the effect of heat shock on the formaldehyde cycle in germinating acorns of european turkey oak.the effect of heat shock (40 degrees c) on the formaldehyde cycle has been studied in european turkey oak (quercus cerris l.) acorns germinated to a 10% increase in mass. hydroxy-methyl groups bonded to sulfur, oxygen and nitrogen atoms were made to react with dimedone and the derivative obtained (formaldemethone), which represented the endogenous formaldehyde level, was determined by high performance liquid chromatography. qualitative alterations of methyl donors and acceptors in the response o ...199810526981
annual fluctuation in amplitudes of daily variations of electrical signals measured in the trunk of a standing tree.electrical potential differences between electrodes inserted in eight selected sites of the trunk of a turkey oak (quercus cerris) and the ground have been recorded continuously since november 1997. the mean amplitudes of daily electric variations were determined for time intervals when the meteorological and atmospheric electricity conditions were undisturbed. it was found that the mean daily amplitudes show a characteristic annual fluctuation. both in 1998 and in 1999 two peaks were observed: ...200010923212
differential success in northwards range expansion between ecotypes of the marble gallwasp andricus kollari: a tale of two lifecycles.the marble gallwasp andricus kollari has a native range divided into two geographically separated lifecycles. in eastern europe and turkey, the lifecycle involves a sexual generation on turkey oak, quercus cerris, while in iberia and north africa the sexual generation host is cork oak, q. suber. over the last 500 years, a. kollari has expanded its range into northern europe, following human planting of q. cerris from italy and the balkans. we ask: (i) what is the genetic relationship between eas ...200111298986
identification, measurement and interpretation of tree rings in woody species from mediterranean climates.we review the literature dealing with mediterranean climate, vegetation, phenology and ecophysiology relevant to the understanding of tree-ring formation in mediterranean regions. tree rings have been used extensively in temperate regions to reconstruct responses of forests to past environmental changes. in mediterranean regions, studies of tree rings are scarce, despite their potential for understanding and predicting the effects of global change on important ecological processes such as desert ...200312620063
epiphytic lichens as sentinels for heavy metal pollution at forest ecosystems (central italy).the results of a study using epiphytic lichens (parmelia caperata) as sentinels for heavy metal deposition at six selected forest ecosystems of central italy are reported. the woods investigated are characterized by holm oak (quercus ilex), turkey oak (quercus cerris) and beech (fagus sylvatica) and represent the typical forest ecosystems of central italy at low, medium and high elevations, respectively. the results showed that levels of heavy metals in lichens were relatively low and consequent ...200312685761
crown condition surveys in italian forests: issues in reporting findings.this study examines defoliation and discoloration findings collected throughout the italian level i network between 1997 and 2000. prior to this period no quality assurance procedures had been implemented, so that earlier findings cannot be considered reliable. the aim of the study is to compare different indices used in reporting findings, in order to determine the full potential and limitations of each. in international surveys, findings are normally expressed in terms of individual trees pres ...200312841687
characterization of germination with physical parameters: correlation of relative mass and density as an indicator function of the germination of european turkey oak acorn.during germination of european turkey oak acorn (quercus cerris l.), a linear relationship was established between mass and density. water take-up induced by osmotic pressure of imbibition was established to be independent of the volume of the acorn. development of the germinating acorn can be characterized by its physical parameters of relative mass (the mass of the germinating acorn divided by its mass at the beginning of germination) and density. linear correlation between the increment of re ...200415380381
morphological-anatomical characterization and molecular identification of tomentella stuposa ectomycorrhizae and related anatomotypes.species in the genus tomentella (thelephoraceae) belong to the most frequent and widespread ectomycorrhizal (em) fungi found in temperate and boreal forests. although several unidentified tomentelloid morphotypes have been presented as common members of em communities in coniferous and broad-leaved forests, few tomentelloid em have been identified and described in detail. in this study, ten tomentelloid em isolates collected from populus alba, quercus cerris and picea abies stands in hungary and ...200515517422
