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1.
Abstract

On the presence of Hierochloë odorata (L.) Beauv. in Italy.—H. odorata has been found in an oligotrophic marsh in the Italian part of the Eastern Alps and therefore definitively confirmed for the flora of Italy. An extended population occurs at 1800 m above sea level near Misurina, in the Dolomites (province of Belluno). All preceding records of H. odorata for the Italian flora must be referred to H. australis (Schrader) R.&S. Differential characters and distribution of the two species are shortly discussed.  相似文献   

2.
Summary

The author describes a Sporobolus Poiretii (R. et S.) Hitchc. and Oenothera sinuata L. stand in the «Selva» (forest) of S. Rossore (near Pisa).

Earlier reports of these two adventive and perhaps naturalized species are mentioned.

The author discussues the critical and complex sistematic definition, nomenclature and sinonimy of Sporobolus Poiretii in connection with the nearly related species Sporobolus indicus R. Br.

The author prospects at the end how both Sp. Poiretii and Oe. sinuata can be inserted in the «Nuova Flora Analitica» of Italy, by Adriano Fiori.  相似文献   

3.
Abstract  The Lower Palaeozoic biostratigraphic records in the Alps are briefly reviewed and the result of a new study of the acritarch assemblage found by Sassi et al. (1984) in the greenschist facies black metapelites of the Southalpine metamorphic basement at Col di Foglia, and studied by Kalvacheva et al. (1986), is presented. The new  taxonomic and biostratigraphic study indicates a late Cambrian age, which is the oldest unquestionable, recently assessed, biostratigraphic dating of the entire Alps, as well as of the Italian peninsular. Keywords Alps, Southalpine metamorphic basement, Eastern Alps, Agordo, Acritarchs, Cambrian Subject codes: G17002  相似文献   

4.
The new species belongs toFestuca halleri agg. (F. ovina s. latiss.) and is diploid. Its habitat are alpine snow bed communities (Arabidetalia caeruleae) of the southern Alps, between the Brenta and Mt Cadria in the W and Mt Cavallo near Belluno in the E. Morphological, anatomical, epidermal, and ecological comparisons with related species suggest that it is closest to the vicariousF. rupicaprina in the N Alps.  相似文献   

5.
6.
《Journal of bryology》2013,35(2):209-212
Abstract

Encalypta brevipes Schljak. is reported in North America from north-western-most Oregon, United States; from Iceland; and in Europe from the Alps in southeastern France, and the High Tatra Mountains in Czechoslovakia. Encalypta brevicolla (B.S.G.) Bruch ex Aongstr. is reported from southernmost coastal Oregon, United States and east-central Scotland, Great Britain.  相似文献   

7.
《Journal of bryology》2013,35(2):339-346
Abstract

Type material is studied for six names of southern hemisphere Racomitria, viz. R. dustro-georgicum Par., R. amoenum (Broth.) Par., R. substenocladum Card., R. skottsbergii Card. et Broth., R. substenocladum fo. *nigrescens Card. et Broth., and R. austro-georgicum var. kranckii Riov. They are all placed as synonyms of R. sudeticum (Funck) Bruch et Schimp., which accordingly is bipolar. Racomitrium austro-sudeticum Broth. in Herz. belongs to the genus Grimmia.  相似文献   

