首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
From mid-elevation pine forest on the Aegean Sea island of Thasos 8 additional Cladonia species for the lichen mycota of Greece are reported.Most have a wide distribution in Europe and reach their southern limit in Greece.From schistose rock in the same area and on Evvia a new species is described,Cladonia graeca,which is probably related to C.macrophylla and C.decorticata but contains fumarprotocetraric acid instead of psoromic or perlatolic acid.  相似文献   

2.
Thrombin acts on mammalian cells through specific, the so-called protease-activated receptors (PARs). The thrombin action is mediated via three out of four known types of these receptors PAR(1, 3, 4). Mammalian thrombin receptors, apart from performance of other functions, control cardiac and vascular contractility. It is not known whether receptors of such kind exist in invertebrate animals. In the present work we have showed for the first time that thrombin in the concentration range of 0.01-1 units/ml increases amplitude of contractions of the isolated heart ventricle of the edible snail Helix pomatia. Its effect is reproduced by peptide ligands of receptors PAR1 and PAR4 that have sequences Ser-Phe-Leu-Leu-Arg-Asn (SFLLRN) and Glu-Tyr-Pro-Gly-Lys-Phe (QYPGKF), respectively. A potent activati of cardiac contractivity of H. pomatia is serotonin. A comparative study of mechanisms of action of serotonin and thrombin on the edible snail heart was carried out. cAMP participates in transduction of signal from serotonin receptors. On the membrane preparation from the H. pomatia heart, it was shown that thrombin and peptide ligands PAR(1, 4), unlike serotonin, did not increase adenylyl cyclase activity. Thus, mechanism of activation of cardiac contractivity of H. pomatia by thrombin differs from the action mechanism of serotonin. It is suggested that molluscs have receptors homologous to protease activated mammalian receptors.  相似文献   

3.
Biebersteinia orphanidis was considered extinct from Greece and Europe as it had not been collected since Orphanides' type collection of 1851. Its rediscovery is reported here from a mountain close to the classical locality. The species serves as a distinct phytogeographical link between the floras of Greece and Anatolia. In Greece, at least, it grows in a critically low number of individuals. Data on the species habitat and population status are given, and potential threats to its survival are discussed.  相似文献   

4.
Geranium kikianum Kit Tan & G. Vold sp. nov. (Geraniaceae) is illustrated and described as a new species endemic to Greece. It occurs beside streams and other wet places in open Pinus nigra forest at the foothills of Mt Taigetos in the southern Peloponnese. It is closely related to G. macrorrhizum, a species more widely distributed in southern and central Europe, ranging from the southern Alps to the Balkan Peninsula. It differs from the latter by its smaller and narrower deflexed petal limb, slender claw and occurrence in wet habitats. The genome sizes of G. kikianum and of Greek populations of G. macrorrhizum are presented here for the first time. The nuclear DNA content (2C values) of 2.84 pg for G. kikianum and 2.83 and 2.87 pg for two G. macrorrhizum populations from Greece probably corresponds to a 2n=92 cytotype while the smaller genome size of 1.45 pg in a population of G. macrorrhizum from Mt Smolikas, Greece may correspond to a 2n=46 cytotype.  相似文献   

5.
Cotton is the most important textile plant in the world and is one of the most important crops for the production of oilseed. Because of its worldwide economic importance, new cultivars are constantly being released in the world and consequently in the Greek market, as Greece is the largest producer in Europe. We used simple sequence repeat (SSR) markers for the identification and the phylogenetic analysis of the most widely cultivated cotton cultivars in Greece. Initially, we used 12 pairs of SSR molecular markers for the analysis of 29 cultivars of Gossypium hirsutum and an interspecific hybrid (G. hirsutum x G. barbadense). Of the 12 pairs of SSR primers, 11 amplified polymorphic products, while one pair did not amplify any product. Globally, 17 polymorphic marker loci were identified. Two to four different alleles were amplified at each genomic locus, with a mean of 2.53 alleles per locus. Among the 30 genotypes that we analyzed, the polymorphism information content ranged from 0 to 0.548, with a mean of 0.293. Three main groups were formed among the 30 genotypes when a phylogenetic analysis was performed using UPGMA. Computational analysis of each molecular marker separately showed an association of SSR markers with agronomic traits such as fiber quality. To our knowledge, this is the first in-depth molecular analysis of cotton cultivars grown in Greece using SSR markers. An analysis of association of SSR markers with fiber quality traits of 29 cotton cultivars is reported for the first time.  相似文献   

6.
7.
高乞  黄俞淞  蒙涛 《西北植物学报》2012,32(12):2566-2567
报道了中国蜘蛛抱蛋属一新记录种———两色蜘蛛抱蛋。该种原产于越南,在中国为首次记录。本文对该种的特征进行了详细描述,尤其是对该种的花果期和果实的特征进行了重新描述和补充。凭证标本存放于广西植物研究所标本馆(IBK)。  相似文献   