real-time pcr detection of biscogniauxia mediterranea in symptomless oak tissue.real-time pcr, based on taqman chemistry, was used to detect biscogniauxia mediterranea, a fungal pathogen that after a long endophytic phase may cause charcoal disease in oak trees.200515960754
pattern of secondary thickening in a quercus cerris root system.we investigated changes in the pattern of secondary thickening along first-order lateral roots of quercus cerris l. (turkey oak), a dominant species in the mixed forests of the mediterranean basin. the eccentricity of radial growth was analyzed relative to the gravimetric center of the root, a measure that is unaffected by year-to-year variation in growth ring width. in cross sections collected at the taproot-lateral root junction, radial growth was greatest on the upper side of the root. howeve ...200717241982
the phylogeographical clade trade: tracing the impact of human-mediated dispersal on the colonization of northern europe by the oak gallwasp andricus kollari.human dispersal of organisms is an important process modifying natural patterns of biodiversity. such dispersal generates new patterns of genetic diversity that overlie natural phylogeographical signatures, allowing discrimination between alternative dispersal mechanisms. here we use allele frequency and dna sequence data to distinguish between alternative scenarios (unassisted range expansion and long range introduction) for the colonization of northern europe by an oak-feeding gallwasp, andric ...200717594446
leaf traits and tree rings suggest different water-use and carbon assimilation strategies by two co-occurring quercus species in a mediterranean mixed-forest stand in tuscany, italy.we compared the water-use characteristics of co-occurring mature quercus cerris l. and quercus pubescens willd. trees growing in resource-limited (mainly water) hilly habitats in tuscany, italy. the species differed in their distribution along soil water gradients and in their access to, and use of, water, even though the study year was wetter than average, though with a summer drought. compared with q. cerris, q. pubescens had greater access to soil water (less negative predawn water potentials ...200717938105
fossil oak galls preserve ancient multitrophic interactions.trace fossils of insect feeding have contributed substantially to our understanding of the evolution of insect-plant interactions. the most complex phenotypes of herbivory are galls, whose diagnostic morphologies often allow the identification of the gall inducer. although fossil insect-induced galls over 300myr old are known, most are two-dimensional impressions lacking adequate morphological detail either for the precise identification of the causer or for detection of the communities of speci ...200818559323
fungal endophytes in mediterranean oak forests: a lesson from discula quercina.fungal endophytes that colonize forest trees are widespread, but they are less well known than endophytes infecting grasses. the few studies on endophytes in trees mainly concern the tropical areas and the northernmost latitudes, while similar investigations in the mediterranean region have so far been scarce and incidental. endophytes are studied mostly in economically important forests suffering from diseases, such as oak forests. one common endophyte that has received some study on oak is the ...200818944185
evaluation of antioxidative, protective effect against h(2)o(2) induced cytotoxicity, and cytotoxic activities of three different quercus species.quercus species are used as antidiarrheic, for the treatment of hemorrhoid, oral and anal mucosa inflammation. these tree species have been of interest to researchers because of their usage in folk medicine, consumption as food, beverage and especially usage of oak woods for construction in wine barrels. the dpph, so and no radical scavenging activities, protective effect against h(2)o(2) induced cytotoxicity as well as their cytotoxic activity against hep-2 human larynx epidermoid carcinoma cel ...201122067294
presence of host-seeking ixodes ricinus and their infection with borrelia burgdorferi sensu lato in the northern apennines, ticks were collected in the northern apennines, italy, by dragging at 35 sites, at altitudes ranging from 680 and 1670 m above sea level (asl), from april to november, in 2010 and 2011. ixodes ricinus (4431 larvae, 597 nymphs and 12 adults) and haemaphysalis punctata (11,209 larvae, 313 nymphs, and 25 adults) were the most abundant species, followed by haemaphysalis sulcata (20 larvae, five nymphs, and 13 adults), dermacentor marginatus (42 larvae and two adults) and ixodes hexagonu ...201626964552
quercus cerris extracts limit staphylococcus aureus biofilm formation.quercus cerris l., fagaceae has been used in traditional mediterranean medicine for numerous purposes, including anti-infective therapies for diarrhea and wound care.201223127649