8.
Extracts of bean (Phaseolus vulgaris L. cv. Greensleeves) cotyledons contained two abundant proteins: vicilin and phytohemagglutinin. Vicilin, a 6.9 S protein fraction at neutral pH, associated to an 18.0 S form at pH 4.5 and had 3 non-identical subunits with molecular weights (MW) of 52,000, 49,000 and 46,000. Phytohemagglutinin, a 6.4 S protein fraction, had 2 non-identical subunits with MW of 34,000 and 36,000. Phytohemagglutinin could be separated by isoelectrofocusing into a mitogenic and non-erythroagglutinating protein with a single subunit of MW=34,000, and a mitogenic and erythroagglutinating protein fraction which contained both subunits. Vicilin is apparently identical with the so called glycoprotein II (A. Pusztai and W.B. Watt, Biochim. Biophys. Acta 365, 57–71, 1970) and with globulin G1 (R.C. McLeester, T.C. Hall, S.M. Sun, F.A. Bliss, Phytochem. 2, 85; 1973), while phytohemagglutinin is identical with globulin G2 (McLeester et al., 1973). Since vicilin and phytohemagglutinin are internationally used names there is no need to introduce new names to describe P. vulgaris reserve proteins. Both proteins are catabolized in the course of seedling growth and are located in the protein bodies, indicating that they are reserve proteins. Vicilin isolated in its 18.0 S form from the cotyledons of young seedlings contains substantial quantities of smaller polypeptides, in addition the 3 original ones. We suggest that the presence of these small polypeptides represents partial breakdown of the vicilin prior to its complete catabolism.  相似文献   

9.
Background: Previous studies have indicated that several plant species had shown remarkable resistance to Pleistocene climate changes and survived the Last Glacial Maximum in scattered ice-free refugia within the European Alps and peripheral areas nearby. The ‘Expansion–Contraction’ model has been proposed to describe the responses of organisms to Pleistocene climate change. Nevertheless, the timing and extent to which species were affected by Quaternary glaciations remain uncertain.

Aims: To test whether the ‘Expansion–Contraction’ model appropriately describes plant distribution responses to Pleistocene climate change in the Western Alps.

Methods: We employed two Bayesian coalescent-based methods on plastid DNA sequences to infer the demographic histories of Ranunculus kuepferi, R. glacialis, Biscutella laevigata, Saxifraga oppositifolia, Primula allionii, P. marginata, Silene cordifolia and Viola argenteria.

Results: R. kuepferi conformed to the ‘Expansion–Contraction’ model, while other species did not. For example, P. allionii showed an alarming population decline during the Middle-Late Pleistocene.

Conclusions: The application of Bayesian coalescent-based methods to plastid DNA data offers useful insights into plant demography as a function of palaeoclimatic events. Our findings favour an idiosyncratic response of plant species in the Western Alps to Pleistocene climate change.  相似文献   

10.
Currently, 119 high resolution structures of Thermotoga maritima proteins have been determined by the Joint Center for Structural Genomics (JCSG, www.jcsg.org). Sixty-seven of these were solved using the first implementation of the multi-tiered crystallization strategy at the JCSG for the efficient crystallization of large numbers of protein targets. Previously, we reported the analysis of all proteins crystallized using this multi-tiered strategy [Lesley, S.A. et al. (2002) Proc. Natl. Acad. Sci. USA 99, 11664–11669; Page, R. et al. (2003) Acta Crystallogr. D Biol. Crystallogr. 59, 1028–1037]. Here, we extend the analysis and describe the crystallization characteristics of those proteins that produced diffraction quality crystals, ultimately resulting in high resolution structures. First, we found that over 77% (52) of the crystals used for structure determination were produced directly from high-throughput coarse screens, indicating that less than one quarter of the crystals (15) required fine screening. In addition, as observed for the proteome screen [Page, R. et al. (2003) Acta Crystallogr. D Biol. Crystallogr. 59, 1028–1037], the majority of conditions that produced crystals for natively expressed proteins, whose structures have been determined, were distinct from those of their more extensively purified and selenomethionine-labeled counterparts. Finally, 99% of the proteins whose structures were solved crystallized in conditions contained in the JCSG Minimal Core Screen [Page, R. et al. (2003) Acta Crystallogr. D Biol. Crystallogr. 59, 1028–1037; Page, R. and Stevens, R.C. (2004) Methods 34, 373–389], a set of 67 conditions previously identified as those most likely to produce crystals of a diverse set of proteins, confirming its success for rapid identification of proteins with a natural propensity to crystallize.  相似文献   