8.
Native to Asia, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is considered an invasive alien ladybird in Europe and North America, where it was widely introduced as a biological control agent of aphids and coccids. In Europe, H. axyridis was sold by various biological control companies from 1995 in France, Belgium and the Netherlands, and was also intentionally released in at least nine other countries. It has spread very rapidly, particularly since 2002, and is now regarded as established in thirteen European countries. The established range extends from Denmark in the north to southern France in the south, and from Czech Republic in the east to Great Britain in the west. In this paper we map the spread and distribution of H. axyridis in Europe, and examine the situation on a country-by-country basis. We report first records of the species in five countries; Spain, Sweden, Denmark, Czech Republic and Italy; and first evidence of H. axyridis establishment in the latter three countries. Despite releases of H. axyridis in Portugal, Spain and Greece, there is little evidence of establishment in southern Europe. It is predicted that the spread and increase within Europe will continue and that H. axyridis will become one of the most widely distributed coccinellids in the continent.  相似文献   

9.
Thrombin acts on mammalian cells through the specific, so-called protease-activated receptors (PARs). The thrombin action is mediated via three out of four known types of these receptors—PAR1,3,4. Mammalian thrombin receptors, apart from performance of other functions, control cardiac and vascular contractility. It is not known whether receptors of such kind exist in invertebrate animals. In the present work we have showed for the first time that thrombin in the concentration range of 0.01–1 units/ml increases amplitude of contractions of the isolated heart ventricle of the edible snail Helix pomatia. Its effect is reproduced by peptide ligands of receptors PAR1 and PAR4 that have sequences Ser-Phe-Leu-Leu-Arg-Asn (SFLLRN) and Glu-Tyr-Pro-Gly-Lys-Phe (QYPGKF), respectively. A potent activator of cardiac contractility of H. pomatia is serotonin. A comparative study of the mechanisms of action of serotonin and thrombin on the edible snail heart was carried out. cAMP participates in transduction of signal from serotonin receptors. On the membrane preparation from the H. pomatia heart, it was shown that thrombin and peptide ligands PAR1 and PAR4, unlike serotonin, did not increase adenylyl cyclase activity. Thus, mechanism of activation of cardiac contractility of H. pomatia by thrombin differs from that of serotonin. It is suggested that molluscs have receptors homologous to protease-activated mammalian receptors.  相似文献   

10.
Four benthic algae are reported here for the first time in the North Carolina flora. The new brown algal genus and species, Onslowia endophytica Searles, is described as an endophyte of Halymenia floridana from the North Carolina continental shelf. New records of Boodleopsis pusilla and Naccaria corymbosa from North Carolina constitute range extensions of these tropical species on the American coast north from Florida. Blastophysa rhizopus, an endophyte and epiphyte known from the North Atlantic coast of Europe and America as well as the Caribbean is reported from North Carolina for the first time and in a new host, Predaea feldmannii.  相似文献   

11.
《Journal of bryology》2013,35(4):807-810
Abstract

Hedwigia stellata Hedenäs, here reported for the first time from the British Isles, is common and widely distributed. H. ciliata var. ciliata is rare, var. leucophaea very rare.  相似文献   

12.
13.
The chemical investigation of the methanol extract of the whole plant of Gymnanthemum theophrastifolium (Schweinf. ex Oliv. & Hiern) H.Rob. (Asteraceae) led to the isolation of a new elemane-type sesquiterpene ( 1 ), a new acetonide derived polyacetylene ( 2 ) and a naturally occurring compound ( 3 ) from the plant kingdom along with sixteen known compounds ( 4 – 19 ). Their structures were elucidated by extensive NMR and MS analysis. This is the first report on the chemical constituents of G. theophrastifolium. Furthermore, compounds 12 , 13 , and 14 are reported for the first time from the family Asteraceae, while compound 9 is reported for the first time from the genus Gymnanthemum. Thus, the present results provide valuable insights to the chemophenetic knowledge of G. theophrastifolium, which is also discussed in this work.  相似文献   

