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1.
Bolboschoenus maritimus (L.) Palla (=Scirpus maritimus L.) forms extensive stands in the littoral zone of small fishponds and as a weed in rice and maize fields. Within the species, two subspecies are distinguished: Bolboschoenus maritimus subsp. maritimus, B. maritimus subsp. compactus. They differ in ecology, especially in their relationships with trophic conditions and salinity of habitats. To determine growth response of these two types to different nutrient levels, we compared their seasonal development under experimental cultivation at four controlled nutrient levels. Some differences between the subspecies were found to be stable, regardless of nutrient level, namely greater amount of smaller underground tubers and more extensive rhizome system in subsp. compactus compared to less numerous larger tubers and simpler rhizome system in subsp. maritimus. In response to trophic conditions,the plants of subsp. compactus were more resistant to the conditions of the highest trophic level than those of subsp. maritimus, which were stressed. This demonstrates better adaptability and spreading ability of B. maritimus subsp. compactus at high trophic levels.  相似文献   

2.
Aims: This study was conducted to clarify the taxonomic status of Francisella sp. strain Ehime‐1, a fish pathogen, in relation to the fish pathogens F. piscicida and F. philomiragia subsp. noatunensis and to F. philomiragia subsp. philomiragia. Methods and Results: Francisella sp. Ehime‐1 was compared to F. piscicida, F. philomiragia subsp. noatunensis and several F. philomiragia subsp. philomiragia isolates through sequencing of the 16S rRNA‐gene and several house‐keeping genes and determination of biochemical and phenotypic properties. Results show that F. piscicida is indistinguishable from F. philomiragia subsp. noatunensis by sequence and phenotypic traits. Francisella sp. Ehime‐1 and F. philomiragia subsp. noatunensis are clearly separated from F. philomiragia. Francisella sp. Ehime‐1 is biochemically, phenotypically and genetically different from F. philomiragia subsp. noatunensis (=F. piscicida), but DNA–DNA hybridization does not clearly support establishment as a separate species (level of relatedness 64% and 73·4%, mean 68·7%). Conclusions: We propose to elevate F. philomiragia subsp. noatunensis to species rank as F. noatunensis comb. nov., while F. piscicida is considered a heterotypic synonym of F. noatunensis comb. nov. Evidence suggests that Francisella sp. Ehime‐1 represents a novel subspecies of F. noatunensis, for which the name F. noatunensis subsp. orientalis subsp. nov. is proposed (=DSM21254T, = LMG24544T). Significance and Impact of the Study: This study contributes to the taxonomy and characteristics of fish‐pathogenic Francisella spp.  相似文献   

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Zusammenfassung Arabis pumila Jacq. subsp.stettulata (Bebtol.)Nyman (2n=16) unterscheidet sich von subsp.pumila (2n=32) außer durch eine geringere Zahl von Stengelblättern und Blüten vor allem durch das Vorherrschen von (3-)4(-5)spaltigen Haaren im Indument insbesondere der Oberseite und des Randes der Grundblätter; bei subsp.pumila überwiegen dort 2spaltige und einfache Haare. Die beiden Unterarten wachsen in den Ostalpen etwa im gleichen Verbreitungsgebiet. Die Entstehung der subsp.pumila und die Nomenklatur beider Taxa werden diskutiert.
Chromosomal and morphological differences betweenArabis pumila Jacq. subsp.pumila (4x) and subsp.stellulata (Bertol.)Nyman (2x)
Summary Arabis pumila Jacq. subsp.stellulata (Bertol.)Nyman (2n=16) is dinstinct from subsp.pumila (2n=32) by the following characters: subsp.stellulata reveals fewer cauline leaves and flowers than subsp.pumila, in the main the former is characterized by predominating (3-)4(-5)-fid hairs especially on the upper surface and margin of the basal leaves, the latter by mainly 2-fid and unbranched hairs. In the Eastern Alps both the subspecies occur in about the same area. The origin of subsp.pumila and the nomenclature of both taxa are discussed.
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InSedum rupestre L. a polyploid series (x = 16) occurs in which aneuploid chromosome numbers and odd levels of ploidy prevail. The most common and widely distributed cytotype,S. rupestre subsp.rupestre, is 2n = 112. Plants resemblingS. rupestre subsp.rupestre can be obtained by hybridizing the tetraploid cytotypes ofS. forsterianum Sm. (2n = 48) andS. rupestre subsp.erectum 't Hart (2n = 64). Comparison of these artificial hybrids with their parents and a large number of plants ofS. rupestre subsp.rupestre (2n = 112) from nature showed thatS. rupestre subsp.rupestre and the artificial hybrids are morphologically indistinguishable, and intermediate betweenS. forsterianum andS. rupestre subsp.erectum. MorphologicallyS. rupestre subsp.rupestre is closer to subsp.erectum than toS. forsterianum. Chloroplast DNA restriction patterns ofS. rupestre subsp.rupestre, however, resembleS. forsterianum more closely. The combined results of the hybridization experiments, the analysis of the cpDNA restriction patterns, and the morphological variation indicate the allopolyploid origin ofS. rupestre subsp.rupestre. Natural hybrids inSedum (Crassulaceae) 4.  相似文献   

