Size-class structure and variation in seed and seedling traits in relation to population size of an endangered species Craigia yunnanensis (Tiliaceae)
Zerui Gao A B , Changqin Zhang A D and Richard I. Milne CA Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650204, China.
B The Graduate School of Chinese Academy of Sciences, Beijing 100049, China.
C Institute of Molecular Plant Sciences, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JH, UK, and Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh EH3 5 LR, UK.
D Corresponding author. Email: zhangchangqin@mail.kib.ac.cn
Australian Journal of Botany 58(3) 214-223 https://doi.org/10.1071/BT09190
Submitted: 25 October 2010 Accepted: 10 March 2010 Published: 5 May 2010
Abstract
Craigia yunnanensis W. W. Sm. & W. E. Evans is an endangered canopy tree species distributed in southern China and northern Vietnam. We located and surveyed six remnant populations, all from subtropical areas of Yunnan, China. These six populations contained between 6 and 167 adult trees in 2007, plus larger numbers of seedlings and resprouts from cut trunks. Bulk seed samples were collected from these populations and examined for 10 fitness traits (e.g. seed number, seed length, width and 1000-seed weight, germination in the controlled light and darkness conditions and nursery, seedling height, root collar diameter and dry weight). All traits differed significantly among populations, but only number of seeds per capsule was significantly correlated with population size. For some populations, germination capacity in light was significantly higher than that in darkness, indicating that canopy removal might promote regeneration from seed. Examination of population size-class structures in four C. yunnanesis populations determined that small seedlings and resprouts are abundant, although very few of these reach even the sapling stage. Hence, the remaining populations could be expanded and conserved by allowing a proportion of seedlings and resprouts to reach maturity. However, ex situ conservation, informed by data from the present study, is also advisable in case the remaining wild populations are lost.
Acknowledgements
We are very grateful to M. Tigabu, Q. Qiao, Z.B. Huang, Y. P. Ma., C. Q. Tang, S. B. Zhang and others for their assistance with the field work and for discussion. This study was supported by the National Natural Science Foundation of China (Grant No. 30770139); the Bureau of Science and Technology of Yunnan, China (2009BB001), and the CAS Large-scale Scientific Facility (2009XXX and No. 2006BADO1806).
Busch JW
(2005) Inbreeding depression in self-incompatible and self-compatible populations of Leavenworthia alabamica. Heredity 94, 159–165.
| Crossref | GoogleScholarGoogle Scholar |
CAS |
PubMed |
[verified November 2008].
Jin JH,
Kodrul TM,
Liao WB, Wang X
(2009) A new species of Craigia from the Eocene Changchang Formation of Hainan Island, China. Review of Palaeobotany and Palynology 155, 80–82.
| Crossref | GoogleScholarGoogle Scholar |
Kearns CA,
Inouye DW, Waser NM
(1998) Endangered mutualisms: the conservation of plant–pollinator interactions. Annual Review of Ecology and Systematics 29, 83–112.
| Crossref | GoogleScholarGoogle Scholar |
Kéry M,
Matthies D, Spillmann H
(2000) Reduced fecundity and offspring performance in small populations of the declining grassland plants Primula veris and Gentiana lutea. Journal of Ecology 88, 17–30.
| Crossref | GoogleScholarGoogle Scholar |
Kolb A
(2005) Reduced reproductive success and offspring survival in fragmented populations of the forest herb Phyteuma spicatum. Journal of Ecology 93, 1226–1237.
| Crossref | GoogleScholarGoogle Scholar |
Kolb A
(2008) Habitat fragmentation reduces plant fitness by disturbing pollination and modifying response to herbivory. Biological Conservation 141, 2540–2549.
| Crossref | GoogleScholarGoogle Scholar |
Krauss SL,
Hermanutz L,
Hopper SD, Coates DJ
(2007) Population size effects on seeds and seedlings from fragmented eucalypt populations: implications for seed sourcing for ecological restoration. Australian Journal of Botany 55, 390–399.
| Crossref | GoogleScholarGoogle Scholar |
Leimu R,
Mutikainen P,
Koricheva J, Fischer M
(2006) How general are positive relationships between plant population size, fitness and genetic variation? Journal of Ecology 94, 942–952.
