Australian Flora Foundation

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Australian Flora Foundation FINAL REPORT Life
histories and reproductive strategies of
halophytic plants suitability of Frankenia
(Frankeniaceae) for revegetation in
Australia. Prepared by Dr Lyndlee C.
Easton School of Biological Sciences Flinders
University GPO Box 2100, Adelaide 5001 25th June
2008
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• Project summary
• This PhD project provided information on the life
  histories and reproductive strategies of
  Australian plant species in the genus Frankenia.
• Global distribution
• Mediterranean coastal, and arid inland regions
• Specialised soil types e.g. saline and gypseous
  soils
• Australia has the greatest number of species of
  Frankenia

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• Project summary
• Small shrubs, sub-shrubs or herbs,
• Habitats coastal cliffs, sand dunes, coastal
  salt marshes, margins of salt lakes and salt
  pans.

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• Project summary
• Frankenia were investigated because they occur
  naturally in harsh environments
• (1) Use in revegetation projects - coastal zones
  or salt affected regions
• (2) Plant cultivation - tolerance to saline and
  drought conditions.

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• Project summary
• This project provided key data on interspecific
  variation in reproductive strategies
• Variation in seed mass/number per fruit
• Significance on germination success under
  different environmental conditions
• Ambient temperature
• Salinity levels
• Soil properties
• Seed mineral content

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• Project Aims
• Two primary aims
• To examine germination across Frankenia for seed
  age, light requirements, temperature preferences,
  salinity tolerance, and soil characteristics at
  the seed and seedling stage
• Practical significance - halophytic and saltmarsh
  plants (e.g. Frankenia) play a major role in
  reclamation programs associated with increasing
  salinity problems, and/or mine-site revegetation.
  

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• Project aims
• 2. To examine variation in seed mass and number
  among species of Frankenia to test hypotheses
  concerning the consequences of these variations
  for seedling establishment under different
  ambient conditions.
• Practical significance - produced basic
  information on the reproductive biology of
  Frankenia, including some that are of
  conservation significance
• several species have limited or disjunct
  distributions or are little known e.g. F. plicata
  is of particular conservation significance in
  South Australia

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• Project Aims
• Investigate germination requirements for
  Frankenia in relation to seed age, light
  requirements, temperature preferences, salinity
  tolerance, and soil characteristics.
• Investigate two divergent reproductive strategies
  notably seed packaging strategies in relation
  to environmental variables.
• Project Results.

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• Project Aims
• Investigate germination requirements for
  Frankenia in relation to seed age, light
  requirements, temperature preferences, salinity
  tolerance, and soil characteristics.
• Investigate two divergent reproductive strategies
  notably seed packaging strategies in relation
  to environmental variables.
• Project results
• Overall, larger-seeded Frankenia species were
  demonstrated to be advantageous for rapid
  germination after transitory water availability,
  and for providing resources to seedlings if
  resources became limiting before their successful
  establishment.

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• Project Aims
• Investigate germination requirements for
  Frankenia in relation to seed age, light
  requirements, temperature preferences, salinity
  tolerance, and soil characteristics.
• Investigate two divergent reproductive strategies
  notably seed packaging strategies in relation
  to environmental variables.
• Project results
• Overall, larger-seeded Frankenia species were
  demonstrated to be advantageous for rapid
  germination after transitory water availability,
  and for providing resources to seedlings if
  resources became limiting before their successful
  establishment.
• Smaller-seeded species delayed germination until
  both soil-water availability and cooler
  temperatures persisted over a longer time period,
  improving chances of successful establishment for
  the more slowly growing seedlings that are more
  reliant on their surroundings for resources

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The results of each facet of this project was
documented as chapters of my PhD thesis entitled
Easton, L.C. (2008) Life history strategies
of Australian species of the halophyte and arid
zone genus Frankenia L. (Frankeniaece). Flinders
University, Adelaide, Australia. Each chapter
was written as a manuscript for publication in
peer review journals. The publication status of
each manuscript is included in the manuscript
abstract.
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• For the results of salinity levels and seed mass
  on germination in Australian Frankenia species,
  please refer to manuscript A.
• Easton, L.C. Kleindorfer, S. (2009) Effects
  of salinity levels and seed mass on germination
  in Australian species of Frankenia l.
  (Frankeniaceae). Experimental and Environmental
  Botany. 65345-352.

