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1. Introduction

The aim of this work is to bring a cytotaxonomic contribution to the knowledge of the geophytic element of the Greek flora.

The experimental part of the present research has been done in the original country of the taxonomic units investigated, in the frame of the “Socrates Project” in the Faculty of Biology of the University of Patras, Greece.

The taxa studied belongs to different families of Monocotyledons; Alliaceae,

Hyacinthaceae and Amaryllidaceae, and all are bulbous plants (geophytes), that well characterize the Mediterranen vegetation as one of the its main life forms.

Indeed the investigation here presented is placed in the wider study of the

Mediterranean flora, in which a strong collaboration between the University of Pisa and Patras is in course for many years.

The species in object come from different areas of Greece; most of them are from the Ionian Islands (Kefalonia, Lefkas and Zakynthos), and some are from Peloponnese and the Greek mainland.

Most of them are “spontaneous” in the place of picking, and only one of the species investigated, Amaryllis belladonna, belongs to the “naturalized” component of the Greek flora.

For the identificaton of the samples “Flora Hellenica ” (Strid & Tan, 1997) couldn’t be used because at present incomplete of the third volume concerning the

Monocotyledons in object.

So “Flora Europaea” have been used, and also “Flora of Turkey”, for the similarity to the Hellenic flora, in some aspect, due to the palaeogeographical history that

established connections between Greece and Anatolia. Furthermore “Flowers of

Greece and Balkans” (Polunin, 1980) was useful. Concerning a recently discovered

species, Allium ionicum Brullo & Tzanoud., it isn't present yet in any Flora, being

also a Greek endemic species with a narrow distribution only in some of the Ionian

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Islands. So it has been used for its identification the original pubblication about it (Brullo & Tzanoudakis, 1994)

It has been suitable to preceed the following short accounts about the geography,

palaeogeography, geology and climate of the Greek territory as source of the plants

studied.

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1.1 Naturalistic frame of Greece

1.2.1 Geography

Located in the Southeastern Europe, Greece forms an irregular-shaped peninsula in the Mediterranean with two additional large peninsulas projecting from it: the Chalcidice and the Peloponnese. It is the crossroad of three continents; Europe, Asia, and Africa.

It has a very long coastline, with plenty of peninsulas and islands. The mainland occupies 107,000 Kmq and the total land area including the islands is 131,957 Kmq (Strid & Tan, 1997).

The Greek Islands are generally subdivided into two groups, according to the location: the Ionian Islands (including Kerkira, Cephalonia, Lefkas, Zakinthos, Ithaky etc.) west of the mainland and the Aegean Islands (including Euboea, Samos, Chios, Lesbos, Crete etc.) to the east and south.

Greece is primarily a mountainous country, with seventy per cent of its territory covered by mountains. A large mountain range, the Hellenids (a southern branch of the Dinarids), forms the backbone of Greece. In the south of Peloponnese it disappears below sea-level and takes a sharp turn east, reappearing in the south Aegean islands arc and the three large massive of Crete; further east it continues to the Taurus range of southern Anatolia. The northern part of Hellenids is known as Pindos. In north-central and east-central Greece, two shorter interrupted ranges run more or less parallel to Pindos, one extending from Varnous to Oxia and the other from Voras to Pilio. The lower mountains of southern Sterea Hellas and the island of Evvia run in the same direction as in the main ranges. In the north-east, the pattern is more irregular, Rodopi and the smaller, more westerly Belles range extending more or less east-west, whereas another group of mountains (Orvilos to Menikio) runs roughly from north to south, forming a continuation of the Bulgarian Pirin Planina.

Other mountains in the north-east, notably Athos are more isolated. Mount Olympus,

rising to 2,917 m, is the highest point in the country, and its summit is only c. 17 Km

from the coast (Lienau, 1989). Also Peloponnese is rich of mountains; in the south

there are Párnon and Taygetos, in the centre Menalon, and in the north the relief of

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A database compiled at the Flora Hellenica secretariat and based mainly on N. K.

Nezis: Ta Ellinika Vouna (Athens 1979; see fig. 1), indicates 314 mountains and 1674 individual peaks above 1,000 m (Strid & Tan, 1997)

Large flat lowland areas, now almost entirely coltivated, are scarsely diffused in Greece; they lie around the city of Larissa (the Thessalian plain), in eastern Sterea Ellas (the Beotian plain), in north-west Peloponnese, around Messolongio and Arta, west of Thessaloniki, and in river valleys and coastal areas in the north west.

