dormancy: An Attempt to
Integrate Physiology and Ecology.” Journal of Ecology, Vol. 83, No. 6 (Dec., 1995), pp. 1031-1037. Published
by: British Ecological Society
Mean Percent Germination Rates for
Presoak Treatments
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•
•
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Largest population of L. floccosa ssp.
grandiflora in Oregon
Non-native species least dense and
numerous
More native grasses surrounding the pools
No immediate threats from development or
recreational activities
Owned and maintained by Jackson County
•
Second largest population of L. floccosa ssp.
grandiflora in Oregon
•
Largest threat is non-native grasses, although
currently native species still dominate the
pools
•
Owned and maintained by The Nature
Conservancy

Invaded by non-native species

Buried gas pipeline created a series of
artificial vernal pools

Owned and maintained by Jackson County
•
Small population of L. floccosa ssp.
grandiflora
•
Vernal pools are heavily invaded by
buckbrush, which is a native species
•
Owned and maintained by The Nature
Conservancy
Mean Percent Germination Rates for
Populations of L. floccosa ssp. grandiflora
A
B
B
B
Mean # of Flowers Per Plant in
Each Population
35
30
25
A
A
AB
B
20
15
10
5
0
School
Agate
Weigh
Station
Savanna
Mean # of Seeds Per Flower in
Each Population
2
1.5
A
AB
B
B
1
0.5
0
Agate
Weigh
Station
School
Savanna
Population Conclusions
• Jackson County School
- Highest germination rate
- Larger plants
- More seeds/flower
- These trends indicate healthiest population or possibility of
inbreeding depression in other populations
•Agate Desert Preserve
- No difference in seeds/flower
- No difference in plant size
• Savanna
- Lowest germination rate
- Larger plants, but with fewer seeds/flower
• Weigh Station
- Low germination rate
- Smaller plants with fewer seeds/flower
Inbreeding Depression
The loss of fitness and/or fecundity due to increased
homozygosity
Why important for Vernal Pool species?
• Small isolated islands aid in decreased gene flow among
populations
• May reduce the overall genetic variability in population
• Many vernal pool species currently threatened or endangered
due to habitat loss
• Makes the results of severe population reducing events (such as
bottlenecks) more extreme
Inbreeding Depression Study

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
Germinate 200 wild collected seeds from Agate,
School, and Weigh Station populations and 150
from Savanna population
Assess breeding system via manual outcrossing
Bag the plants to be inbred at budding stage to
ensure self pollination
Collect f1 seed, germinate and grow to seed
Examine morphological differences in plants
grown from f1 seed and plants grown from wild
seed in each of the 4 populations
Seed Weight (mg)
Inbred Seed Weight vrs
Outcrossed Seed Weight
10
9
8
7
6
5
4
3
2
1
0
A
B
Outcrossed
Inbred
Number of Seeds Per Flower
2.0
A
1.5
A
1.0
0.5
0.0
Outcrossed
Inbred
Acknowledgements
•
Oregon Department of Agriculture Native Plant
Conservation Program
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Dr. Robert Meinke
Dr. Stephen Meyers
Rebecca Currin
Kelly Amsberry
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Howard Hughes Medical Institute
•
The Ernest and Pauline Jaworski Fund