| Crossref | GoogleScholarGoogle Scholar |
Lesbarrères D,
Primmer CR,
Laurila A, Merilä J
(2005) Environmental and population dependency of genetic variability–fitness correlations in Rana temporaria. Molecular Ecology 14, 311–323.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Lienert J, Fischer M
(2004) Experimental inbreeding reduces seed production and germination independent of fragmentation of populations of Swertia perennis. Basic and Applied Ecology 5, 43–52.
| Crossref | GoogleScholarGoogle Scholar |
Liu HM,
Gao L,
Zheng Z, Feng ZL
(2006) The impact of Amomum villosum cultivation on seasonal rainforest in Xishuangbanna, southwest China. Biodiversity and Conservation 15, 2971–2985.
| Crossref | GoogleScholarGoogle Scholar |
Loha A,
Tigabu M, Teketay D
(2008) Variability in seed- and seedling-related traits of Millettia ferruginea, a potential agroforestry species. New Forests 36, 67–78.
| Crossref | GoogleScholarGoogle Scholar |
Loha A,
Tigabu M,
Teketay D,
Lundkvist K, Fries A
(2006) Provenance variation in seed morphometric traits, germination, and seedling growth of Cordia Africana Lam. New Forests 32, 71–86.
| Crossref | GoogleScholarGoogle Scholar |
Mamo N,
Mihretu M,
Fekadu M,
Tigabu M, Teketay D
(2006) Variation in seed and germination characteristics among Juniperus procera populations in Ethiopia. Forest Ecology and Management 225, 320–327.
| Crossref | GoogleScholarGoogle Scholar |
Mathiasen P,
Rovere AE, Premoli AC
(2007) Genetic structure and early effects of inbreeding in fragmented temperate forests of a self-incompatible tree, Embothrium coccineum. Conservation Biology 21, 232–240.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Navarro L, Guitián J
(2003) Seed germination and seedling survival of two threatened endemic species of northwest Iberian peninsula. Biological Conservation 109, 313–320.
| Crossref | GoogleScholarGoogle Scholar |
O’Brien EK,
Mazanec RA, Krauss SL
(2007) Provenance variation of ecologically important traits of forest trees: implications for restoration. Journal of Applied Ecology 44, 583–593.
| Crossref | GoogleScholarGoogle Scholar |
Reed DH
(2005) Relationship between population size and fitness. Conservation Biology 19, 563–568.
| Crossref | GoogleScholarGoogle Scholar |
Souza AF
(2007) Ecological interpretation of multiple population size structures in trees: the case of Araucaria angustifolia in South America. Austral Ecology 32, 524–533.
| Crossref | GoogleScholarGoogle Scholar |
Stewart GH, Rose AB
(1990) The significance of life history strategies in the developmental history of mixed beech (Nothofagus) forests, New Zealand. Vegetatio 87, 101–114.
| Crossref | GoogleScholarGoogle Scholar |
Vergeer P,
Rengelink R,
Copal A, Ouborg NJ
(2003) The interacting effects of genetic variation, habitat quality and population size on performance of Succisa pratensis. Journal of Ecology 91, 18–26.
| Crossref | GoogleScholarGoogle Scholar |
CAS |
Yang J,
Lovett-Doust J, Lovett-Doust L
(1999) Seed germination patterns in green dragon (Arisaema dracontium, Araceae). American Journal of Botany 86, 1160–1167.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Yang QH,
Ye WH, Yin XJ
(2007) Dormancy and germination of Areca triandra seeds. Scientia Horticulturae 113, 107–111.
| Crossref | GoogleScholarGoogle Scholar |
CAS |
Yang QH,
Wei X,
Zeng XL,
Ye WH,
Yin XJ,
Wang ZM, Jiang YS
(2008) Seed biology and germination ecophysilogy of Camellia nitidissima. Forest Ecology and Management 255, 113–118.
| Crossref | GoogleScholarGoogle Scholar |
Young A,
Boyle T, Brown T
(1996) The population genetic consequences of habitat fragmentation for plants. Trends in Ecology & Evolution 11, 413–418.
| Crossref | GoogleScholarGoogle Scholar |