Three major rivers, the Axios, the Strimon and Nestos, flow into the north Aegean

sea; they are bordered by broad valleys, and form deltas close to the coast. The main

rivers of central Greece are the Aliakmon and Pineos flowing to east, and the

Arachtos and Acheloos to the west. In the Peloponnese the main rivers are the Alfios,

which reaches the sea near ancient Olympia in the west, and the Evrotas which flows

south into the Laconian gulf (Phitos & al., 1995).

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1.2.2 Palaeogeography

Greece belongs to the crystalline structural core of the Balkan peninsula, that was formed in the Carboniferous period (c. 360-290 million years B.P.) by masses of gneiss and marble arised from sedimentary rocks by pressure and chemical processes. The crystalline core are conspicuous in the northern and central Balkan Peninsula but only rarely exposed in the Peloponnese.

In the Cretaceous period (c. 144-65 million years B.P.) the Alpine orogenesis, gave rise to the Alps and other mountains of central and south Europe.

In Greece, the Hellenids , when originally formed, and the south Aegean island arc ran almost straight from west to east and the present curvature, developed by the expansion of the crust north of Crete, formed the Aegean sea.

After a long period of relatively geological stability when Tertiary sedimentary rocks where laid down, a third great upheaval took place in the late Tertiary and early Quaternary periods (c. 2 million years B.P.), when sedimentary rocks were lifted as high as 3000 m. Extensive fracturing and crust movement resulted in steep and jagged cliffs. These have been resist to erosion and they appearance today is virtually unchanged. They can be seen in the coastal cliff of Kithira and large parts of Taygetos range. Tertiary conglomerates and Holocene alluvial sediments lay particularly in the coastal areas of north and northwest Peloponnese, forming soft eroded landscapes (Tan & Iatrou, 2001).

Concerning the major East Aegean islands history, they have been connected to the mainland at one time or another; during the Miocene-Pliocene period, there was a South-Aegean continent, the “Kikladian land block”, connecting the Greek mainland with the west Anatolia (Creutzburg 1963). During a period of the middle Miocene, in the northern part (Central Aegean) and the southern part (Cretan area) of this Aegean continent, as well as Peloponnese, were isolated by the sea.

At the end of Miocene, during the 1,5 million year period of the Messinian

(Greuter 1979, Bertolani & Marchetti, 1984), the whole Mediterranean sea dried out

ripetively, and land connection were established again. Consequently there was

ample opportunity for estabilishment and migration of drought-resistant plant

species. The Messinian-type vegetation was at steppe and semi-desert conditions and

was displaced almost immediately by forest vegetation at the onset of Pliocene. It

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survived in specialised treeless habitat like cliffs, dunes and mountain tops, especially on the islands where it was protected against competition.

At the beginning of Pliocene, the returning sea isolated southwest Crete from the continent and from the Central Aegean area, and a little later the Central Aegean area was cut off from the western and eastern mainlands. Crete and Karpatos separated from each other and Rhodos cut off from Anatolia about 5 million years ago (Greuter,1979). During the Pleistocene, glaciation periods, regressions of the Mediterranean were common, lowering the sea level 100-200 m. As a result land connections between some central Aegean islands took place and several marginal islands became continuous with the neighbouring continents (see fig. 2). These regressions fused Crete and the Central Cyclades to each other again or to the Greek or Anatolian mainland. Therefore, these two areas apparently have remained isolated since the beginning of the Pliocene (Tzanoudakis & Vosa, 1986).

During the last glaciation (Würm) the snow line was at an altitude of c. 1600 m in the wetter mountains of northwest Greece, and during Riss glaciation was even lower, probably at c.1000 m. The southernmost indication of glaciation in Europe are found in Mount Taygetos in South Peloponnese (Tan & Iatrou, 2001).

The main palaeogeographical development of the area is reflected in the present- day plant distribuition patterns.

Kriti and Karpatos have been isolated from each other for very long period of time (about 5 million years), and have correspondingly distinctive floras. The early rift between the Kiklades and the east Aegean islands is also evident in plant distribuition pattern, as is the late connection between the east Aegean island and the Anatolian mainland.

