Abstract: Greece is characterized by high plant diversity (5800 species) and endemism (15.6%). This study attempts a first overall assessment of the taxonomy, distribution, traits and conservation status of the Greek endemic plants. The endemic species belong to 56 families and 242 genera. Most of the endemic plants have a narrow geographical and altitudinal distribution range. The southern floristic regions are richer in endemic species. The species area relationships for endemics (EARs) for island and continental floristic regions explain over 50% of the variation in number of species and are characterized by steep curves. Analysis of the distributional pattern of the endemics by similarity coefficients offers useful insights into the palaeogeography and biogeography of Greece. The endemic species occur at all altitudes, but the altitudinal distribution shows a predominance of local endemics at 0â600 m in the island regions and in higher zones in the continental regions. The life form spectra show a predominance of hemicryptophytes and chamaephytes. This trait seems indicative of their habitat and adaptive strategy and may be related to speciation processes. The overview of the conservation status of the Greek endemics indicates that over 40% of the taxa are threatened or near threatened.
Abstract: We examined the relationship between plant species richness and biogeographical
variables (island area, island maximum elevation, distance from nearest inhabited
island, distance from nearest mainland) using a data set comprising 201 islands of the
Aegean archipelago. We found that endemic species richness was strongly correlated to
total species richness. Single-island endemic species richness was most strongly correlated
to island maximum elevation, and then to island area, with an apparent small island effect
for islands smaller than 47 km2. Total species richness was most strongly correlated to
island area (with no apparent small island effect), and less strongly correlated to island
maximum elevation. Distance from the mainland or other inhabited islands displayed
limited predictive value in our data set. The slope of the relationship between species
richness and geographical factors (island area, elevation, distance from island/mainland)
was steeper for endemic species richness than for total richness. Finally, the different
scales of endemicity (single-island endemics, island group endemics and Aegean regional
endemics) displayed similar qualitative trends and only differed quantitatively. Thus, we
conclude that different biogeographical factors act as drivers for total species richness than
for endemic species richness.
Abstract: Recent comprehensive data provided through the DAISIE project (www.europe-aliens.org) have facilitated the
development of the first pan-European assessment of the impacts of alien plants, vertebrates, and invertebrates â
in terrestrial, freshwater, and marine environments â on ecosystem services. There are 1094 species with documented
ecological impacts and 1347 with economic impacts. The two taxonomic groups with the most species
causing impacts are terrestrial invertebrates and terrestrial plants. The North Sea is the maritime region that suffers
the most impacts. Across taxa and regions, ecological and economic impacts are highly correlated. Terrestrial
invertebrates create greater economic impacts than ecological impacts, while the reverse is true for terrestrial
plants. Alien species from all taxonomic groups affect âsupportingâ, âprovisioningâ, âregulatingâ, and âculturalâ
services and interfere with human well-being. Terrestrial vertebrates are responsible for the greatest range of
impacts, and these are widely distributed across Europe. Here, we present a review of the financial costs, as the first
step toward calculating an estimate of the economic consequences of alien species in Europe.
Abstract: Within the framework of the EC funded project DAISIE literature data regarding the alien flora
of Greece were compiled in a database. The data collected concern taxonomy, distribution, origin,
introduction pathway, status, life and growth form, flowering period, fruit type, habitat etc.
Data on 326 taxa reported for Greece have been compiled in this database. Approximately 40%
of these taxa are naturalized. The richest families in number of taxa, comprising approximately
30% of the total, are Gramineae, Compositae and Leguminosae, while Amaranthus is by far
the richest genus consisted of 18 taxa. As far as their life form is concerned, the majority are
therophytes followed by phanerophytes and hemicryptophytes. Chorological analysis showed
that most of the taxa are of American origin (38%) As it was expected, most of the alien taxa
grow in disturbed and man-made habitats.
Abstract: Freshwater algal biomass and orange and lemon peels were assessed as tissue paper pulp supplements. Cellulose and hemicellulose
contents of algal biomass were 7.1% and 16.3%, respectively, whereas for citrus peels cellulose content ranged from 12.7% to 13.6%
and hemicellulose from 5.3% to 6.1%. For all materials, lignin and ash content was 2% or lower, rendering them suitable for use as paper
pulp supplements. The addition of algal biomass to paper pulp increased its mechanical strength significantly. However, brightness was
adversely affected by chlorophyll. The addition of citrus peels in paper pulp had no effect on breaking length, increased bursting strength
and decreased tearing resistance. Brightness was negatively affected at proportions of 10%, because citrus peel particles behave as coloured
pigments. The cost of both materials is about 45% lower than that of conventional pulp, resulting in a 0.9â4.5% reduction in final
paper price upon their addition to the pulp.