14.
The corn cyst nematode Heterodera zeae was detected in soil from an organic maize field in northern Greece. In greenhouse studies, reproduction of H. zeae was detected on maize plants (Zeae mays) using soil high in organic matter; the field was under winter fallow at the time of sampling. Maize plants were grown in a greenhouse with soil from the affected field used as inoculum. Females appeared after six weeks incubation, and abundant cysts were present after 12 weeks. Morphological and molecular diagnosis confirmed the presence of H. zeae in the field. Cysts were identified on the basis of cyst shape and characteristics of the cyst terminal cone, including nature of fenestration, presence of bullae, cyst wall pattern, and fenestral diameter. Second-stage juveniles were identified by body and stylet length, the shape of stylet knobs, shape and length of the tail and hyaline tail terminus, and by the number of lateral lines. Molecular analysis included amplification of the ribosomal internal transcribed spacer regions (ITS 1&2 rDNA) 28S large ribosomal subunit (LSU) D2-D3 expansion segment, and partial 18S small ribosomal subunit (SSU). Restriction fragment length polymorphism (RFLP) of ITS rDNA exhibited several unique enzyme patterns that may be diagnostically useful for H. zeae. These findings are in agreement with prior analysis of H. zeae populations from the U.S. and India. Phylogenetic relationships inferred from ITS rDNA are congruent with previous analyses that placed H. zeae in a clade with H. turcomanica, H. salixophila and species of the Humuli group. Phylogenetic trees based upon heat shock protein (Hsp90) coding sequence were in general agreement with a prior study using the same marker. This study represents the first record of H. zeae in Greece and the second report of this nematode in Europe.  相似文献   

15.
The Mediterranean land snail genus Mastus (Beck, 1837) is highly divergent. Thirty-two Mastus species have been recorded throughout the genus range, and 23 of them are endemic to the islands of the Aegean Sea and mainland Greece. Of these, all 16 Mastus species reported from Crete are endemic to this island. A robust molecular phylogenetic framework based on mitochondrial and nuclear genes (1623 bp) allowed us to explore the temporal diversification pattern of lineages, using molecular clock approaches. Our results showed an initial radiation in the evolutionary history of the Cretan lineage, followed by a subsequent slowdown of lineage splitting rate. Using a dated major vicariant event of the Aegean area, we estimated the absolute time of the radiation event and proposed a biogeographic scenario accounting for the observed pattern. Additionally, we tried to infer the processes that led to the divergence of the Cretan Mastus species, by applying comparative methods in phylogenetically informated context. Overall, our results favoured a nonecological radiation scenario in the Cretan Mastus species due to an allopatric divergence of secondary sexual characters.  相似文献   

16.
《Palaeoworld》2023,32(3):555-572
The study examines the taxonomy of the newly excavated Nyctereutes material from Dafnero-3 (Greece) and the unpublished specimens from Varshets (Bulgaria). One cranium and a hemimandible from Dafnero-3 site are ascribed to the species Nyctereutes megamastoides, already known from Dafnero-1 and other Early Pleistocene sites of Greece. Two additional crania and a hemimandible from Dafnero-3, along with the Varshets dental material are attributed to N. tingi. This species was previously reported in the Early Pliocene Megalo Emvolon fauna of northern Greece but the record has been challenged and a review is provided. The new findings of Dafnero-3, and Varshets, extend the presence of N. tingi in southeastern Europe until the beginning of the middle Villafranchian and confirm the geographic expansion of the taxon towards West. Moreover, the co-existence of N. tingi and N. megamastoides in Dafnero-3 is reported for the first time in Europe. A paleoecological analysis based on the lower molar method agrees with the existing hypothesis of a more omnivorous N. megamastoides and a more carnivorous N. tingi ecomorph, which further justifies their local co-existence. Additionally, the quantitative analyses of N. tingi from Dafnero-3, and Varshets reveal a possible succession from N. tingi to N. vulpinus, as already supported by previous studies.  相似文献   

17.
The first Carboniferous conodonts studied from the Cares river section correspond to fifteen species and one subspecies from seven genera, some of them reported from the Picos de Europa Unit for the first time. The conodonts belong to several zones between the upper Tournaisian and the upper Serpukhovian-lower Bashkirian. Furthermore, the species Idiognathodus incurvus Dunn is reported for the first time in the Cantabrian Mountains and southern Europe, from upper Bashkirian or lower Moscovian beds.  相似文献   

18.
Growing conditions have been found out for the bacterium Arthrobacter GJM-I to produce a lytic enzyme system, which converts cells of the yeast Candida spec. H to protoplasts quickly and in a good yield. Estimating the activities of α-mannanase and β-glucanase we found out the optimal culture time to gain the lytic enzyme system from the culture filtrate. It was shown that radioactive labeling of the yeast cells makes it possible to estimate quantitatively the conversion to protoplasts and the simultaneous lysis. The obtained lytic enzyme system can substitute the snail cnzyme system which was used for cell conversion of Candida spec. H to protoplasts till now.  相似文献   

19.
《Journal of bryology》2013,35(3):493-498
Abstract

Weissia papillosissima Laz. is reported for the first time in Europe at different localities in the Iberian Peninsula. Previously it was known only from Tadhikistan in the former Soviet Union. The. species is described and illustrated and its distribution mapped and discussed.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号