Abstract
Knowledge of population size is an important step for identifying populations of immediate conservation concern. However, this task is difficult in plant species that exhibit clonal growth, since a simple “head count” may not be appropriate. Here, I determine the genetic population size and the extent of clonality in the four known populations of a rare sunflower, Helianthus verticillatus. Previous work in this species revealed high genetic diversity in all populations but significant fitness differences among them. In this study, populations exhibited high clonal diversity but consisted of far fewer genetic individuals than previously reported. Moreover, the clonal structure of populations was clumped, such that genotypes were highly clustered, which may promote selfing among genets. The results of this study are related to previously examined levels of genetic diversity and fitness, and findings are discussed in the context of the ecological and biological dynamics in clonal plant populations. Finally, the results of this study led to an upgrade in the priority status of this species for the Endangered Species List.
References
Ainsworth EA, Tranel PJ, Drake BG, Long SP (2003) The clonal structure of Quercus geminata revealed by conserved microsatellite loci. Mol Ecol 12:527–532
Allison JR (2002) Survey for Helianthus verticillatus Small in Georgia. Unpublished report of the U.S. Fish and Wildlife Service, Jackson, MS. 2 pp + appendices
Brzosko E, Wroblewska A, Ratkiewicz M (2002) Spatial genetic structure and clonal diversity of island populations of lady’s slipper (Cypripedium calceolus) from the Biebrza National Park (northeast Poland). Mol Ecol 11:2499–2509
Charlesworth D, Charlesworth B (1987) Inbreeding depression and its evolutionary consequences. Annu Rev Ecol Evol S 18:237–268
Charpentier A, Grillas P, Thompson JD (2000) The effects of population size limitation on fecundity in mosaic populations of the clonal macrophyte Scirpus maritimus (Cyperaceae). Am J Bot 87:502–507
Cook RE (1983) Clonal plant populations. Am Sci 71:244–253
Doyle JJ, Doyle JL (1987) A rapid DNA isolation procedure for small amounts of fresh leaf tissue. Phytochem Bull 19:11–15
Ellis JR (2008) Conservation genetics of the endangered sunflower Helianthus verticillatus. Doctoral dissertation, Vanderbilt University
Ellis JR, Burke JM (2007) EST-SSRs as a resource for population genetic analyses. Short review. Heredity 99:125–132
Ellis JR, McCauley DE (2009) Phenotypic differentiation in fitness related traits between populations of an extremely rare sunflower: conservation management of isolated populations. Biol Conserv 142:1836–1843
Ellis JR, Pashley CH, Burke JM, McCauley DE (2006) High genetic diversity in a rare and endangered sunflower as compared to a common congener. Mol Ecol 15:2345–2355
Ellstrand NC, Roose ML (1987) Patterns of genotypic diversity in clonal plants. Am J Bot 74:123–131
Erickson O, Jerling L (1990) Hierarchical selection and risk spreading in clonal plants. In: van Groenendael J, de Kroon H (eds) Clonal growth in plants: regulation and function. SPB Academic Publishing, The Hague, The Netherlands, pp 79–94
Esselman EJ, Jianqiang L, Crawford DJ, Windus L, Wolfe AD (1999) Clonal diversity in the rare Calamagrostis porteri ssp. insperata (Poaceae): comparative results for allozymes and random amplified polymorphic DNA (RAPD) and intersimple sequence repeat (ISSR) markers. Mol Ecol 8:443–451
Fager EW (1972) Diversity—Sampling Study. Am Nat 106:293–310
Handel SN (1985) The intrusion of clonal growth—patterns on plant breeding systems. Am Nat 125:367–384
Harper JL (1985) Modules, branches, and the capture of resources. In: Jackson JBC, Buss LW, Cook RE (eds) Population biology and evolution of clonal organisms. Yale University Press, New Haven, CT, pp 1–33
Honnay O, Jacquemyn H (2008) A meta-analysis of the relation between mating system, growth form and genotypic diversity in clonal plant species. Evol Ecol 22:299–312
Leimu R, Mutikainen P, Koricheva J, Fischer M (2006) How general are the positive relationships between plant population size, fitness and genetic variation? J Ecol 94:942–952
Matthews JF, Allison JR, Ware RT Sr, Nordman C (2002) Helianthus verticillatus Small (Asteraceae) rediscovered and redescribed. Castanea 67:13–24
Murawski DA, Hamrick JL (1990) Local genetic and clonal structure in the tropical terrestrial bromeliad, Aechmea magdalenae. Am J Bot 77:1201–1208
Newman D, Pilson D (1997) Increased probability of extinction due to decreased genetic effective population size, experimental populations of Clarkia pulchella. Evolution 51:354–362
Parks JC, Werth CR (1993) A study of spatial features of clones in a population of bracken fern, Pteridium aquilinum (Dennstaedtiaceae). Am J Bot 80:537–544
Pashley CH, Ellis JR, McCauley DE, Burke JM (2006) EST databases as a source for molecular markers: lessons from Helianthus. J Hered 97:381–388
Pielou EC (1969) An Introduction to mathematical ecology. Wiley-Interscience, New York
Primack RB (2002) Essentials of Conservation Biology, 3rd edn. SinauerAssociates, Massachusetts
Rossetto M, Gross CL, Jones R, Hunter J (2004) The impact of clonality on an endangered tree (Elaeocarpus williamsianus) in a fragmented rainforest. Biol Conserv 117:33–39
Schuelke M (2000) An economic method for the fluorescent labeling of PCR fragments. Nat Biotechnol 18:233–234
Sipes SD, Wolf PG (1997) Clonal structure and patterns of allozyme diversity in the rare endemic Cycladenia humilis var. jonesii (Apocynaceae). Am J Bot 84:401–409
Sydes MA, Peakall R (1998) Extensive clonality in the endangered shrub Haloragodendron lucasii (Haloragaceae) revealed by allozymes and RAPDs. Mol Ecol 7:87–93
Wills DM, Hester ML, Liu AZ, Burke JM (2005) Chloroplast SSR polymorphisms in the Compositae and the mode of organeller inheritance in Helianthus annuus. Theor Appl Genet 110:941–947
Acknowledgments
I would like to thank Dave McCauley, Temple-Inland Corporation, Sam Breyfogle, Jim Allison, Natasha Sherman, and the Tennessee Natural Heritage Program (especially Andrea Bishop and Silas Mathes) for assistance in locating and collecting samples. I would also like to thank Vikram Chhatre for his assistance in scoring gels. This work was supported by funds provided by the Unites States Fish and Wildlife Services.
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Mandel, J.R. Clonal diversity, spatial dynamics, and small genetic population size in the rare sunflower, Helianthus verticillatus . Conserv Genet 11, 2055–2059 (2010). https://doi.org/10.1007/s10592-010-0062-3
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DOI: https://doi.org/10.1007/s10592-010-0062-3