Abstract: Cyprus, despite its small geographic scale, is characterized by a large topographic diversification concerning climate and soil morphology. As a result of these conditions, Cyprus has a large and unique flora of 1910 taxa, with a high (7.3%) percentage of endemism. This work is at a preliminary stage and is a part of a joint project between Cyprus and Greece funded by the Cyprus Research Promotion Foundations. The aim is to study the potential of six endemic species of the Cyprus flora (Arabis purpurea, Centaurea akamantis, Onosma fruticasa, Origanum cordifolium, Ptilostemon chamaepeuce and Euphorbia veneris), for use in sustainable commercial floriculture and at the same time, the project aims at the conservation of these species since all of them are endemic and two of them Centaurea akamantis and Origanum cordifolium are strictly protected by the Bern Convention.
Tests on seed germination of these species at different temperatures, showed that 81% of the seeds of Arabis purpurea, germinated at 20oC between the 32nd and the 40th day and 72 - 76% of Ptilostemon chamaepeuce var.cypria, between 10 and 16 days. A high percentage of Origanum cordifolium (82%), germinated at the temperature of 10oC and 79% at 15oC, in both cases after 6 days. For Centaurea akamantis, the percentage of seed germination was lower and reached 70% in 14 days at 15oC and 55% in 25 days at 20oC. Best results for Euphorbia veneris propagated by tissue culture, were observed when stem nodes without leaves were used as explants. It is shown that 0,5 mg.l-1 ÎÎP in Îuphorbia veneris led to satisfactory bud differentiation and shoot proliferation.
Abstract: Despite its relatively small length (650 m), Sekania beach on Zakynthos island (Ionian sea) is the single most important Caretta
caretta L. nesting beach in the Mediterranean Sea. The aim of this work was to tackle the possible relationships of sand and
vegetation characteristics with the nesting activity of sea turtle C. caretta. The vegetation structure and distribution along the sandy
beach was studied with the use of line transect method. Grouping of plant species was revealed through an ordination method. Plant
groups were distinguished and mapped. Sand texture, pH, and organic matter were measured on the transects. Nesting activity was
also mapped on the beach and hatching success was recorded. It was concluded that where sand salinity is high enough to prevent
vegetation development, wet sand is located at a threshold depth for excavating an egg chamber. It seems that well-sorted sand
grains favor nesting activity on the beach. The increase of fine sand â from east to west â is proportional with the reduction of
nesting density. The data collected for this study are organized in a GIS database, which could be the basis for the establishment of
an integrated monitoring system for Sekania beach.
Abstract: Fiber dimensions and lignin and cellulose content of various highly productive, non-wood plants and agricultural residues
were examined to assess their suitability for paper production. Plants like kenaf (Hibiscus cannabinus L.) and giant reed (Arundo
donax L.) internodes gave very good derived values, especially slenderness ratio, which is directly comparable to some softwood
and most hardwood species. Cotton (Gossypium hirsutum L.) stalks, miscanthus (Miscanthus à giganteus) and switchgrass
(Panicum virgatum L.) have shorter fibers resulting to poorer flexibility and Runkel ratios, but still satisfactory slenderness
ratios. Finally, fibers from olive tree (Olea europea L.) and almond tree (Prunus dulcis L.) prunings presented relatively short
and thick fibers producing the poorest derived values among all the species examined. Fiber dimensions did not differ significantly
within each species, when samples from different stalks/branches or different positions (base, middle top) were examined. The
only exception were cotton stalks, where those differences did not have any significant effect on fiber derived values.
Chemical analysis of the raw plant materials revealed satisfactory levels of -cellulose content (close to 40%) and Klason
lignin content (<30%) compared to those of hardwoods and softwoods. Relatively increased (>25%) lignin content in miscanthus,
switchgrass and almond prunings may require additional pulping time and chemical charge compared to those of other non-wood
raw materials. Analysis of samples at various heights/lengths of the plant materials showed that lignin and cellulose content
depends on tissue maturity, but does not change significantly within each species.