11.
One of the limitations of stochastic, linear compartmental systems is the small degree of variability in the contents of compartments. S. R. Bernard's (1981) urn model (S. R. Bernardet al., Bull. math. Biol. 43, 33–45.) which allows for bulk arrivals and departures from a one-compartment system, was suggested as a way of increasing content variability. In this paper, we show how the probability distribution of the contents of an urn model may be simply derived by studying an appropriate set of exchangeable random variables. In addition, we show how further increases in variability may be modeled by allowing the size of arrivals and departures to be random. Supported by NSF Grant No. MCS 8102215-01.  相似文献   

12.
Abstract

Horsfall, J. G. (Ed.): Annual Review of Phytopathology. Vol. 4. VII + 423 S. Palo Alto, 1966: Annual Reviews, Inc. Leinen, 9,00 $. Reviewed by K. Naumann.

Gregory, P. H. und Monteith, J. L. (Ed.): Airborne microbes. Seventeenth Symposium of the Society for General Microbiology held at the Imperial College, London April 1967. XII + 385 S., mit Abb. u. Tab. London, 1967: Cambridge University Press, Leinenrücken, 75 s. Reviewed by H. J. Müller.

Raper, J. R.: Genetics of sexuality in higher fungi. VIII + 283 S., mit Abb. u. Tab., New York, 1966: The Ronald Press Company, Leinen, 12,00 $. Reviewed by M. Schmiedeknecht.

Albrecht, F. O.: Polymorphisme phasaire et biologie des acridiens migrateurs. X + 194 S., 52 Abb. Paris, 1967: Masson et Cie, Éditeurs, karton., 50 F. Reviewed by R. Fritzsche.

Wigglesworth, V. B.: Insect physiology. VII + 134 S., 12 Abb., London, 1966: Methuen &; Co Ltd., brosch., 10 s 6 d. Reviewed by G. Schäller.

Machlis, L. (Ed.): Annual Review of Plant Physiology. Vol. 18. VIII + 480 S., mit Abb. u. Tab., Palo Alto, Ca., 1967: Annual Reviews, Inc., Leinen, 9,00 $. Reviewed by H. Wolffgang.

Newton, B. A. und Reynolds, P. E. (Ed.): Biochemical studie of antimicrobial drugs. (Sixteenth symposium of the Society for General Microbiology held at the Royal Institution, London, April 1966). X + 349 S., mit Abb. u. Tab., London, 1966: Cambridge University Press, Halbleinen, 60 s. Reviewed by H. J. Müller.

Pilet, P.-É.: La cellule, structure et fonctions. 406 S., 310 Abb.; 32 ganzs. Abb., Paris 1966: Schwarz-Weiß-Tafeln. Masson et Cie, Editeurs, brosch. 38 F. Reviewed by K. Schmelzer.

Ciba (Ed.): Dimecron 257 S. Basle, Switzerland, 1967: P.O. Box — CIBA — Kunststoff Reviewed by Horst Beitz.

Bellamy, L. J.: Ultrarot-Spektrum und chemische Konstitution. 2. Auflage, 325 S., 11 Abb., 23 Tab. Darmstadt, 1966: Dr. Dietrich Steinkopff Verlag, kart., 28,— DM Reviewed by Volker Müller.

Bahr, G. F.; Zeitler, E. H. (Ed.): Quantitative electron microscopy. 1965, VIII + 605 (1340) S., mit Abb. u. Tab., Leinen, 16,00 $, Baltimore (Md.), The Williams &; Wilkins Company. Reviewed by H. B. Schmidt.  相似文献   

