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1.
Nyananyo B. L. (1988): The systematic significance of seed morphology and anatomy in thePortulacaceae (Centrospermae).—Folia Geobot. Phytotax., Praha, 23: 275–279.—The seeds of 115 species in eighteen genera of the familyPortulacaceae were examined with the scanning electron microscope. Longitudinal sections of seeds of representatives of all the genera were examined with the light microscope. Two broad groups based on shape of the seeds, ornamentation of the external surface of their testa, and the position of the embryo relative to the endosperm were recognised. The first group comprising three genera:Anacampseros L.,Grahamia Gillies andTalinopsis A. Gray, have seeds which are pyriform with wings and trichomes, and an embryo that is more or less parallel to the endosperm, while the second of fifteen genera:Calandrinia H.B.K.,Calyptridium Nuttall,Calyptrotheca Gilg,Ceraria Pearson etStephens,Claytonia L.,Lenzia Philippi,Lewisia Pursh,Lyallia Hooker fil.,Montia L.,Portulaca L.,Portulacaria Jacquin,Silvaea Philippi,Talinella Baillon,Talinum Adanson, andWangerinia Franz, are reniform without wings and with an embryo that is horse-shoe shaped around the endosperm.  相似文献   

2.
Palaeoecological reconstructions from the region of southwestern Bulgaria were used for inferring the human impact on the vegetation and landscape during the last 8 millennia. They are based on data from pollen analyses of lakes and peat-bogs, plant macrofossils, archaeobotanical finds and radiocarbon dating. During the early Holocene, after 7900?cal. b.p. (5950?cal. b.c.) the climate changed to cooler summers, milder winters and higher precipitation resulting in the formation of a coniferous belt dominated by Pinus sp. and Abies alba. These favorable environmental pre-conditions had a positive influence on the Neolithisation of the Balkans after the 8200?cal. b.p. (6250?cal. b.c.) cold event, which caused drought in the Eastern Mediterranean. Direct evidence from wood charcoal records from the Neolithic settlement layers in the study area shows a slight modification of the surrounding woodlands and an increase of the light-demanding components, probably expressed through larger forest border zones and thinning out of the wood stands. The increase in the number of settlements in the valleys of southwestern Bulgaria intensified the human activity visible in the palaeobotanical record from 6950?cal. b.p. (5000?cal. b.c.) onwards. Between ca. 5700–5100?cal. b.p. (3800–3200?cal. b.c.) signs of anthropogenic influence on the vegetation are virtually absent. The intensity of human impact increased notably after 3200?cal. b.p. (1400–1250?cal. b.c., approx. Late Bronze Age), documented by a rise of pollen anthropogenic indicators. The final transformations in the natural forest cover after 2750?cal. b.p. (800?cal. b.c. onset of the Iron Age) marked the reduction of the coniferous forests dominated by Abies alba and Pinus sp. and the expansion of Fagus sylvatica and Picea abies. These vegetation changes are contemporaneous with increase of the palaeofire activities and the next peak of anthropogenic indicators. The changes in the landscape during the Roman period and the medieval period reflect regional environmental features and were forced by the diversification of anthropogenic activity.  相似文献   

3.
Bottle gourd (Lagenaria siceraria (Molina) Standl.) is accepted as typical ‘New World’ cultivated economic plant. Currently, two subspecies are known: L. siceraria ((Molina) Standl.) ssp. siceraria has an African origin, whilst ssp. asiatica is recognized to be originating from Asian territories. It only seldom appears in European archaeological contexts, however finds from the Roman period appear sporadically. Part of a Late Middle Age (14th–15th century) settlement was excavated near the town of Pócspetri (SE Hungary) and one of the refuse pits contained waterlogged remains of several dozen dicot leaves and small sized branches (e.g. Populus sp.). In addition an entire dog skeleton and an apparently 10 cm by 7 cm bottle gourd pericarp fragment were also found in a well-preserved pot. This fortunate recovery accounts for the first evidence of bottle gourd in the archaeobotanical record of Hungary and Eastern Europe. Due to its favourable preservation not only precise morphological analysis could be undertaken, but ancient DNA (aDNA) extraction, PCR amplification and sequencing were used to identify more closely its possible origin and taxonomic relations. Different diagnostic phytolith morphotypes of the pericarp were matched to reference material phytolith assemblages. The macro-archaeobotanical record of the feature reflects the botanical elements of the natural environment of this medieval site and places the unique bottle gourd find in context.  相似文献   

