1022-7954/02/3806- $27.00 © 2002
Russian Journal of Genetics, Vol. 38, No. 6, 2002, pp. 684–690. From Genetika, Vol. 38, No. 6, 2002, pp. 820–827.
Original English Text Copyright © 2002 by Dalmazio, Cammarata, Carrillo, Calvo, Romancino, Cognetti, Di Carlo.
The marine phanerophyte
Delile is a Mediterranean paleoendemic which forms
extensive meadows on sandy bottoms of the infralit-
toral zone [1, 2] between the surface and a depth of
40 m . The distribution of the genus
widely disjunct. One species occurs in the Mediterra-
nean, whereas eight species are distributed along the
southern coasts of Australia.
ows play a multifunctional role in the coastal area of the
Mediterranean Sea [4, 5]. In particular, the
ecosystem contributes signiﬁcantly to water oxygen-
ation through photosynthetic activity (L.A.I.
gives shelter to many marine animals, provides a major
food resource for coastal and pelagic animals (either
directly through grazing or indirectly through the detri-
tus cycle), produces a large quantity of biomass towards
neighboring ecosystems, provides important nursery
and shelter beds for numerous other plant and animal
communities, helps to stabilize sandy shores and sea-
beds, through dampening effects on wave action and
subsequent sediment accumulation and molds the
coastline and protects sandy beaches from erosion.
However, despite their importance,
ows are seriously threatened in the Mediterranean Sea
today [1, 6–9]. Their location in shallow coastal waters
makes them susceptible to environmental alterations
resulting from human activities (e.g., marine coastal con-
struction, eutrophication and pollution, destructive ﬁshing
activities, pleasure boat activities, etc.).
Vegetative propagation represents the main repro-
ductive strategy for this species as opposed to sexual
reproduction (~20%) [10–12]. In the Mediterranean
Sea seedling recruitment is absent or episodic ,
principally because the species shows a low ripening
rate and a high rate of fruit loss due to the mechanism
of seed dissemination .
The dominance of vegetative propagation within
populations, coupled with a slow growth
rate, maintains low genetic diversity and might reduce
the ability of this species to respond to natural and
anthropic environmental alterations.
Recent studies on the genetic structure of
indicate that in the Mediterranean meadows it appears to
approach clonality [15–17]. The biochemical processes
that regulate the choice of one type of reproductive strat-
egy rather than the other are not known.
The use of random ampliﬁed polymorphic DNA
(RAPD) has gained widespread application because it
provides a fast, simple, and inexpensive tool for genetic
analyses . In plants utilizing anonymous and
deﬁned primers polymorphism at the population level
has been also studied [19, 20].
DNA polymorphisms in hypervariable regions are
often used to study genetic variation . These
regions consist of tandem repeats of a short sequence
called microsatellite or minisatellite which is dispersed
in the genome. The major difference between microsat-
ellite and minisatellite sequences is the size of the
Molecular Characterization of a Variable Tandem Repeat
Sequence Determined during RAPD Analysis
Insular and Coastline Populations*
, M. Cammarata
, D. Carrillo
, S. Calvo
D. P. Romancino
, G. Cognetti
, and M. Di Carlo
Istituto di Biologia dello Sviluppo CNR, via Ugo La Malfa 153, 90146 Palermo, Italy;
fax: 3991680548; e-mail: email@example.com
Dipartimento di Biologia Animale, via Archiraﬁ 18, 90123 Palermo, Italy
Dipartimento di Scienze Botaniche, via Archiraﬁ 30, 90123 Palermo, Italy
Received September 19, 2001
plays a multifunctional role in the coastal area as an important and pro-
ductive component of ecosystems in the Mediterranean Sea. We detected by RAPD analysis with two arbitrary prim-
ers genetic differences in
collected from several sites in the Southern Mediterranean. By AMOVA anal-
ysis we observed a level of about 20% genetic difference among individuals within a population and 80% among
populations. A common band of 200 bp was found in all the ampliﬁed samples. Cloning and sequencing analysis of
this band revealed the presence of a simple tandem repeat sequence (minisatellite) that we called PoTR (
tandem repeat). Finally, the ability of PoTR to detect genetic variability in
genome was dem-
onstrated by the presence of ampliﬁcation products of different lengths utilizing primers internal to this sequence.
* This article was submitted by authors in English.