introduction to distribution and ecology of sterile conks of inonotus obliquus.inonotus obliquus is a fungus that causes white heart rot on several broad-leaved species. this fungus forms typical charcoal-black, sterile conks (chaga) or cinder conks on infected stems of the birche (betula spp). the dark brown pulp of the sterile conk is formed by a pure mycelial mass of fungus. chaga are a folk remedy in russia, reflecting the circumboreal distribution of i. obliquus in boreal forest ecosystems on betula spp. and in meridional mountain forests on beech (fagus spp.) in russ ...200823997626
geographic and between-generation variation in the parasitoid communities associated with an invading gallwasp, andricus quercuscalicis (hymenoptera: cynipidae).the knopper gallwasp andricus quercuscalicis burgsdorf 1783 (hymenoptera: cynipidae) has invaded western and northern europe from southern and eastern europe over the last 400 years. a. quercuscalicis has two alternating generations, which differ in phenology, structure, and host oak species. this study describes geographic variation in the community in the tiny catkin galls of the sexual generation on turkey oak, quercus cerris, and compares the patterns obtained with those in the community att ...199528307357
the melliferous potential of forest and meadow plant communities on mount tara (serbia).the apiflora of 34 forest and meadow plant communities in tara national park was studied with the aim of assessing their melliferous potential and their contribution to bee pasture during the vegetation period. the melliferous plants were analyzed individually from the aspect of their flowering phenology, abundance, and the intensity of nectar and pollen production, as well as the production of honeydew. the melliferous potential of each investigated plant community was theoretically assessed on ...201323905735
suberized cell walls of cork from cork oak differ from other species.plants have suberized cells that act as protective interfaces with the environment or between different plant tissues. a lamellar structure of alternating dark and light bands has been found upon transmission electron microscopy (tem) observation of cork cells and considered a typical feature of the suberized secondary wall. we observed cork cells from periderms of quercus suber, quercus cerris, solanum tuberosum, and calotropis procera by tem after uranyl acetate and lead citrate staining. a la ...201020804640
karyotypes, b-chromosomes and meiotic abnormalities in 13 populations of alebra albostriella and a. wahlbergi (hemiptera, auchenorrhyncha, cicadellidae) from this work 13 populations of the leafhopper species alebra albostriella (fallén, 1826) (6 populations) and a. wahlbergi (boheman, 1845) (7 populations) (cicadellidae: typhlocybinae) from greece were studied cytogenetically. we examined chromosomal complements and meiosis in 41 males of a. albostriella sampled from castanea sativa, fagus sylvatica and quercus cerris and in 21 males of a. wahlbergi sampled from c. sativa, acer opalus and ulmus sp. the species were shown to share 2n = 22 + x(0) a ...201324455103
mycorrhization of quercus robur l., quercus cerris l. and corylus avellana l. seedlings with tuber macrosporum vittad.tuber macrosporum vittad. is not a common truffle species, but with remarkable organoleptic qualities and much economic interest. after the addition of truffle spore slurry, 30 seedlings of quercus robur l., quercus cerris l. and corylus avellana l. were grown inside a greenhouse for 11 months before evaluation of the mycorrhizal level. two different potting mixes were used: a natural soil-based potting mix for q. robur, q. cerris and c. avellana and a peat-based potting mix for q. robur. quercu ...201222565651
assessing ozone and nitrogen impact on net primary productivity with a generalised non-linear model.some studies suggest that in europe the majority of forest growth increment can be accounted for n deposition and very little by elevated co(2). high ozone (o(3)) concentrations cause reductions in carbon fixation in native plants by offsetting the effects of elevated co(2) or n deposition. the cause-effect relationships between primary productivity (npp) of quercus cerris, q. ilex and fagus sylvatica plant species and climate and pollutants (o(3) and n deposition) in italy have been investigate ...201323078996
indicator species of essential forest tree species in the burdur district.the forests of burdur district for long have been subjected to over grazing and individual selection. as a result of this, majority of the forest areas in the district were degraded. in the district, afforestation efforts included majority of forestry implementations. it is well known that selecting suitable species plays an important role for achieving afforestation efforts. in this context, knowing the indicator species among the target species would be used in afforestation efforts, studies o ...201526591889
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