4.
In the years 1976–1981 we studied chromosome counts and karyotypic formulae of the following 29 species of plants from 41 localities (of these 6 from Bohemia, 32 from Moravia, 3 from Slovakia):Batrachium baudotii (Godron) F. W. Schultz,Chenopodium rubrum L.,C. polyspermum L.,C. murale L.,C. ficifolium Sm.,C. opulifolium Schrader ex DC. inLam. et DC.,C. strictum Roth [subsp.strictum, subsp.glaucophyllum (Aellen)Aellen inJust etAellen, subsp.striatiforme Uotila],Arenaria grandiflora L.,Illecebrum verticillatum L.,Spergula morisonii Boreau inDuchartre,Spergularia marginata (DC. inLam. et DC.)Kittel S. marina (L.)Griseb.,S. rubra (L.) J. etC. Presl,Silene conica L.,Sisymbrium loeselii L.,S. volgense Bieb. exE. Fourn.,S. orientale L. [subsp. orientale, subsp.macroloma (A. Pomel)Dvo?ák],S. officinale (L.)Scop.,Descurainia sophia (L.)Webb exPrantl inEngler etPrantl,Nasturtium officinale R. Br. inAiton,Barbarea arcuata (Opiz inPresl J. et C.)Reichenb.,Lunaria annua L.,Soldanella montana Willd.,S. carpatica Vierh. inUrban etGraebner,Lotus tenuis Waldst. etKit. exWilld.,L. uliginosus Schkuhr,Trigonella monspeliaca L.,Geranium sibiricum L.,Lactuca tatarica (L.)C. A. Meyer.  相似文献   

5.
The present study deals with five genera of hepatics in Africa, Isotachis Mitt., Anastrophyllum (Spruce) Steph., Tritomaria Schiffn. ex Loeske, Gymnocoleopsis (Schust.) Schust. and Lophozia (Dum.) Dum. All African populations of the genus Isotachis Mitt. are considered to be one species, I. aubertii (Schwaegr.) Mitt. Four species of Anastrophyllum (Spruce) Steph. (s.l.), A. auritum (Lehm.) Steph., A. piligerum (Nees) Spruce, A. subcomplicatum (Lehm. et Lindenb.) Steph. and A. minutum (Schreb.) Schust., and two species of Tritomaria Schiffn. et Loeske, T. camerunensis S. Arnell and T. exsecta (Schrad.) Schiffn. ex Loeske occur in Africa. Gymmocoleopsis multiflora (Steph.) Schust. represents a genus and species hitherto unreported for the African flora. Finally, five Lophozia (Dum.) Dum. species, L. argentina (Steph.) Schust., L. capensis S. Arnell, L. decolorans (Limpr.) Steph., L. hedbergii S. Arnell and L. tristaniana (S. Arnell) Váňa, are reported from central and southern Africa; two of these (L. argentina (Steph.) Schust. and L. decolorans (Limpr.) Steph.) represent the first reports from Africa.  相似文献   

6.
The Tethyan genus “Belemnopsis” of authors, notBayle 1878, includes 110–120 Bajocian to Hauterivian belemnite species and subspecies from Europe and the southern hemisphere. Its type species,Belemnites sulcatus Miller 1826 from the Callovian to Oxfordian of England, belongs to the Boreal belemnite genusLagonibelus Gustomesov 1956, since Phillips selected a lectotype for it in 1870. But the subsequent designation of the type species byDouvillé in 1879 is invalid according to Art. 67 (h) ICZN, and consequentlyBelemnopsis Bayle gets a nomen dubium. It is also a homonym ofBelemnopsis Edwards inGray 1849, and has, therefore, to be replaced byPachybelemnopsis Riegraf 1980, a junior subjective synonym, the family Belemnopseidae Naef 1922 by MesohibolitidaeNerodenko 1983, and the suborder BelemnopseinaJeletzky 1965 by PachybelemnopseinaRiegraf inRiegraf et al. 1998.  相似文献   

7.
Four species of the genusBrachysporium Sacc. emend.Mason etHughes are treated in this paper from Czechoslovakia:B. nigrum (Link)Hughes,B. obovatum (Berk.)Sacc. and two new species,B. abietinum Hol.-Jech. andB. brevius Hol.-Jech.  相似文献   