13.
Abstract: The susceptibility to high temperature‐induced photoinhibition was investigated in leaves of two high mountain plant species, S. alpina and R. glacialis. In both species, PSII was similarly photoinactivated at 38 °C in the light. However, recovery from damage was much faster in S. alpina and depended on protein synthesis. In contrast, recovery was independent from protein synthesis in R. glacialis. Heat‐induced photoinactivation in both species was accompanied by: (1) a decrease in relative photosynthetic electron transport rates, (2) an increase in non‐photochemical chlorophyll fluorescence quenching, (3) a strong accumulation of zeaxanthin, (4) a marked decrease in soluble carbon metabolites and (5) an increase in lipid metabolism products, which was more pronounced in R. glacialis than in S. alpina. These results indicate that carbon assimilation was inhibited and that membranes were affected. Lipid peroxidation and possible membrane disintegration might limit the repair of damaged PSII in R. glacialis, while S. alpina appears to be protected by carotenoids and antioxidants. A marked decrease in α‐tocopherol content and an increase in reduced ascorbate indicated lipid peroxide scavenging activity in S. alpina. When zeaxanthin synthesis was impaired by DTT, photoinhibition increased and α‐tocopherol accumulated in R. glacialis. The increased susceptibility of R. glacialis leaves to light‐induced photoinhibition after growth at moderate temperature (Streb et al., 2003a) and the inability to repair heat‐induced damage might limit the distribution of R. glacialis to lower altitudes in the Alps.  相似文献   

14.
Summary The theoretical power density spectrumS(f) of ion current noise is calculated from several models of the sodium channel gating mechanism in nerve membrane. Sodium ion noise experimental data from the frog node of Ranvier [Conti, F.,et al. (1976),J. Physiol. (London) 262:699] is used as a test of the theoretical results. The motivation for recent modeling has been evidence for a coupling between sodium activation and inactivation from voltage clamp data. The two processes are independent of one another in the Hodgkin and Huxley (HH) model [Hodgkin, A.L., Huxley, A.F. (1952),J. Physiol. (London) 117:500] The noise data is consistent with HH, as noted by Contiet al. (1976). The theoretical results given here appear to indicate that only one case of coupling models is also consistent with the noise data.  相似文献   

15.
Abstract

TRINIA DALECHAMPII in the Illyric component of the Flora of the Apuan Alps. — On a mountaintop in the Apuan Alps, the author found Trinia dalechampii, an Illyric entity known until now in Ytaly only in the central and southern Apennines. He also indicates that a Greco-Apennine Oligo-Miocene bridge was the probable migration-route of this species and likewise of the Illyric entities of the Apennines.  相似文献   

16.
Molecular data obtained by a procedure for extracting PCR-amplifiable nuclear and chloroplast DNA from old and formalin-fixed red algal herbarium specimens were used to elucidate problems in the systematics of Pacific Gigartinaceae. Correspondence between nucleotide sequences of the internal transcribed spacer 1 region or the RUBISCO spacer from type specimens and modern collections supports the following conclusions. (1) The type of Fucus cordatus Turner, now Iridaea cordata (Turner) Bory, came from the southern hemisphere (probably from Isla de los Estados, Argentina) rather than from Banks Island, B.C., Canada. (2) The type of Iridaea heterocarpa P. et R. [Mazzaella heterocarpa (P. et R.) Fred.] represents the tetrasporangial phase of a species of Chondrus, possibly C. crispus Stackh. (3) The types of Iridaea lilacina P. et R., I. phyllocarpa P. et R., and Iridophycus furcatum S. et G. represent a single species from Alaska, Mazzaella phyllocarpa (P. et R.) Perest., currently but incorrectly called M. heterocarpa. (4) The type of Iridophycus oregonum Doty represents the tetrasporangial phase of the species from southern Alaska to southern California known incorrectly as M. heterocarpa. (5) Mazzaella splendens (S. et G.) Fred. is more closely related to M. linearis (S. et G.) Fred. than it is to M. flaccida (S. et G.) Fred. (6) Iridophycus coriaceum S. et G. is conspecific with M. splendens, whereas Rhodoglossum coriaceum E.Y. Dawson is an independent species: Mazzaella coriacea (E.Y. Dawson) Hughey. (7) Iridaea cornucopiae P. et R. is conspecific with Mazzaella laminarioides (Bory) Fred., and the type probably came from Chile rather than from the North Pacific. (8) Plants attributed to Iridaea cornucopiae in Pacific North America are referable to Mazzaella parksii (S. et G.) comb. nov. (9) Rhodoglossum parvum G. M. Smith et Hollenb. is an independent species: Mazzaella parva (G. M. Smith et Hollenb.) comb. nov. (10) Grateloupia squarrulosa S. et G., Grateloupia johnstonii S. et G., and Gigartina pectinata E.Y. Dawson represent a single species: Chondracanthus squarrulosus (S. et G.) comb. nov.  相似文献   

