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1.
Statistical population analyses have been carried out on so-calledOphrys arachnitiformis, partly sympatricO. sphecodes s. l. as well as on other species ofOphrys (O. holosericea, O. exaltata, O. apulica, O. cornuta, O. biscutella, O. bertolonii, O. bertoloniiformis.). Altogether 63 populations with 521 individuals were studied in regard to 54 morphological parameters. — It can be shown thatO. arachnitiformis is an extremely heterogeneous assemblage which includes taxa of most diverse origin, different degrees of stability and nomenclatorial rank. Only common trait is their very diverse relationships withO. specodes s.l.—The basionymO. arachnitiformis Gren. & Phil. refers to a colour variant ofO. sphecodes Mill. subsp.sphecodes only, and is not applicable to other segments of the assemblage.A late flowering, morphologically and biologically well isolated group of populations from southern France without any perceptible hybrid influence is established as a new species:Ophrys splendida Gölz & Reinhard. Populations from north and central Italy with distinct characters but hybrid influences fromO. holosericea/O. exaltata are calledO. tyrrhena Gölz & Reinhard.O. morisii, an endemic to Sardinia, represents an independent species of still obscure evolution. The hybrid interpretation ofO. catalaunica is statistically corroborated, but somewhat modified. For the remaining segments ofO. arachnitiformis investigated (from Castilia, Dalmatia, and the Monte Gargano) no formal taxonomic proposals are made, but some suggestions about their genesis are possible.
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2.
The author discusses the history of an unusual form ofPistacia lentiscus L. (referred to as var.chia (Desf. exPoiret) DC. on the basis of literature data and personal field observations on Chios island. As a result of incisions made on the trunk and stems the tree exudes a specific resinous gum called mastic. The production of mastic currently amounts to 160–170 tons per annum and plays an important role in the economy of the island constituting the main source of income for approx. 20 villages in the south of Chios. The history of mastic dates back 2500 years to the time ofHerodotus. The author points out that on the plantation only male individuals are cultivated; these have been selected over a long period based on mastic yield. As they represent a group of cultivated clones it would be preferable to consider them as a collective cultivar Chia.  相似文献   

3.
An electron microscopical investigation of the cell walls in young antheridia ofPolypodium crassifolium andPlatycerium alcicorne confirms the classical developmental model as postulated byStrasburger and byKny. The structure of the basal cell walls, both of the funnel cell and of the operculum, and especially the evidence of plasmodesmata in those walls, disprove the widely accepted interpretation presented 1951 byDavie.
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4.
Within the genusLoxonia Jack, currently regarded as monotypic, three species are recognized:L. hirsuta Jack (Sumatra, Mentawai-Islands, Java, Borneo, Anambas-Islands, Malay Peninsula),L. discolor Jack (Sumatra) andL. burttiana A. Weber, spec. nova (Borneo). [Key with English translation p. 203.] There is evidence thatL. discolor is the most primitive species within the genus, the two others being derived from it.
Teil V der Beiträge zur Morphologie und Systematik derKlugieae undLoxonieae (Gesneriaceae).  相似文献   