Figure 1. Germination rates, calculated using a
modified Timson Index at Days, 2, 3, 6, and 8 at
salinity levels of 0, 10, 20, and 30.
Germination rates (a) comprises F. cinerea, F.
cordata and F. fecunda. Germination rates (b)
comprises F. foliosa, F. interioris and F.
laxiflora. Germination rates (c) comprises F.
pauciflora var. gunnii (SA varieties), F.
pauciflora var. pauciflora (WA varieties) and F.
serpyllifolia. Germination rates (d) comprises F.
sessilis, F. setosa and F. tetrapetala.
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2. For soil characteristics associated with the
habitats of central and southern Australian
Frankenia species, please refer to manuscript
B. Easton, L. C. Kleindorfer, S. (in review)
Soil characteristics associated with the habitats
of central and southern Australian Frankenia L.
species (Frankeniaceae). Plant and Soil.
Figure 3. Scatterplot generated by the first 2
Discriminant Function scores calculated to
identify soil characteristics that maximise the
differences between the 41 Frankenia populations
included in this study. Open circles represent
larger-seeded species. Closed triangles represent
smaller-seeded species. Label numbers represent
species as follows (1) F. connata, (2) F.
cordata, (3) F. eremophila, (4) F. foliosa, (5)
F. gracilis, (6) F. latior, (7) F. pauciflora
var. fruticulosa, (8) F. pauciflora var. gunnii,
(9) F. planifolia, (10) F. plicata, (11) F.
serpyllifolia, (12) F. sessilis, (13) F.
subteres.
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3. For the germination requirements for
individual Australian species of Frankenia,
please refer to manuscript C. Easton, L.C.
Kleindorfer, S. (in review) Germination
requirements for Australian species of Frankenia
L. (Frankeniaceae).
Figure 1. Germination rates for Frankenia
species, as calculated by a modified Timson
Index, by Day 8. Abbreviations are as follows
cin F. cinerea, con F. confusa, fec F.
fecunda, fol F. foliosa, lax F. laxiflora,
mag F. magnifica, p(SA) F. pauciflora var.
fruticulosa, p(WA) F. pauciflora var.
pauciflora, cor F. cordata, ere F.
eremophila, grac F. gracilis, int F.
interiores, plan F. planifolia, serp F.
serpyllifolia, ses F. sessilis, set F.
setosa, tet F. tetrapetala. Grey shading
represents smaller-seeded species. Black shading
represents larger-seeded species
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4. For seed mineral nutrient contents of
Australian species of Frankenia, please refer to
manuscript D. Easton, L.C. Kleindorfer, S.
(in prep). Seed mineral nutrient contents in
Australian species of Frankenia L.
(Frankeniaceae). Plant Sciences.
Figure 1. Scatterplot generated by the first 2
Discriminant Function scores calculated to
identify the seed mineral nutrient content
interactions that maximise the differences
between Frankenia populations included in this
study. Solid circles are larger-seeded species.
Open triangles are smaller-seeded species. Label
numbers represent species as follows (1) F.
cinerea, (2) F. cordata, (3) F. eremophila, (4)
F. fecunda, (5) F. foliosa, (6) F. glomerata, (7)
F. gracilis, (8) F. interioris, (9) F.
irregularis, (10) F. laxiflora, (11) F.
magnifica, (12) F. pauciflora var. gunnii, (13)
F. pauciflora var. pauciflora, (14) F.
planifolia, (15) F. serpyllifolia, (16) F.
sessilis, (17) F. subteres, (18) F. tetrapetala.
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5. For the results of the interaction effects of
seed mass and temperature on Australian species
of Frankenia, please refer to manuscript E.
Easton, L.C. Kleindorfer, S. (2008)
Interaction effects of seed mass and temperature
on germination in Australian species of Frankenia
L. (Frankeniaceae). Folia Geobotanica. 43 383-396
Figure 2. Partial Eta Square values for each
2-day time interval showing the proportion of the
germination rates accounted for by the
interaction of seed mass and species at 17C,
23C, and 29C.
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6. For the effects of seed mass, seed age, light
and temperature on Frankenia serpyllifolia and F.
foliosa, please refer to manuscript. Easton,
L.C. Kleindorfer, S. (2008) Germination in two
Australian species of Frankenia L., F.
serpyllifolia Lindl. and F. foliosa J.M.Black
(Frankeniaceae) effects of seed mass, seed age,
light, and temperature. Transactions of the Royal
Society of South Australia 132(1) 29-40.
Fig. 3. Germination success for F. serpyllifolia
(larger-seeded species) and F. foliosa
(smaller-seeded species) after 21 days for seed
age categories 1-, 7-, and 20-years.
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Thank you