17.
Summary The molecular sizes of F1 me resistance plasmids from strains of Salmonella typhimurium, S. wien and S. typhi were within the range 87.9–102.6×106 daltons. DNA reassociation studies indicated that the plasmids from these hosts had at least 80% of their nucleotide sequences in common. A high proportion of F1 me plasmids cannot mediate their own transfer. The non-autotransferring property of such plasmids is the result of DNA deletion; a non-autotransferring F1 me plasmid was about 10×106 daltons shorter than autotransferring representatives of the group, and its DNA showed 100% homology with them. Plasmids of the F1 me group are incompatible with the F factor and with F1R factors. F1 me plasmids are incompatible with the fi + MP10 plasmid of S. typhimurium, whereas F and F1 factors are compatible with MP10 (Anderson et al., 1977). There was no significant DNA homology between members of the F1 me group and MP10, and these plasmids may share only a small region of DNA responsible for their incompatibility. The F1 me R factors examined had 29–37% DNA homology with the F factor, and 50–58% homology with the F1 resistance plasmid, R162. Molecular examination therefore supports the genetic differentiation of members of the F1 me group from other F-like plasmids. Both types of investigation can thus be used in epidemiological studies of bacterial strains carrying resistance or other plasmids.  相似文献   

18.
Polymerase chain reaction primers based on the ureC gene are described for use in detecting diverse groundwater urea-hydrolyzing bacteria. Six degenerate primers were designed and evaluated for their ability to detect the gene encoding the large catalytic subunit of urease, ureC. Five combinations of these primers were tested pair-wise and displayed an overlapping detection range for bacterial isolates. Pair L2F/L2R exhibited the greatest detection range for described bacterial species and for bacterial isolates from groundwater samples belonging to the bacterial divisions Firmicutes, Actinobacteria, and the α , β , and γ subdivisions of Proteobacteria. Primers L2F/L2R exhibited a greater detection range than previously described ureC-specific primers, and amplified novel ureC sequences from groundwater isolates in the genera Hydrogenophaga, Acidovorax, Janthinobacterium, and Arthrobacter. A comparative phylogenetic analysis of ureC and 16S rRNA genes was performed to determine the utility of groundwater ureC sequence information as a phylogenetic marker for ureolytic species. Our results were consistent with previous analyses of urease genes which demonstrated that the ureC gene has undergone lateral transfer and is not a robust phylogenetic marker. However, the ureC-specific primers, L2F/L2R, demonstrate a broad detection range for ureolytic species, and can serve to enhance functional diversity analyses of ureolytic bacteria.  相似文献   