5.
Population variability ofOphrys holosericea (Burm. f.)Greut. subsp.holosericea (=O. fuciflora Crantz subsp.fuciflora) from near Vienna (Austria), and of subsp.maxima (Fleischm.)Greut. andO. cornuta Steven with intermediates from the Dalmatian island Hvar (Yugoslavia) was analysed and illustrated by scatter diagrams. A hybrid origin of these intermediates is suggested. Aspects of hybridization betweenO. holosericea agg. andO. scolopax agg. are discussed.
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6.
Microparacaryum (M. Pop. exH. Riedl)Hilger & Podlech is described as a new genus of theBoraginaceae-Cynoglosseae. It comprises the annual species hitherto included inParacaryum (DC.)Boiss. andMattiastrum (Boiss.)Brand. Distribution maps are given for all 3 genera.Microparacaryum consists of two species,M. salsum (Boiss.)Hilger & Podlech (M. s.) andM. intermedium (Fresen.)Hilger & Podlech (M. i.). ParticularlyM. i. is a very variable species, and most of the species formerly recognized belong here. Scattered all over the range of the genus, plants occur with nutlets exhibiting flat or incurved marginal wings, often in mixed populations. This fruit polymorphism is taxonomically treated by recognizing formae. In addition, the following new infraspecific taxa and combinations are described:M. i. var.intermedium formaparacaryoides Hilger & Podlech,M. i. var.stellatum (H. Riedl)Hilger & Podlech,M. i. var.stellatum formamattiastroides Hilger & Podlech,M. s. formamattiastroides Hilger & Podlech.
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7.
Ajuga piskoi Degen & Baldacci, hitherto known only from the type locality in Albania, has been found in Southern Yugoslavia. Two figures are presented. It is a rare and threatened plant species.
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8.
Arabis glabra (L.)Bernh. var.pseudoturritis (Boiss. & Heldr.)Fiori (till now treated as a separate Mediterranean species:Arabis pseudoturritis Boiss. & Heldr.) differs fromA. glabra var.glabra only in the larger ± pleurorhizal seeds with a ± conspicuous wing that are arranged in one row in each loculus of the (sometimes longer) pods, the pedicels of the siliquae being shorter than in var.glabra. These closely correlated characters are of little systematic relevance according to biometrical and statistical analyses of both taxa and their experimental hybrids. Furthermore, there is correspondence in pod septum anatomy and chromosome number (2n = 12). This, the lack of intrinsic crossing barriers and sympatric occurence (outside the Mediterranean area!) in North America confirm the classification of these taxa as varieties withinA. glabra. Obviously, the seed and fruit characters discussed, are of even less value as generic characters for a separate genus Turritis (comprising Turritisglabra L.).
Herrn Univ.-Prof. Dr.Hermann Merxmüller anläßlich der Vollendung seines 60. Lebensjahres gewidmet.  相似文献   

9.
InAchnanthes lanceolata pairing occurs by chance in regard to the arrangement of the mother cells, inA. minutissima it is accomplished selectively: contact at the sides occupied by the nucleus is favoured very strongly. In contrast toA. exilis, pairing inA. minutissima occurs by detachment of both partner cells from their stalks, whileA. lanceolata has no stalks at all. The isogamous gamete fusion inA. lanceolata should be understood as a modification of the anisogamous behavior inA. minutissima andA. exilis. For the three species the same constant orientation of the primary cell in relation to the substratum and to the mother thecae is characteristic. The first epivalva always is the raphe valve. InA. lanceolata in connection with the property of the primary cell possessing two chromatophores resp. pyrenoids instead of one, the transapical heteropolarity of the rapheless valve, a specific character, changes to isopolarity. It seems that a sort of induction from the pyrenoids towards the formation of the rapheless valve is at work. InA. lanceolata the pseudoraphe shows a structure hitherto unknown.A. lanceolata fo.ventricosa Hust. is to be eliminated. Var.rostrata (Östrup)Hust. is a good taxon; two new differential characters are found.
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10.
The remarkable diversity of fruits inValerianella andFedia is revealed by a comparative morphological and anatomical analysis. Characters are evaluated in regard to a new systematic grouping. The knowledge on dispersal biology is summarized and supplemented. Finally, salient features of fruit differentiation are discussed.
3. Teil der Publikationsserie Beiträge zur Systematik und Evolution vonValerianella undFedia (Valerianaceae) (vgl.Ernet 1977a, b).  相似文献   

11.
Two trisaccharide glycosides,p-trifluoroacetamidophenylethyl 3-O-(2-acetamido-2-deoxy--d-galactopyranosyl)-2-O-(-l-fucopyranosyl)--d-galactopyranoside andp-trifluoroa-cetamidophenylethyl 2-O-(-l-fucopyranosyl)-3-O-(-d-galactopyranosyl)--d-galactopyranoside, corresponding to the human blood group A and B determinants, were synthesized. A key fucosylgalactosyl disaccharide derivative was glycosylated with galactosaminyl or galactosyl donors, respectively. Dimethyl (thiomethyl)sulfonium tetrafluoroborate was used for thioglycoside activation in coupling reactions.  相似文献   