8.
To better understand the response of forest vegetation to climate and fire regimes with reference to human activities over the last deglacial period in the Aso Caldera, central Kyushu, southwestern Japan, a 33.9 m long sediment core was examined in order to reconstruct the vegetational and fire history using pollen and charcoal analyses. The results show that a cool temperate broad-leaved deciduous forest, dominated by Quercus (deciduous oaks) with Carpinus and Fagus, prevailed in the Aso Valley from ca. 14.6 ka cal. b.p., indicating warming since the last glacial period. The landscape was presumably covered by a mosaic of deciduous Quercus forests and terrestrial Artemisia communities. Around 12.8–11.7 ka cal. b.p., Quercus dominated the forest and fires occurred frequently. Co-expansion of distinctive UlmusZelkova and CeltisAphananthe forests coupled with a progressive retreat of Quercus in the early Holocene could reflect a strengthening of the East Asian summer monsoon under mild and humid climate conditions. Around 8 ka cal. b.p., significant increases in Cyclobalanopsis (evergreen oaks), Castanopsis/Castanea and Podocarpus indicate a further warming, in particular an increased winter temperature. Warm temperate lucidophyllous forests, dominated by Cyclobalanopsis, flourished after 7.3 ka cal. b.p., probably corresponding to the “Holocene Climatic Optimum” interval. Progressive expansion of Quercus at the expense of Cyclobalanopsis began around 6.4 ka cal. b.p. and paralleled an increase in charcoal until ca. 4.8 ka cal. b.p.; this could be evidence of fire disturbance induced by the early-middle Jomon people. The disturbed evergreen forest experienced a temporary recovery but then opened again from 3.6 ka cal. b.p. due to extensive fire deforestation, as suggested by the high charcoal levels during this time. Human exploitation and buckwheat (Fagopyrum) agriculture may have contributed to the opening of the forest, which allowed secondary forests (primarily Pinus and Quercus) and herbaceous communities (mainly Poaceae) to spread. These results are discussed in comparison with other high-resolution pollen data from western Japan to better elucidate the vegetation and fire history over the last deglacial in the Aso Caldera.  相似文献   

9.
The sphinctozoid sponge generaFania Senowbari-Daryan 1990 andSpica Termier &Termier 1977 are preoccupied.Fania is replaced byFanthalamia nom. nov. andSpica by the younger synonymFistulispongia Termier &Termier 1977. The invalid subfamily name FaniinaeSenowbari-Daryan 1990 is replaced by Fanthalamiinae n. subfam. The invalid family and subfamily names SpicidaeTermier &Termier 1977 and SpicinaeSenowbari-Daryan 1990 respectively are replaced by FistulispongiidaeTermier atTermier 1977 and FistulispongiinaeSenowbari-Daryan 1990. The generaWaagenium de Laubenfels 1957 andCatubria Merla 1931 were previously overlooked.Waagenium DeLaubenfels 1957 is a younger synonym ofColospongia Laube 1865. The position ofCatubria Merla 1931 is uncertain. Most probablyCatubria is an alga.  相似文献   

10.
In this study, extremely halophilic and moderately thermophilic microorganisms from a hypersaline microbial mat were screened for their ability to produce antibacterial, antidiatom, antialgal, and quorum-sensing (QS) inhibitory compounds. Five bacterial strains belonging to the genera Marinobacter and Halomonas and one archaeal strain belonging to the genus Haloterrigena were isolated from a microbial mat. The strains were able to grow at a maximum salinity of 22–25 % and a maximum temperature of 45–60 °C. Hexanes, dichloromethane, and butanol extracts from the strains inhibited the growth of at least one out of nine human pathogens. Only butanol extracts of supernatants of Halomonas sp. SK-1 inhibited growth of the microalga Dunaliella salina. Most extracts from isolates inhibited QS of the acyl homoserine lactone producer and reporter Chromobacterium violaceum CV017. Purification of QS inhibitory dichloromethane extracts of Marinobacter sp. SK-3 resulted in isolation of four related diketopiperazines (DKPs): cyclo(l-Pro-l-Phe), cyclo(l-Pro-l-Leu), cyclo(l-Pro-l-isoLeu), and cyclo(l-Pro-d-Phe). QS inhibitory properties of these DKPs were tested using C. violaceum CV017 and Escherichia coli-based QS reporters (pSB401 and pSB1075) deficient in AHL production. Cyclo(l-Pro-l-Phe) and cyclo(l-Pro-l-isoLeu) inhibited QS-dependent production of violacein by C. violaceum CV017. Cyclo(l-Pro-l-Phe), cyclo(l-Pro-l-Leu), and cyclo(l-Pro-l-isoLeu) reduced QS-dependent luminescence of the reporter E. coli pSB401 induced by 3-oxo-C6-HSL. Our study demonstrated the ability of halophilic and moderately thermophilic strains from a hypersaline microbial mat to produce biotechnologically relevant compounds that could be used as antifouling agents.  相似文献   