Fig. 2 : The 200 m isobath in the central and south

Aegean (according to the bathymetric map published by

the Oceanographic Institute at Monaco). The map shows

the coast line which would result at present from a

lowering of the sea level of 200 m.

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1.2.3 Geology & phytocoenoses

Most of north-central and north-east Greece is built up of old crystalline rock. The rest of Greece, including Pindos, most of Sterea Ellas and Peloponnese, consist of younger rocks (Trias to Tertiary). Olympus and Ossa stand out in the area of older crystalline rock, being composed partly of old metamorphic limestone (marble) and partly of younger (Mesozoic) limestone (Jacobshagen, W. 1986).

Shallow calcareous soils dominate on limestone and marble throughout much of the country. They rapresent degraded soil profiles with restricted water supply.

Limestone has a poor ability to retain moisture which readily percolates cracks and crevices. As a result, limestone rocks and mountains are generally dry and may appear desolate but in fact are often of a great botanical interest, being rich in local and regional endemics. The soil will be neutral to alkaline, rich in mineral but often deficient in organic matter.

A large area of ophiolite (serpentine) occurs in northern Pindos and in scattered, smaller outcrops in north central Greece (Vourinos), Sterea Ellas, the island of Evvia and elsewhere.

Serpentine contain large amounts of magnesium and certain heavy metals such as nickel, so it’s inhospitable to many species, whereas others are particularly adapted to it as distinctive flora with several regional serpentine endemics (Kit Tan & Iatrou, 2001).

Flysch, a non calcareous Tertiary sediment, is locally prominent in north-west and central Greece and in north-northwest Peloponnese; it erodes easily forming characteristic landscape relief.

Karstic phenomena are common in the limestone areas of western and southern Greece, with several extent cave systems, dolines and poljes with fertile terra rossa soils, sometimes the only cultivated patches in an otherwise barren and rugged terrain.

Granite, gneiss and micaceous schist which occur on several of the large

mountains in northern Greece retain moinsture much more efficiently than limestone

does, and produces mountains area consequently much wetter. Schists occur also in

the Aegean area, e.g. on the islands of Andros and Tinos in the Kiklades. Fewer local

endemics are found in this areas, and the flora and vegetation is more mesic or

central European in character (Strid & Tan, 1997).

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Plate tectonics is a significant aspect of Greek geology. Greece lies on the Hellenic plate, a small crust which borders the continental African plate along the Hellenic trench southwest of Peloponnese, and the smaller Arabian plate to the south;

earthquakes and volcanic activity occur when the plates rub against each other. A tectonic zone with a string of extinct or dormant volcanoes extends from the islands of Egina (SSW of Athens) over Milos and Thira (Santorini) to Nisiros and Kos in the south-east Aegean sea. The volcanic explosion of Thira in a massive eruption around 1470 B.C. released energy several times larger that the explosion of Krakatau in 1883, and it’s believed to have contribuited to the decay of the Minoan civilization.

Volcanic substrates are scattered areas in Greece that floristically markedly differ from the adjacent regions.

1.2.4 Climate

Most of Greece has a typical Mediterranean climate with cool, wet winters and hot, dry summers although there are large regional and local differences due to the complex topography.

In the interior north, the climate is rather central European in character; rain fall throughout the year showing the maximum in the summer, whereas winter are cold and snow-rich. Anyway generally most of the precipitation are from mid-October to April with few and erratic summer rains. In general the total annual precipitation in Greece is highest in the northwest and decreases in a southeasterly direction. The annual average for Ioannina at the western flanks of Pindos is 1253 mm, and 728 mm for Patras, in the northwest Peloponnese. On the other hand, for Larissa, in the

Thessalian plain, only 451 mm and for Athens 395 mm. This difference is caused by the barrier effect of the Pindos mountains for the winds coming from north-west. The west-east gradient in precipitation continues toward the southern Cyclades reaching less than 300 mm of annual precipitation. The result is a greener and more wooded landscape in the west, for instance in the Ionian Islands, and an apparent dry landscape in the east, for instance in the Cyclads.

About the temperature, the highest average in Greece of July (28°C) occurs in the

Thessalian plain in the vicinity of Athens and southern Crete where daily summer

maximum of 40°C is not uncommon. The January average is 12°C in Iraklion

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(Crete), 10°C in Athens, 5,5°C in Thessaloniki and only 0,8°C in Florina in the extreme northwest of Greece (Phitos et al, 1995).