8.
Zusammenfassung Veronica chamaedrys L. subsp.micans M.Fischer, unterscheidet sich vonV. chamaedrys L. subsp.chamaedrys hauptsächlich durch die meist hellgrün gefärbten und im Leben oberseits stets schwach glänzenden Laubblätter, deren Blattrand durchschnittlich mehr (9–11) Zähne aufweist, durch die stets drüsenlose Infloreszenzbehaarung, die kleineren Blüten mit schmäleren Sepalen und hellblau (nicht leuchtend-sattblau) gefärbten Corollen sowie durch die diploide Chromosomenzahl (2 n=16). Sie tritt in der mittleren Bergstufe zusammen mit subsp.chamaedrys auf, ersetzt sie jedoch in der oberen Bergstufe und in der Krummholzstufe an±gleichen Standorten fast vollständig (mit Ausnahme der stark eutrophierten Standorte, die ausschließlich von subsp.chamaedrys besiedelt sind). Die neue Sippe ist bisher nur aus den nordöstlichen Alpen bekannt geworden (vgl. S. 77).
Cytotaxonomy ofveronica chamaedrys L. agg., II.: subsp.micans M.Fischer, a new diploid race
Summary Veronica chamaedrys L. subsp.micans M.Fischer differs fromV. chamaedrys L. subsp.chamaedrys mainly by: leaves bright green, in the living state always slightly but distinctly shining on the upper surface; margins on the average with more (9–11) teeth at each side; indumentum of the inflorescence without any glands; flowers relatively small with bright blue corollas and narrow sepals; chromosome number diploid: 2 n=16. In the upper mountain and subalpine region, where it replaces the common tetraploid subsp.chamaedrys L.; it is known up to now only from the Northeastern Alps (see p. 77).
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9.
Lunaria annua is overviewed and its two subspecies, subsp. annua and subsp. pachyrrhiza, discussed, the latter described. Two cultivars of subsp. pachyrrhiza, ‘Corfu Blue’ and ‘Mistras’ are illustrated and described. Details of cultivation are also included.  相似文献   

10.
Tropaeolum pentaphyllum Lam. subsp. pentaphyllum, from eastern South America is described and illustrated. The two other subspecies, subsp. megapetaloides Sparre and subsp. megapetalum (Buch.) Sparre are noted. Their habitat, pollination, distribution, and cultivation are discussed.  相似文献   

11.
Intact flagella were isolated from human pathogenic strains of Campylobacter, C. fetus subsp. intestinalis and C. fetus subsp. jejuni, by the method of DePamphilis and Adler and examined by electron microscopy. The isolated flagella were composed of a filament, a hook, a basal body, and a large disk associated with the end of the hook region covering the basal body. The width of the hook was approximately 28 nm, somewhat greater than that of the filament (20 nm in diameter). The hook region of C. fetus subsp. intestinalis was curved, but it was straight in C. fetus subsp. jejuni. The structure of the basal body of the two subspecies was similar to that reported for other gram-negative bacteria. The large disk detached from the flagella showed concentrically arranged circular structures. This structure was more clearly observed in the disk of C. fetus subsp. jejuni than in C. fetus subsp. intestinalis. Observations of thin-sectioned profiles at the attachment site of the flagellum revealed that the large disk is located on the inner side of the outer membrane. The role of the large disk in bacterial movement is not clear, but it is assumed that it acts as an organ to protect the flagellar insertion site from vigorous rotation of the polar end inflicted during bacterial movement.  相似文献   

12.
Asplenium fontanum subsp. fontanum and A. petrarchae subsp. bivalens are diploid rock ferns of limestone outcrops of the western Mediterranean region. Asplenium fontanum subsp. fontanum occurs from Valencia through northeastern Spain to the Alpes‐Maritimes and Swiss Jura. Asplenium petrarchae subsp. bivalens occurs only on Majorca, in Valencia and possibly in southern Spain. We analysed allozyme and chloroplast genetic marker diversity in 75 populations of A. fontanum subsp. fontanum and 12 populations of A. petrarchae subsp. bivalens sampled from across their respective ranges. The two species show similar levels of species and population genetic diversity to one another and to other diploid European Asplenium taxa. Both are predominantly outbreeding, as indicated by FIS = 0.108 and 0.167 respectively. Substantial between‐population differentiation results largely from differentiation between regions. Isolation by distance operates over limited geographic ranges, up to 50 km. In A. fontanum subsp. fontanum, the major geographical differentiation between Valencia and the rest of the taxon range probably represents an ancient range fragmentation. A less pronounced differentiation divides populations in the SW from those in the NE of the range, with evidence for a biogeographic link between the eastern Pyrenees and southeastern France. High diversity in the Pyrenees may either represent ancient population differentiation, or a suture zone. In A. petrarchae subsp. bivalens, populations on Majorca exhibit a subset of the genetic diversity present in Valencia, although the two regions are strongly differentiated by differing allele frequencies. Dispersal from the mainland may have founded Majorcan populations, although a role for in situ island survival cannot be excluded.  相似文献   