19.
Low-molecular-weight glutenin subunits (LMW-GS) have great effect on wheat processing quality, but were numerous and difficult to dissect by SDS-PAGE. The development of functional markers may be the most effective way for a clear discrimination of different LMW-GS genes. In the present study, three different approaches were used to identify SNPs of different genes at Glu-D3 and Glu-B3 loci in bread wheat for the development of six STS markers (3 for Glu-D3 and 3 for Glu-B3 genes) that were validated with distinguished wheat cultivars. Firstly, seven LMW-GS gene sequences ( AY585350, AY585354, AY585355, AY585356, AY585349, AY585351 and AY585353 ) from Aegilops tauschii, the diploid donor of the D-genome of bread wheat, were chosen to design seven pairs of AS-PCR primers for Glu-D3 genes. By amplifying the corresponding genes from five bread wheat cultivars with different Glu-D3 alleles (a, b, c, d and e) and Ae. tauschii, a primer set, S13F2/S13R1, specific to the gene AY585356, was found to be positive to cultivars with alleles Glu-D3c and d. Nevertheless, the other five pairs of primers designed from AY585350, AY585349, AY585353, AY585354 and AY585355, respectively, did not produce specific PCR products to the cultivars tested. Secondly, all the PCR products from the five primer sets without specific characteristics were sequenced and an SNP from the gene AY585350 was detected in the cultivar Hartog, which resulted in the second STS marker S1F1/S1R3 specific to the allelic variant of AY585350. Thirdly, three Glu-D3 sequences (AB062851, AB062865 and AB062872) and three Glu-B3 sequences (AB062852, AB062853 and AB062860) defined by Ikeda et al. (2002) were chosen to query wheat EST and NR databases, and DNA markers were developed based on the putative SNPs among the sequences. Using this approach, four STS markers were developed and validated with 16-19 bread wheat cultivars. The primer set T1F4/T1R1 was also a Glu-D3 gene-specific marker for AB062872, while T2F2/T2R2, T5F3/T5R1 and T13F4/T13R3 were all Glu-B3 gene specific markers for AB062852, BF293671 and AY831800, respectively. The chromosomal locations of the six markers were verified by amplifying the genomic DNA of Ae. tauschii (DD), T. monococcum (AA) and T. turgidum (AABB) entries, as well as Chinese Spring and its group 1 chromosome nulli-tetrasomic lines. The results are useful to discriminate the corresponding Glu-D3 and Glu-B3 genes in wheat breeding programs.  相似文献   

20.
Aim The aim of this study was to test hypotheses regarding some of the main phylogeographical patterns proposed for European plants, in particular the locations of glacial refugia, the post‐glacial colonization routes, and genetic affinities between southern (alpine) and northern (boreal) populations. Location The mountains of Europe (Alps, Balkans, Carpathians, Central Massif, Pyrenees, Scandinavian chain, Sudetes), and central European/southern Scandinavian lowlands. Methods As our model system we used Pulsatilla vernalis, a widely distributed European herbaceous plant occurring both in the high‐mountain environments of the Alps and other European ranges and in lowlands north of these ranges up to Scandinavia. Based on a distribution‐wide sampling of 61 populations, we estimated chloroplast DNA (cpDNA) variation along six regions using polymerase chain reaction–restriction fragment‐length polymorphisms (PCR–RFLPs) (trnH–trnK, trnK–trnK, trnC–trnD, psbC–trnS, psaA–trnS, trnL–trnF) and further sequencing of trnL–trnF and trnH–psbA. In addition, 11 samples of other European species of Pulsatilla were sequenced to survey the genus‐scale cpDNA variation. Results Eleven PCR–RFLP polymorphisms were detected in P. vernalis, revealing seven haplotypes. They formed two distinct genetic groups. Three haplotypes representing both groups dominated and were widely distributed across Europe, whereas the others were restricted to localized regions (central Alps, Tatras/Sudetes mountains) or single populations. Sequencing analysis confirmed the reliability of PCR–RFLPs and homology of haplotypes across their distribution. The chloroplast DNA variation across the section Pulsatilla was low, but P. vernalis did not share haplotypes with other species. Main conclusions The genetic distinctiveness of P. vernalis populations from the south‐western Alps with respect to other Alpine populations, as well as the affinities between the former populations and those from the eastern Pyrenees, is demonstrated, thus providing support for the conclusions of previous studies. Glacial refugia in the Dolomites are also suggested. Isolation is inferred for the high‐mountain populations from the Tatras and Sudetes; this is in contrast to the case for the Balkans, which harboured the common haplotype. Specific microsatellite variation indicates the occurrence of periglacial lowland refugia north of the Alps, acting as a source for the post‐glacial colonization of Scandinavia. The presence of different fixed haplotypes in eastern and western Scandinavia, however, suggests independent post‐glacial colonization of these two areas, with possible founder effects.  相似文献   

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