In the coastal lowlands, snowfall is rare although not exceptional. In the interior of northern Greece there is continuous snow cover already at altitudes of 300-400 m at least for brief period and permanent snow cover for several months – at the 2000 m level on Olympus, for instance.

At last, Greece is a windy country, and especially in coastal areas and on islands there are few calm days. Indeed, in earlier time, windmills were common, and many still exist on some Aegean islands

1.2.5 Flora and Vegetation

Species diversity and endemism

The flora of Greece is one of the richest in Europe, reflecting the mosaic of micro-climate types due to the complex topography. According to Flora Hellenica (Strid & Tan, 1997), the total number of native and naturalized species of vascular plants is currently estimated to comprise 5857 species, included in 1062 genera and 159 families; excluding some aliens which are not fully naturalized, the true figure for number of native and naturalized may rather be around 5700.

This is a remarkably high figure for a relatively small country, equalling or exceeding that of many territories of a comparable size. In Europe, a higher number of species is found only in the Iberian Peninsula, where the flora also includes species of the Atlantic zone. According to the first three of the proposed six volumes of Med-Checklist (c. 44.5% of the total vascular flora in the countries bordering the Mediterranean sea), Greuter (1991) presented some calculation for species diversity and endemism. The highest number of species is found in Anatolia, but this is also by far the largest territory when the Saharian part of Algeria, Lybia and Egypt are disregarded. Spain is in a clear second position, and then follow, at more or less equalling ranking, former Jugoslavia, Italy and Greece (as defined in Med- Checklist), Morocco and France.

Comparatively to the dimensions of these countries, Greece being the smallest

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There is a large number of endemic species in respect to the size of Greece, due to the isolation of the numerous mountains and islands. The number of endemic species is around 740, including the Greek endemism and the endemism of single areas or single mountains of Greece, and excluding other species endemic to the Balkan region: again one of the highest rate for any comparable country or territory in Europe and the Mediterranean area.

According to Med-checklist (Greuter 1991: table 4), the proportion of endemic taxa in different territories is as follows: Anatolia heads the list with 30,8%, followed by Morocco (20,3%), Spain (19,1%), then Greece (14,0%).

Of the taxa treated in the “Mountain Flora of Greece” (Strid, 1986), 47% are endemic to the Balkan Peninsula or a smaller territory, 27% are endemic to Greece, and 17 % are restricted to a single region or a single mountain.

There are significant connections with the Alps and the Carpathians and with the mountain floras of Italy and Anatolia. Many Greek montane taxa have undoubtedly been derived from more widespread planitiary taxa. In particular, the similarity in flora between the Balkan Peninsula and Italy is considerably stronger in the Pindhos than in the Peloponnese and Crete, indicating that connections with Italy are mainly by northern route.

This richness of the Greek flora has historical origins. The peninsulas of Southern Europe enjoyed relatively equable climates during a succession of glacial and interglacial periods during the Pleistocene, and were refuge areas for plants. In contrast, northern Europe is essentially a land of recent immigrants and few populations of plants have had sufficient time since the last glaciation to develop into new species (Phitos et al., 1995)

In absolute terms, the highest numbers of species are found at low and moderate altitudes in the central and northern parts of the Greek mainland where great habitat diversity and a mixture of many phytogeographical elements form the basis for a rich and varied flora. On the other hand, the degree of regional and local endemism increases on a southerly direction, and it’s highest in the mountains of Peloponnese and especially in Crete.

As korologycal groups, the Greek flora is composed of Mediterranean, Central

European and Irano-Caspian elements. The Mediterranean element is predominant,

and four main life forms contribute to give the Mediterranean vegetation its

distinctive features:

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1- Evergreen trees and shrubs, generally with hard and rigid leaves.

2- Small, often aromatic, spiny or grey leaved shrubs, sometimes cushion- shaped and generally evergreen.

3- Bulbous plants (geophytes), mostly flowering in the spring and dying back in the summer, although sometimes autumn-flowering and remaining green throughout the winter.

4- Annual plants which, togheter with the geophytes, produce a colourful flush of flowering in the spring.

Focusing on the geophytic component, as object of the present study, they are well adapted , surviving the dry, hot summer by their underground organs or propaguls.