13.
Serpentine soils harbour a unique flora that is rich in endemics. We examined the evolution of serpentine endemism in Minuartia laricifolia, which has two ecologically distinct subspecies with disjunct distributions: subsp. laricifolia on siliceous rocks in the western Alps and eastern Pyrenees and subsp. ophiolitica on serpentine in the northern Apennines. We analysed AFLPs and chloroplast sequences from 30 populations to examine their relationships and how their current distributions and ecologies were influenced by Quaternary climatic changes. Minuartia laricifolia was divided into four groups with a BAPS cluster analysis of the AFLP data, one group consisted only of subsp. ophiolitica, while three groups were found within subsp. laricifolia: Maritime Alps, north‐western Alps and central Alps. The same groups were recovered in a neighbour‐joining tree, although subsp. ophiolitica was nested within the Maritime Alps group of subsp. laricifolia. Subspecies ophiolitica contained three different chloroplast haplotypes, which were also found in the Maritime Alps group of subsp. laricifolia. Given its high genetic diversity, subsp. ophiolitica appears to have arisen from subsp. laricifolia by vicariance instead of by long‐distance dispersal. Genetic and geographic evidence point to the Maritime Alps populations of subsp. laricifolia as the closest relatives of subsp. ophiolitica. We hypothesize that M. laricifolia was also able to grow on nonserpentine rocks in the northern Apennines during glacial periods when the vegetation was more open, but that only the serpentine‐adapted populations were able to persist until the present due to their competitive exclusion from more favourable habitats.  相似文献   

14.
The taxon commonly namedHelleborus viridis in Lombardy (NW. Italy) differs from both, subsp.viridis and subsp.occidentalis, and is shown to fall within the variation range ofH. odorus subsp.laxus which has been reported so far for NE. Italy only. TrueH. viridis within Italy grows only in the Maritime Alps.  相似文献   

15.
Dactylorhiza majalis subsp. sphagnicola is an allotetraploid marsh orchid derived from parents closely similar to present‐day D. incarnata and the western European form of D. maculata subsp. maculata, suggesting that it has a postglacial origin. It extends from northwestern continental Europe into areas formerly covered by the Weichselian ice sheet in mid‐Scandinavia. Here, we studied the variation at both the plastid and nuclear marker systems to describe the geographical variation in subsp. sphagnicola and its evolutionary history. We investigated whether subsp. sphagnicola is affected by secondary hybridization and gene flow from its parental lineages or from other allotetraploid marsh orchids, and we also compared subsp. sphagnicola with other allotetraploids of similar origins. We analysed 492 plants from 50 populations. Thirty‐seven populations were collected as potential Dactylorhiza majalis subsp. sphagnicola, five as subsp. sesquipedalis (D. elata), one as D. elata subsp. brennensis, one as subsp. calcifugiens, one as subsp. occidentalis and the remaining five as populations with some affinity to subsp. lapponica (including D. traunsteineri). All populations were analysed for plastid haplotypes and nuclear internal transcribed spacer (ITS) allele frequencies, and a subset of 43 populations was analysed for five nuclear microsatellite loci. Dactylorhiza majalis subsp. sphagnicola was dominated by a single plastid haplotype that was also dominant in western European D. maculata subsp. maculata, and most of the alternative haplotypes differed by only one mutation from the dominant one. There was more variation in nuclear microsatellites and ITS, and the variation was geographically structured in these markers. Subspecies occidentalis and calcifugiens shared haplotypes with subsp. sphagnicola, whereas subsp. sesquipedalis and brennensis had other haplotypes. Dactylorhiza majalis subsp. sphagnicola may have a postglacial origin within its present continental distribution. It has incorporated genetic material from D. maculata subsp. maculata by secondary hybridization and introgression, and some northern populations have assimilated strongly divergent haplotypes from the northeastern form of D. maculata subsp. maculata. Subspecies sphagnicola has also evolved morphologically divergent local populations in the north that do not differ from the typical populations in genetic markers. It may form mixed populations with other allotetraploid subspecies of D. majalis and, at least at one site, it has become integrated with subsp. lapponica, demonstrating that independently derived allotetraploids may contribute to a common gene pool. Subspecies calcifugiens seems to be derived from subsp. sphagnicola, and further studies based on a larger sample may confirm that it is better recognized as a variety. The so‐called D. elata subsp. brennensis is of hybrid origin and combines markers from subsp. sesquipedalis with markers from the D. majalis core complex, possibly subsp. majalis. The new combination Dactylorhiza majalis subsp. sesquipedalis (Willd.) H.A.Pedersen & Hedrén comb. nov. is provided. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 174–193.  相似文献   