12.
The two characters used byBurtt (1974) to segregate the genusSchizoboea fromDidymocarpus, viz. terminal inflorescence and fruit splitting into 4 valves, have been studied in detail: (a) The terminal inflorescence represents a bracteate florescence (sensuTroll), that is an open thyrse, peculiar because of its only two extremely condensed internodes (basic internode + 1 following internode). Correspondingly, there are only two pairs of bracts from which the lower one only is capable to develop axillary partial florescences, i.e. pair-flowered cymes. Thus, the number of cymes is restricted to 2. Because of the condensed internodes, the inconspicuous bracts, and the densely aggregated flowers the two cymes simulate a unitary, terminal structure. By sympodial (± asymmetrically dichasial) linkage of shoot units, composed of an extended internode, a foliage leaf pair (from the axils of which the consecutive units arise) and the florescence,Schizoboea forms (polytelic) anthocladial shoot systems like some genera of the tribeKlugieae (incl.Loxonieae). (b) The fruit dehisces first loculicidally, then each valve splits into three portions (lateral rib and 2 semivalves). Moreover, the 4 placentae become isolated, thus the old fruit comprises 10 elements forming a loose fascicle.—The segregation ofSchizoboea fromDidymocarpus is supported. Whether the affinity is closer toSaintpaulia (as suspected byBurtt) ot toDidymocarpus, remains undecided: In regard to its shoot and inflorescence organization a morphological derivation is possible from both genera.
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13.
A more precise taxonomic concept ofE. hirtella and its infraspecific synonymy is presented. Its diploid nature (2n = 22) is confirmed. Within the European area ofE. hirtella five different races may be recognised: typical, brandisii, capitulata, Rofan and Bretagne. Taxonomic rank is not yet attributed to these races. The heterogeneous taxonomic assembly E. drosocalyx is disentangled. The type refers to products of hybrid introgression ofE. rostkoviana-characters (long glandular hairs) intoE. minima.
Former contributions of this series areEhrendorfer & Vitek (1984) andGreilhuber & al. (1984).  相似文献   

14.
Zusammenfassung Die Verwertung von Carnitin und Carnitinderivaten (O-Acylcarnitine, Carnitincarboxyl-derivate) und strukturverwandten Trimethylammoniumverbindungen (Betaine und Stickstoffbasen) durch Acinetobacter calcoaceticus wurde anhand des Wachstums und des quantitativen Nachweises der Metabolite untersucht. Der Stamm wuchs auf l-Carnitin, l-O-Acylcarnitinen und -Butyrobetain als jeweils einziger C-Quelle. Der Verbrauch dieser Verbindungen und das Wachstum korrelierten mit der Spaltung der C-N-Bindung und mit dem gebildeten Trimethylamin. d-Carnitin wurde metabolisiert, wenn als zusätzliche C-Quelle l-Carnitin im Nährmedium vorhanden war, oder wenn die Bakterien mit l-oder dl-Carnitin vorinkubiert worden waren. Mit d-Carnitin als einziger C-Quelle wuchsen die Bakterien jedoch nicht. Die Bakterien oxidierten Cholin zu Glycinbetain in Gegenwart einer zusätzlichen C-Quelle, Glycinbetain selbst wurde nicht assimiliert. In Hinsicht auf den Abbau quaternärer Stickstoffverbindungen besitzt Acinetobacter calcoaceticus im Vergleich zu anderen Carnitin-verwertenden Bakterienarten einen für ihn charakteristischen Stoffwechselweg.
Utilization of trimethylammonium-compounds by Acinetobacter calcoaceticus
The utilization of carnitine and carnitine derivatives (O-acylcarnitines, carnitine carboxylderivatives) and structure-related trimethylammonium-compounds (betaines and nitrogen-bases) by Acinetobacter calcoaceticus was studied by means of the control of growth and the quantitative detection of metabolites. The strain grew only on l-carnitine, l-O-acylcarnitines, and -butyrobetaine as the sole carbon sources. The utilization of these compounds and the growth correlated with the cleavage of the C-N bond and thereby with the formation of trimethylamine. d-Carnitine was metabolized, if an additional carbon source, like l-carnitine, was present in the incubation mixture, or if the bacteria were preincubated with l-or dl-carnitine, but no growth was observed on d-carnitine as the sole carbon source. The bacteria oxidized choline to glycinebetaine in the presence of additional carbon sources, glycinebetaine itself was not assimilated. With regard to the catabolism of quaternary nitrogen compounds Acinetobacter calcoaceticus shows a different pathway in comparison with other bacterial species metabolizing carnitine.
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15.
Veronica lycica Lehm. is a distinct, diploid member of theVeronica cymbalaria group, endemic in Lycia (S.W. Anatolia). Closely related is the newV. stamatiadae M. Fischer etW. Greuter which is also diploid and seems to be restricted to the small Greek island Ro close to the South coast of Lycia. The chromosome numbers for both species are reported for the first time (2n = 18).
Untersuchungen über den PolyploidkomplexVeronica cymbalaria agg., II. — Der erste Beitrag dieser Serie:Fischer (1975).  相似文献   

