Allozyme diversity in three endemic species of Cistus (Cistaceae) from theCanary Islands: Intraspecific and interspecific comparisons and implications for genetic conservation

Citation
F. Batista et al., Allozyme diversity in three endemic species of Cistus (Cistaceae) from theCanary Islands: Intraspecific and interspecific comparisons and implications for genetic conservation, AM J BOTANY, 88(9), 2001, pp. 1582-1592
Citations number
84
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Plant Sciences
Journal title
AMERICAN JOURNAL OF BOTANY
ISSN journal
0002-9122 → ACNP
Volume
88
Issue
9
Year of publication
2001
Pages
1582 - 1592
Database
ISI
SICI code
0002-9122(200109)88:9<1582:ADITES>2.0.ZU;2-D
Abstract
Patterns of variation at 13 isozyme loci were examined in 11 populations in three Cistus species strictly endemic to the Canary Islands. Cistus osbaec kiaefolius and C. chinamadensis display low levels of isozyme variation ass ociated with moderate to high interpopulation differentiation, which probab ly arose through historical bottlenecks in a landscape of habitat fragmenta tion, grazing, and human influence. By contrast, C. symphytifolius ranks am ong the subset of narrow endemics with high levels of isozyme variation and features different degrees of genetic structuring that are closely associa ted with taxonomic ascription. Low interpopulation differentiation in var. leucophyllus is possibly a reflection of its recent origin or of moderate l evels of gene flow between its populations. High interpopulation differenti ation in var. symphytifolius probably arose due to slight ecological differ ences between populations coupled with low levels of gene flow. Interpretat ion of neighbor-joining trees in the light of geological data substantiates the hypothesis that C. symphytifolius (or a very close relative) might be the ancestor of the other stands of Cistus in the islands. Conservation imp lications of our survey are the identification of the two populations of C. chinamadensis with the highest allele and genotype richness for preservati on on genetic grounds and advice to prevent artificial gene flow in this ta xon test it might disrupt locally adapted gene combinations. All population s of C. osbaeckiaefolius should be given conservation priority on ecologica l grounds despite their genetic depauperation.