11.
Dersechste Beitrag aus der Serie der vorbereiteten Studien über die SubfamilieJungermannioideae (Jungermanniaceae, Hepaticae) enthält die taxonomische Bearbeitung des Subg.Solenostoma (Mitt.)Amak. (GattungJungermannia L. emend.Dum.) in Europa (inkl. Kaukasus und Kleinasien) und Nordamerika. Im genannten Gebiet kommen 10 Arten vor, u. zw.J. caespiticia Lindenb.,J. caucasica Váňa,J. confertissima Nees,J. gracillima Sm.,J. handelii (Schiffn.)Amak.,J. jenseniana Grolle,J. lignicola (Schiffn.)Grolle,J. pyriflora Steph.,J. rubra Gott. exUnd. undJ. sphaerocarpa Hook. Die ArtJ. confertissima Nees (bisher alsSolenostoma levieri (Steph.)Steph. bezeichnet) gehört zu der SektionDesmorhiza Amak., alle anderen Arten gehören zu der SektionSolenostoma.  相似文献   

12.
Six species of the genusBactrodesmium M. C. Cooke are described in this paper from Czechoslovakia:B. betulicola M.B. Ellis,B. obovatum (Oudemans) M.B. Ellis,B. spilomeum (Berk. etBr.)Mason etHughes including three new speciesB. globosum Hol.-Jech.,B. pyriforme Hol.-Jech. andB. submoniliforme Hol.-Jech.  相似文献   

13.
Observations on parasites were made during a study of the following rice stem-borers in Sarawak (Malaysian Borneo):Tryporyza incertulas (Walker),T. innotata (Walker),Chilo suppressalis (Walker)C. auricilia (Dudgeon), andSeamia inferens (Walker). Egg-parasitism was often high, but that of the larval and pupal stages generally very low. Between 40–80% of theTryporyza eggs were parasitised byTelenomus rowani (Gahan), while 30–50% were attacked byTetrastichus schoenobii Ferrière. About 40–90% of the eggs ofChilo were parasitised byTrichogramma? japonicum Ashmead and 5–26% byTelenomus dignus (Gahan). Only 0.4–3% of theTryporyza larvae were parasitised by a Braconid,Rhaconotus schoenobivorus (Rohwer), whileBracon chinensis Szepligeti attacked 0.2–0.7% of the larvae ofC. suppressalis. Parasitism ofSesamia larvae byApanteles flavipes Cameron was equally low, never exceeding 2%. Pupal parasitism was somewhat higher.Tetrastichus israeli (Mani & Kurian) attacked 8% and 18% of the pupae ofC. suppressalis andS. inferens, respectively, while the Ichneumonid,Xanthopimpla stemmator (Thunberg) attacked up to 3% of the pupae of the former species. The immature stages of some of these parasites are described.  相似文献   

14.
On the basis of allozyme and cultivation data, and of additional herbarium material, a taxonomic and nomenclatural revision ofTaraxacum sect.Piesis A.J. Richards exKirschner et?těpánek is provided. The section is made up of halophilous, sexually reproducing taxa. InT. stenocephalum Boiss. etKotschy,T. pindicum Kirschner et?těpánek, sp. nov., andT. perenne Kirschner et?těpánek, sp. nov., a tetraploid chromosome number has been recorded, representing the only known case of sexuality at the tetraploid level in the genus. The complex ofT. stenocephalum, includes some geographically and morphologically extreme populations treated as subspecies: subsp.gumusanicum (Soest)Kirschner et?těpánek, comb. nov., subsp.magnum Kirschner et?těpánek, subsp. nov., and subsp.daralagesicum (Schischk.)Kirschner et?těpánek, comb. nov. In addition toT. bessarabicum (Hornem.)Hand.-Mazz., a widely distributed Eurasian species,T. stenocephalum, a complex centred in Transcaucasia and Anatolia, andT. pachypodum H. Lindb., a North African endemic, four new species are described:T. salsum Kirschner et?těpánek, sp. nov., a diploid endemic confined to E Crimea,T. perenne Kirschner et?těpánek, sp. nov., a tetraploid sexual species known only from SW Crimea,T. pindicum Kirschner et?těpánek, sp. nov., a remarkable tetraploid endemic to the Pindos Mts., Greece, andT. salsitatis Kirschner, ?těpänek etYirdirimli, sp. nov., an Anatolian diploid species. Furthermore, a hybrid betweenT. salsum andT. bessarabicum from Crimea (documented on the basis of allozyme data elsewhere) is given a binomial,T. xmesohalobium Kirschner et?těpánek, nothosp. nov.  相似文献   