16.
The flowers ofValerianella andFedia are compared in regard to their morphology and anatomy. Characters are typified and utilized for an improved systematic grouping. Informations on flower development, flower and reproductive biology are summarized and supplemented. The phylogeny of several traits is discussed.
2. Teil einer Publikationsserie Beiträge zur Systematik und Evolution vonValerianella undFedia (Valerianaceae) (vgl.Ernet 1977a).  相似文献   

17.
The vascular pattern and its origin are described in connection with the differentiation of ground tissue in the shoot. Leaf arrangement ofClematis vitalba L. is decussate, and the vascular pattern appears rather simple at first: From internode to internode six strands—three from each leaf—alternate. About six internodes from the shoot apex, the pattern is completed by accessory strands which do not leave the axis and differentiate near the primary bark and exactly between the old strands. The formation of the acessory strands is not caused by the enlargement of the axis alone, because the balance between ground and vascular tissue is already regulated by the enlargement of the primary strands.
Zweiter Beitrag der Serie Die Sproßentwicklung vonClematis vitalba (Ranunculaceae) vgl. den ersten Beitrag:Schnettker (1976).  相似文献   

18.
A new genus,Aurantiosporium Piepenbring, Vánky & Oberwinkler (Ustilaginales), is proposed for the smut speciesUstilago subnitens Schröter & Hennings onScleria melaleuca Reichb. The soral morphology, teliospore development, the ultrastructure of the teliospore wall and teliospore germination ofAurantiosporium subnitens, studied on collections from Costa Rica, are described for the first time. The character set ofA. subnitens including intercellular teliospore development, spores in irregular groups and light coloured spore walls with numerous layers in TEM is neither known fromUstilago norCintractia nor any other smut species.Part 113 in the series Studies inHeterobasidiomycetes from the Botanical Institute, University of Tübingen.  相似文献   

19.
Five new species ofAnthemis sect.Anthemis from the Flora Iranica region are described:A. gillettii (subsect.Anthemis) from NW. Iraq and adjacent Iran is allied toA. damascena.—A. kurdica (subsect.Anthemis) also grows in Iraqi Kurdistan.—A. hamrinensis (subsect.Rascheyana; akin toA. plebeia) is distributed in the Jabal Hamrin region at the extreme outer margin of the Zagros chains.—A. kandaharica (subsect.Anthemis) andA. freitagii (subsect.Rascheyana) are distributed in Afghanistan.
Anschrift des Herausgebers: Hofrat Univ.-Prof. Dr.Karl Heinz Rechinger, Beckgasse 22, A-1130 Wien, Österreich.  相似文献   

20.
The thickened shoot bases ofNeoalsomitra podagrica carry spines of an undescribed nature: they represent morphologically phyllodes. A closed ring of sclerenchyma originating from the fusion of vascular bundle sheaths is responsible for the rigidity of these organs. Contrary to their cylindric structure these phyllodes are to be considered as bifacial. Between the region of phyllodial spines and foliage leaves there is a transition zone with petiole spines characterized by secondary loss of rudimentary leaf blades.
Herrn Prof. Dr.W. Leinfellner zum 65. Geburtstag gewidmet.  相似文献   

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