Abstract: Photoinhibition of seed germination was shown for Allium staticiforme, Brassica tournefortii, Cakile maritima and Otanthus maritimus, all plant species inhabiting sandy coasts of the Mediterranean Sea. Germination of A. staticiforme was found to be typically Mediterranean in regard to its temperature range (> 0-20 °C), while B. tournefortii germinated optimally at intermediate temperatures (15-25 °C). Light sensitivity was more pronounced in the latter species and 50% inhibition of seed germination was obtained with photon flux densities of approximately 0.1 and 0.015 mol m-2 d 1 in A. staticiforme and B. tournefortii, respectively. However, the slopes of the regression lines of germination plotted against the logarithm of white light flux density are similar in both species. From monthly experiments performed under fluctuating conditions of temperature and light, simulating the climate of Athens throughout the year, optimal germination response peaked in 'winter' conditions for A. staticiforme, while a bimodal pattern was observed for B. tournefortii (maxima at the warm ends of the rainy season). In contrast to the other plants, a fifth species tested, Crithmum maritimum, showed an absolute light requirement, probably related to the rocky habitats of the species; the optimum germination period coincided with the rainy season. Pot experiments with seeds of the five species buried at various depths confirmed that maximum emergence is favoured by shallow depths (0.5-1 cm). It is concluded that seed germination in maritime plants of the Mediterranean rim is mediated by a photoinhibition mechanism which can be considered an adaptation strategy against surface seedling establishment at the harsh, sandy or shingle, sea coast habitats.
Abstract: The effects of Osmoconditioning on the germination at 15 and 25 °C of pepper (Capsicum annuum L.) seeds were studied over a 3-year period with respect to temperature of storage. Untreated seeds stored at 5 °C showed high germinability throughout the entire storage period, whereas untreated seeds stored at 25 °C showed a progressive decline in germinability, especially when assayed at 15 °C. Seeds that had been osmoconditioned prior to storage retained a high level of germinability irrespective of either storage or germination temperatures. When seeds that had been stored at 25 °C were osmoconditioned after storage, there was a significantly higher germinability (assayed at 15 °C) in comparison with the corresponding untreated seeds. Seeds that were osmoconditioned twice (prior to and after storage) germinated in a similar way to those that had been osmoconditioned once only.
Abstract: The yellow horned-poppy Glaucium flavum Crantz shows a final dark germination which is of characteristically 'mediterranean' type (maximal response at the temperature range 5-15 °C), though a considerable broadening is brought about, both by a red light pulse and a stratification treatment. Seeds imbibed in darkness at 25 °C for even a few hours are induced to develop a secondary dormancy (thermodormancy) which can be released by light and stratification. The well known time dependence of light sensitivity and the gradually imposed induction of light indifference at supraoptimal temperatures have also been shown. Seeds imbibed under regimes simulating those met naturally in Greece during November or April, do not germinate when illuminated with white light (ζ = 1.26). Full manifestation of germination occurs either in complete darkness or under various, red-enriched light conditions (ζ higher than 2.07). A partial promotion is observed with very low fluence rates of white light (in the order 10-3 10-4 of daylight). The existence of a surface-avoiding seedling emergence mechanism based on lightinhibited seed germination was verified in a pot experiment under natural conditions, with seeds buried to various depths. Only those seeds buried at 0.5 cm germinate optimally and readily after the onset of the rainy season (November-December) although those at 1 and 2 cm also germinate to a considerable extent.
Abstract: Sweet pepper seeds were osmotically conditioned in 0.4 m mannitol solution for 4 d (at 25 °C, in darkness) before or after storage at 35 °C for up to six months, and their germination and viability was compared with that of untreated seeds stored under the same conditions. Seeds that had been osmoconditioned prior to storage retained a high rate of germination and germinated to a high final percentage (from 80 to 50 per cent) at both 15 and 25 °C throughout the storage period. By contrast, both the rate and total level of germination of untreated pepper seeds declined rapidly at both germination temperatures, and by three months of storage the total level of seed viability was already less than 10 per cent. Seeds that were first stored at 35 °C, and then osmoconditioned just prior to germination, showed a decline in germinability which when tested at 25 °C was the same as for untreated seeds, while tested at 15 °C occurred at a slightly slower rate than for untreated seeds. It is evident that Osmoconditioning prior to storage, in addition to the acceleration of germination, resulted in a dramatic delay of the ageing rate, thus increasing considerably the longevity of seeds. On the other hand, Osmoconditioning after storage did not seem to have any significant effect on seed viability, though it enhanced the germination rate.
Abstract: Roots of maize seedlings grown under continuous broad spectrum far-red (FR) light accumulated large quantities of anthocyanins (larger than those observed in shoots). Similar results were also obtained under continuous broad spectrum blue (B) light. Excision of the shoot at different ages and subsequent illumination with continuous-FR (c-FR) or continuous-B (c-B) of the 'root + endosperm' system caused an anthocyanin accumulation significantly higher than that observed in roots of intact plants. Intermittent monochromatic red (i-R) (cycles of 2 h) promoted anthocyanin appearance while its action was reversed when monochromatic short FR irradiation followed each R one. The data presented suggests the presence and function of phytochrome in maize roots and seem to be a final negative answer to the controversial contribution of photosynthesis to HIR of anthocyanin accumulation.