Anthropic influence on the vegetation

Man and domestic animals have had a profound influence on the vegetation of Greece since ancient times, and what we can see today is a complex mosaic of natural, semi-natural and man-made habitats (Strid & Tan, 2001). Although grazing and browsing by wild herbivorous, as sheep and goats, could be regarded as a natural ecological factor, the impact of forest clearing and the introduction of domestic animals is becoming continuously more severe. Also the destruction of the forest by fire is an important anthopic impact , lamented already by classical authors as Herodothus. Truly natural vegetation is now confined to cliffs, to certain habitats in the mountains, and to place like Mount Athos, protected for several centuries as holy place.

Mediterranean type woodland takes a long time to reach maturity as a climax vegetation, and once destroyed the original forest may never return. The rocky landscape resulting, with dwarf (garigue) or tall (maquis) scrub, so characteristic of lowland of Greece today, is largely a human made artefact, growing after the destruction of the forest.

Also the agriculture contribute to the strong human influence, being Greece the

land of wine, olive trees and citrus woods.

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Phytogeography

For the purpose of Flora Hellenica project, Greece was divided into 13 floristic regions (see the map, fig. 3), the borders of which follow, whenever possible, natural geographical features such as rivers and lowland areas between mountains.

Fig. 3: Phytogeographycal regions of Greece, as defined in the “Flora Hellenica project”.- EAe: East Aegean Islands. EC: East Central. IoI: Ionian Islands. Kik: Kiklades (in a phytogeographical sense).

KK: Kriti and Karpatos. NAe: North Aegean Islands. NC: North Central. NE: North East. NPi:

Northern Pindos. Pe: Peloponnisos. SPi: Southern Pindos. StE: Sterea Ellas (in a phytogeographical

sense). Wae: West Aegean Islands.

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Fig. 4: Map of Greece with the picking places of the plants specimens:

1. Allium ionicum, E98;

2. Allium ionicum, K455;

3. Allium paniculatum L., E59;

4. Allium guttatum ssp. sardoum, K18;

5. Muscari comosum, K424;

6. Muscari commutatum, 18B;

7. Amaryllis belladonna, K510.

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1.3 The picking places of the geophytes studied

The geophytes here investigated have been picked up from different areas of Greece. Most of them are from some Ionian islands, Zakynthos, Kefalonia and Lefkas, and other taxa come from Thessalia, in the eastern Greek mainland, and Mount Parnon, in the south-east of Peloponnese. In the context of a typical Mediterranean climate, this areas are enough different from each other, because of the variable microclimates that Greece includes, due to its complex geomorphology.

The Ionian islands have a relatively more humid climate, showily greener than the drier eastern part of Peloponnese and continental Greece, due to the west-east gradient of precipitation.

Concerning the altitudes of picking, they have been various, going from the sea level to 950 m in mount Parnon.

The plants from the Ionian islands have been picked up in various habitats.

In particular, two populations of Allium ionicum, strictly endemic of these islands, have been taken in the south of Kefalonia. One population comes from an olive grove close to the sea, and the other is from the complex Mount Aenos- Roudi, at an altitude of 650 m.

These mountains are the highest of the Ionian Islands (M. Aenos, 1628 m) and they forms the National Park Aenos-Roudi that protect the Greek fir, Abies cephalonica, an endemic of the Greek mountains referring to the Abies alba group.

Fig. 5: Mount Aenos, Kefalonia, with the typical forest of Abies cephalonica.

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Allium ionicum is nevertheless indicated by Tzanoudakis (1994) as a member of the phrygana community, that prefers the open plant association. It occurs on sloopes, stony ground and semi-disused olive-groves, and it is also present as chasmophitic component of this island.

Allium paniculatum L. have been found in Lefkas (from Greek λευκός= white) on a calcareous rocky substrate that well characterize the west coast of this island (see fig. 6). This unit doesn’t seem to have particular ecologic preferences, according to Flora Europaea (1980); the place of picking is quite inhospitable being a steep and calcareous cliff.

The specimens of Allium guttatum ssp. sardoum comes from the south coast of Zakynthos. It was found in a sandy beach in Laganas Bay. This taxon is indicated by Flora Europaea to prefer generally dry places also for other south European countries where it grows. With regards to the human influence of the picking place, Laganas Bay is a National Marine Park istituted to protect the nesting of the turtle Caretta caretta.

Fig. 6: Lefkas, Ionian Islands: calcareous cliff of the south-west coast of the island.