16.
Abstract

A report about new or interesting plants in the Marche region. III. — The authors report about the occurrence in the Marche of 61 entities of specific or infraspecific rank, 22 of which are new or unpublished concerning the region, while the remaining 39 have been previously very little or imprecisely mentioned; as to the latter new localities and stations are shown or general information on the distribution over the Marche district has been supplied. Out of the first 22 entities, 18 (Fumaria muralis subsp. muralis, Cardamine flexuosa, Lunaria annua subsp. pachyrhiza, Colutea arborescens subsp. gallica, Astragalus monspessulanas subsp. illyricus, Cornus sanguinea subsp. australis, Galium verrucosum, Hedypnois rhagadioloides subsp. tubaeformis, Andryala tenuifolia, Sonchus asper subsp. glaucescens, Rheichardia picroides var. maritima, Podospermum canum, Scorzonera austriaca, S. hirsuta, Bidens frondosa, Guizotia abyssinica, Ambrosia elatior, A. trifida) are, as far as the authors know, quite new or unpublished concerning the Marche, while 4 (Rumex angiocarpus, Trifolium repens subsp. prostratum, Epilobium lanceolatum, Picris hieracioides subsp. spinulosa) are generally reported in Middle Italy or over the whole Italian territory by the general Floras, but till now have not been mentioned in works dealing with regional flora.  相似文献   

17.
Two subspecies of Magnolia sieboldii are described, compared and illustrated, the more frequent subsp. sieboldii and the very rare subsp. japonica. Their history and position in the genus are discussed.  相似文献   

18.
Abstract

A report about new or interesting plants in the Marche region. I. — The author points out or in some cases confirms the occurrence in this region of 107 species or subspecies. The report is based on the collections and observations made by the author himself and his collaborators during the last years. 31 of such entities (Asplenium trichomanes subsp. quadrivalens, Amaranthus blitoides, Cerastium brachypetalum subsp. roeseri, C. silvaticum, Silene alba subsp. divaricata, Ceratocephalus falcatus, Malcolmia orsiniana, Arabis collina, Fibigia clypeata, Neslia paniculata subsp. thracica, Hymenolobus pauciflorus, Biscutella didyma, Hirschfeldia incana, Rapistrum rugosum subsp. orientale, R. rugosum subsp. linnaeanum, Sempervivum italicum, Lembotropis nigricans, Chamaecytisus polytrichus, Ononis mitissima, Melilotus neapolitana, Trifolium hybridum subsp. hybridum, T. phleoides, Lotus edulis, Oxalis europaea, O. articulata, Euphorbia prostrata, Rhamnus alpinus subsp. fallax, Fumana arabica, Oenonthe lachenalii, Pimpinella tragium subsp. lithophila, Ferula communis subsp. glauca) are quite new or never dealt with for the Marche region, sometimes even for the whole central section of the Italian Peninsula; other 18 (Moehringia pentandra, Minuartia mediterranea, Stellaria nemorum subsp. glochidisperma, Cerastium semidecandrum subsp. semidecandrum, Sagina maritima, Spergularia marina, S. bocconii, Petrorhagia velutina, Adonis flammea, Sisymbrium orientale, Rorippa amphibia, Cardamine resedifolia, Capsella rubella, Potentilla detomasii, Vicia lathyroides, Trigonella monspeliaca, Hippocrepis ciliata, Geranium purpureum) are briefly reported in Middle Italy by the Italian general Floras, but till now have not been mentioned in works dealing with regional floristic. The remaining 58 entities are already known in the Marche, but scarcely reported, or their location is either not clearly defined or insufficiently described. For these new localities and stations are given, or general information on their distribution throughout the region is provided.  相似文献   

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Abstract

Critical notes on the flora of Italy. II. The Minuartia verna group. The following paper contains a re-examination of the Minuartia verna–complex in Italy based on a revision of herbarium-specimens and observations in nature. The author proposes to divide this polymorphic species into 4 subspecies. Two of them (subsp. verna and subsp. collina) are largely corresponding to the opinion of earlier authors. The subsp. attica is also represented in the flora of Southern Italy, but Italian populations are slightly different from those of Greece (which must be regarded as typical). The subsp. grandiflora living in a small area in Sicily, which was incompletely known, is described and its relations to the other subspecies are discussed.  相似文献   

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