15.
16.
Astrocytic excitatory amino acid transporters (EAATs) regulate excitatory transmission and limit excitotoxicity. Evidence for a functional interface between EAATs and glial fibrillary acidic protein (GFAP) relevant to astrocytic morphology led to investigations of actions of transportable (d-Aspartate (d-Asp) and (2S,3S,4R)-2-(carboxycyclopropyl)glycine (l-CCG-III)) and non-transportable (dl-threo-β-benzyloxyaspartate (dl-TBOA)) inhibitors of Glu uptake in murine astrocytes. d-Asp (1 mM), l-CCG-III (0.5 mM) and dl-TBOA (0.5 mM) produced time-dependent (24–72 h) reductions in 3[H]d-Asp uptake (approximately 30–70%) with little or no gliotoxicity. All drugs induced a profound change in phenotype from cobblestone to stellate morphology and image analysis revealed increases in the intensity of GFAP immunolabelling for l-CCG-III and dl-TBOA. Cytochemistry indicated localized changes in F-actin distribution. Cell surface expression of EAAT2, but not EAAT1, was elevated at 72 h. Blockade of Glu uptake by both types of EAAT inhibitor exerts longer-term effects on astrocytic morphology and a compensatory homeostatic rise in EAAT2 abundance.  相似文献   

17.
We present the postglacial history of vegetation, human activities and changes in lake level in the context of climate change in northeast Poland from ~14,000 cal. b.p. to the present day. The palaeoecological reconstruction is based on the results of high-resolution plant macrofossil analyses as well as records from pollen, Cladocera and radiocarbon dating. Climate fluctuations and human activity have caused many changes in vegetation development in Jezioro Linówek and in the vicinity of this lake. The Early Holocene warming that occurred at ~9500 b.c. caused an increase in Betula and the colonisation of Linówek by Potamogeton lucens, Nymphaea alba and Chara sp. At ~2300 b.c., climate cooling was accompanied by the spread of Picea abies and the appearance of Potamogeton alpinus and Nuphar pumila in the lake. The first traces of farming in the form of Cerealia pollen have been dated back to ~2100 b.c. The cultivation of Triticum began at ~250 b.c., Secale at ~a.d. 550, and Fagopyrum at ~a.d. 1720. The rapid increase in human activity at ~a.d. 1700 and the simultaneous loss of woodland is associated with the establishment of villages in the area and is expressed by the decline of tree curves. In Linówek, which was formed ~14,000 cal. b.p., three periods of high water level occurred (12000–9400, 7000–4000 and 1450 b.c.a.d. 650), and two periods of low water level (9400–7100 and 3700–1700 b.c.). The changes of water level correspond well with other sites in central and northern Europe.  相似文献   

18.
Micromeles Decaisne emend.Koehne (Rosaceae, Maloideae) is shown to be generically distinct fromSorbus L. emend.Crantz. Problems in the taxonomy of the genus are reviewed. The genus appears to be most closely related toRaphiolepis Lindl. but is readily distinguished by a constant set of characters. Both genera may be derived fromSorbus L. emend.Crantz subg.Aria Pers. Analysis of morphological characters is provided. A survey for flavonoids revealed the presence of vitexin and/or luteolin 7-O-glucoside in some members of the genus in a pattern similar to that found in certain Asian species ofSorbus. There are also brief taxonomic notes on some of the species which were examined.  相似文献   

19.
Chromosome numbers are reported for 14 species collected in Cuba. The first chromosome records are reported forAlbizzia cubana Britton etWilson (2n=26),Atkinsia cubensis (Britton etWilson)Howard (2n=26),Caesalpinia violacea (Mill.)Standl. (2n=24),Colubrina ferruginosa Brongn. (2n=24). Chromosome numbers of the following species were confirmed:Albizzia lebbeck (L.)Benth. (2n=26),Canavalia maritima (Aubl.)Thouars (2n=22),Casuarina equisetifolia Forst. (2n=18),Cedrela mexicana M.J. Roem. (2n=56),Delonix regia (Bojer)Raf. (2n=28),Guazuma tomentosa H.B.K. (2n=16),Lysiloma bahamense Benth. (2n=26),L. latisiliqua (L.)Benth. (2n=26),Samanea saman (Jacq.)Merrill (2n=26),Thespesia populnea (L.)Soland (2n=26).  相似文献   

20.
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