Search results for " allozyme"
showing 7 items of 7 documents
Genetic diversity in Cytisus aeolicus Guss. (Leguminosae), a rare endemite of the Italian flora
1998
ABSTRACT Cytisus aeolicus Guss, is an endemic plant restricted to the isles of Vulcano, Stromboli and Alicudi in the Aeolian archipelago. All known populations were assayed for genetic variability using enzyme polymorphism. Allozyme variation at 16 loci coding for 10 enzyme systems was examined. The great majority of loci turned out to be monomorphic or fixed heterozygous. The observed genetic depauperation is indicative of historical factors, such as the bottleneck effect associated with migration, and the founder effect in population re-establishment. The low genetic diversity is largely partitioned within rather than among populations, indicating that extant populations have not been est…
Genetic diversity and local population structure in Ambrosina bassii (Araceae, Ambrosineae), a Mediterranean relict species
2009
The effects of habitat fragmentation on the genetic structure of Ambrosina bassii are analyzed. The species, whose reproductive biology is mostly unknown, is the only representative of its genus and tribe and it is endemic to the central Mediterranean area. The selected study area was the island of Sicily, in which wild populations show a wide morphological variability and ecological amplitude. Patterns of within- and among-population genetic diversity in eleven Sicilian populations, occurring in six disjunct areas, were examined by means of allozyme electrophoresis. High levels of genetic diversity were found as shown by the mean expected heterozygosity (He ¼ 0.263), the percentage of poly…
The Stock Genetic Structure of Two Sparidae Species, Diplodus vulgaris and Lithognathus mormyrus, in the Mediterranean Sea.
2003
Abstract Polyacrilamide gel electrophoresis (PAGE) of allozymes was used to investigate the intraspecies genetic variation and the genetic stock structure of Diplodus vulgaris and Lithognathus mormyrus captured from eight localities in the Mediterranean Sea. Twenty-two and 20 putative enzyme-coding loci were examined, respectively, in D. vulgaris and L. mormyrus . Polymorphic loci at the 95% level were used to assess the allozyme variability in D. vulgaris ( AAT-2 ∗ , EST-1 ∗ , GLDH ∗ , PEPB-2 ∗ , PGI-2 ∗ , PGM ∗ , SDH ∗ ) and L. mormyrus ( AAT-2 ∗ , EST-1 ∗ , GLDH ∗ , MDH-2 ∗ , PGI-2 ∗ , PGM ∗ ). The proportion of polymorphic loci in both species ranged from 0.31 ( D. vulgaris ) to 0.30 ( …
Congruence in genetic markers used to describe Mediterranean and Atlantic populations of European hake (Merluccius merluccius L. 1758)
2004
Summary Eight samples of the hake, Merluccius merluccius L., from the Mediterranean basin (370 fishes total) and one from the Atlantic ocean (50 fishes) were analysed in order to assess genetic variability and describe genetic population structure. Five polymorphic protein coding loci were scored (ADH*, PGI-1*, PGI-2*, PGM* and SOD-1*) in eight samples, together with a haplotype variation of four samples, obtained from polymerase chain reaction/restriction fragment length polymorphism (PCR–RFLP) analysis on the mitochondrial DNA control region. The average value for observed heterozygosity was typically higher than expected (showing an excess of heterozygotes among the samples) whereas the …
Are there any distinct genetic sub-populations of sand smelt, Atherina boyeri (Teleostei: Atherinidae) along Italian coasts? Evidence from allozyme a…
2007
Two hundred and ninety-nine specimens of Atherina boyeri, collected from five Mediterranean sites (three from the open sea (Chioggia, Catania and Gaeta) and two from river mouths (the Birgi and S. Bartolomeo rivers) were analyzed in order to confirm previous genetic studies. Eigtheen loci were scored from 12 enzymatic systems, 3 of which were polymorphic: EST*, PGM* and PGI*. Mean Fst value (0.300, p< 0.05) indicated a high genetic heterogeneity. Pairwise Fst and genetic distance revealed that samples from the river mouths (Birgi and S. Bartolomeo) were grouped separately from the open sea samples (Catania, Chioggia and Gaeta). These results are in agreement with the most recent classificat…
Artificial environmental conditions can affect allozyme genetic structure of the marine gastropod Patella caerulea
2001
Samples of the Mediterranean limpet Patella caerulea collected from 10 sites were examined for genetic population structure. Six of the 20 identified enzymatic loci were polymorphic. The AAT* locus was polymorphic only in two samples from an artificial environment (TI2 and PE). The proportion of polymorphic loci ranged from 0.20 to 0.30, and the observed and expected mean heterozygosity varied between 0.098 and 0.076 and between 0.109 and 0.086, respectively. Mean Fis values were significantly positive in AAT*, ESTD*, PEPC-2*, and PEPD*, showing heterozygosity deficiency. In all, mean Fst value of 0.007 indicated high genetic homogeneity between the samples analyzed, whereas single-locus Fs…
Studies on the Sicilian populations ofAnacolia webbii(Mont.) Schimp. (Bartramiaceae, Bryophyta), rare moss in Europe
2014
New data on the distribution, biology, intra- and inter-population variability and conservation state of Sicilian populations of Anacolia webbii are provided. Two new localities are reported, so that total five fragmented populations occur in the island, all of them in a rather small area in the western part of the province of Palermo. They live on wet limestone or sandstone cliffs with base at 900–1200 m a.s.l. and N, N-NE aspect, within communities of Aceri campestris-Querco-ilicis sigmetum. The plants are particularly vigorous, but some data suggest a condition of vulnerability of the populations. In fact, in addition to specificity to a rare habitat on the island, a morphometric and all…