TU Darmstadt / ULB / TUbiblio

Back from the brink: potential for genetic rescue in a critically endangered tree.

Finger, A. and Kettle, C. J. and Kaiser-Bunbury, Christopher N. and Valentin, T. and Doudee, D. and Matatiken, D. and Ghazoul, J. (2011):
Back from the brink: potential for genetic rescue in a critically endangered tree.
In: Molecular Ecology, pp. 3773-84, 20, (18), ISSN 1365-294X, [Article]

Abstract

Rare plant species are vulnerable to genetic erosion and inbreeding associated with small population size and isolation due to increasing habitat fragmentation. The degree to which these problems undermine population viability remains debated. We explore genetic and reproductive processes in the critically endangered long-lived tropical tree Medusagyne oppositifolia, an endemic to the Seychelles with a naturally patchy distribution. This species is failing to recruit in three of its four populations. We evaluate whether recruitment failure is linked to genetic problems associated with fragmentation, and if genetic rescue can mitigate such problems. Medusagyne oppositifolia comprises 90 extant trees in four populations, with only the largest (78 trees) having successful recruitment. Using 10 microsatellite loci, we demonstrated that genetic diversity is high (H(E) : 0.48-0.63; H(O) : 0.56-0.78) in three populations, with only the smallest population having relatively low diversity (H(E) : 0.26 and H(O) : 0.30). All populations have unique alleles, high genetic differentiation, and significant within population structure. Pollen and seed dispersal distances were mostly less than 100 m. Individuals in small populations were more related than individuals in the large population, thus inbreeding might explain recruitment failure in small populations. Indeed, inter-population pollination crosses from the large donor population to a small recipient population resulted in higher reproductive success relative to within-population crosses. Our study highlights the importance of maintaining gene flow between populations even in species that have naturally patchy distributions. We demonstrate the potential for genetic and ecological rescue to support conservation of plant species with limited gene flow.

Item Type: Article
Erschienen: 2011
Creators: Finger, A. and Kettle, C. J. and Kaiser-Bunbury, Christopher N. and Valentin, T. and Doudee, D. and Matatiken, D. and Ghazoul, J.
Title: Back from the brink: potential for genetic rescue in a critically endangered tree.
Language: English
Abstract:

Rare plant species are vulnerable to genetic erosion and inbreeding associated with small population size and isolation due to increasing habitat fragmentation. The degree to which these problems undermine population viability remains debated. We explore genetic and reproductive processes in the critically endangered long-lived tropical tree Medusagyne oppositifolia, an endemic to the Seychelles with a naturally patchy distribution. This species is failing to recruit in three of its four populations. We evaluate whether recruitment failure is linked to genetic problems associated with fragmentation, and if genetic rescue can mitigate such problems. Medusagyne oppositifolia comprises 90 extant trees in four populations, with only the largest (78 trees) having successful recruitment. Using 10 microsatellite loci, we demonstrated that genetic diversity is high (H(E) : 0.48-0.63; H(O) : 0.56-0.78) in three populations, with only the smallest population having relatively low diversity (H(E) : 0.26 and H(O) : 0.30). All populations have unique alleles, high genetic differentiation, and significant within population structure. Pollen and seed dispersal distances were mostly less than 100 m. Individuals in small populations were more related than individuals in the large population, thus inbreeding might explain recruitment failure in small populations. Indeed, inter-population pollination crosses from the large donor population to a small recipient population resulted in higher reproductive success relative to within-population crosses. Our study highlights the importance of maintaining gene flow between populations even in species that have naturally patchy distributions. We demonstrate the potential for genetic and ecological rescue to support conservation of plant species with limited gene flow.

Journal or Publication Title: Molecular Ecology
Volume: 20
Number: 18
Divisions: 10 Department of Biology
10 Department of Biology > Synthetic Ecological Networks
Date Deposited: 08 Sep 2014 10:12
Export:

Optionen (nur für Redakteure)

View Item View Item