Premium
RAPD variation among and within small and large populations of the rare clonal plant Ranunculus reptans (Ranunculaceae)
Author(s) -
Fischer Markus,
Husi René,
Prati Daniel,
Peintinger Markus,
Kleunen Mark,
Schmid Bernhard
Publication year - 2000
Publication title -
american journal of botany
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.218
H-Index - 151
eISSN - 1537-2197
pISSN - 0002-9122
DOI - 10.2307/2656649
Subject(s) - biology , rapd , genetic variation , ranunculus , gene flow , analysis of molecular variance , population , genetic variability , ecology , botany , zoology , genetic diversity , genetics , gene , genotype , demography , sociology
In the pre‐alpine region of Europe numbers and sizes of populations of the clonal lake shore plant Ranunculus reptans have declined because of the regulation of lake water levels. We investigated genetic variation among and within 17 populations of different size (cover 1–10 000 m 2 ) in R. reptans with RAPD (random amplified polymorphic DNA) profiles. We sampled 127 rosettes in 14 populations at Lake Constance and three populations at or near Lake Como. There was significant genetic variation between plants from the two lake regions (5.9%, analysis of molecular variance [AMOVA], P < 0.001), among populations within lake regions (20.4%, P < 0.001), and within populations (73.7%, P < 0.001). Under the assumptions of Wright's island model the variation among populations corresponds to a gene flow of N e m = 0.70. Within the 14 Lake Constance populations we detected significant genetic variation among subpopulations separated by only a few metres (4.0% of the within‐population variation; P < 0.05). Molecular variance was 24% smaller in small populations covering <100 m 2 area than in larger ones ( P < 0.03), indicating that samples from large populations were genetically more variable than samples representing comparable areas of smaller populations. We conclude that gene flow among populations is very limited and that genetic drift has caused reduced genetic variability of smaller populations. Conservation of genetic variability in R. reptans requires persistence of large and also of small populations (because of population differentiation), and it could be enhanced by increasing the size of small populations (to counter genetic drift).