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The population of Muscari comosum has been picked up in uncultivated fields in Thessalia, close to the Pinios river. This region is relatively dry, being situated in the east Greek mainland, because of the west-east precipitation gradient. Anyway this taxon has a wide ecological tolerance, appearing to have no special demands on soil conditions, and it’s generally found also in extensively cultivated areas all over its wide area of distribution.

The specimens of Muscari commutatum have been picked up in Mount Parnon, in the south east of Peloponnese. It was growing in a deciduous forest with Castanea sativa and Quercus sp. pl., at an altitude of 950 m.

At last, the population of Amaryllis belladonna was found in an olive grove in Zakyntos (fig. 8). As introduced and naturalized element in the Greek flora, it may escaped from the garden cultivation and it may began to reproduce by own means.

Because of the tropical-subtropical origin of this species, stricly indigenous in south Africa, it prefer hot and dry climates

Fig.7: coastal vegetation on a sandy beach of the Ionian Islands.

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.

2. Materials and methods

2.1 Materials

About all the plants studied in their karyologycal aspect, the following informations are indicated: the cultivation number of each specimen; the locality of origin with the relative geographic coordinates; the name of the picker and the date of picking.

Allium ionicum Brullo & Tzanoud., E98.

Ionian Islands, Kefalonia, Mount Roudi, between the mountains Roudi & Enos, alt. 650 m. 38

o

10' N, 20

o

38' E. Legit Niki Katsouni 16-06-2002.

Fig. 8: typical olive grove of Zakynthos, Ionian Islands.

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Allium ionicum Brullo & Tzanoud., K455.

Ionian Islands, Kefalonia, Avithos, Kalligata plain, in olive groves, alt. 90 m. 38

o

07' N, 20

o

33' E. Legit Niki Katsouni 19-2-2001.

Allium paniculatum L., E 59.

Ionian Islands, Lefkas, close to the road between the villages Dragano and Athani, calcareous substrate. 38

o

40' N, 20

o

34' E. Legit E. Kriemadi 19-11-2001.

Allium guttatum Steven ssp. sardoum (Moris) Stearn, K18.

Ionian Islands, Zakynthos, east part of the island, Kalamaki, in Laganas bay, sandy places by the sea. Alt. c. 0-5 m. 37

o

44' N, 20

o

53' E. Legit Georgia Kamari 5- 4-2004.

Muscari comosum (L.) Miller, K424.

Thessalia, Nomos Larissis, Pinios river, north of the village Stomion in uncultivated fields, alt. c. 30 m. 39

o

52' N, 22

o

43' E. Legit P. Bareka & D. Barekas 2-5-2000.

Muscari commutatum Guss.,18b.

Peloponnisos, Nomos Arkadias, Mt Parnon, c. 0,5 km from the village of Agios Petros on the way to Tripolis, deciduous forest with Castanea sativa and Quercus sp.pl. alt. 950m. 37

o

19' N, 22

o

32' E. Legit Georgia Kamari et al. s.n. 3-6-1995.

Amaryllis belladonna L., K510.

Ionian Islands, Zakynthos, close to the village Katastari, in olive groves (naturalized). 37

o

50' N, 20

o

45' E. Legit Georgia Kamari 15-5-2003.

2.2 Methods

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The plants studied were collected in the field and then cultivated in the experimental garden of the Institute of Botany of Patras. The samples of each species are kept in the Herbarium of Patras (UPA). To conduct a caryologycal investigation, the root tip meristems in metaphase of potted plants were collected for the chromosome preparation, and then were treated as follows.

A pre-treatment for 5-6 hours in a solution of colchicine and hydroxyquinoline was applied at about 5°C before fixation. After fixation in Carnoy (3:1 mixture of glacial acetic acid and absolute ethanol) for 24 hours, the root tips were stored in ethanol 80%.

The following procedure involved the hydrolysis in HCl 1 N at 60°C for 11-12 minutes, the staining with Feulghen (leucobasic fuxin) for about 1 hour and half, cutting of the meristems and squashing them in glacial acetic acid.

The microscope investigation followed to analyze the metaphasic plate, and the microphotographs of the plates here presented were taken.

The nomenclature of Levan et al. (1964) for centromeric positions on

chromosomes was used in order to obtain the idiogram and the idiogrammatic

formula for each taxa investigated.

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