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1.
The rhizome age structure for populations ofPhragmites australis (Cav.) Trin. exSteud. was determined at three sites of the T?eboň Biosphere Reserve (Czech Republic). These sites were classified according to plant species composition and phosphorus availability as oligotrophic (Branná), mesotrophic (Ro?mberk East) and hypertrophic (Ro?mberk West).P.australis stands at these sites were expanding, stabilized and retreating, respectively. Rhizomes were sampled within the terrestrial parts of the reed stands (at a water depth of about 10 cm). The rhizomes were dated according to the position in the branching hierarchy and to supplementary morphological criteria. The analysis of the branching pattern revealed that at the sites studied, the rhizomes typically branch only once a year. The longest life span of rhizomes (six years) was found for the stable reed population at Ro?mberk East. The reduced rhizome life span at Ro?mberk West (four to five years), accompanied by a reduced branching frequency of horizontal rhizomes, was ascribed to a greater incidence of anaerobic conditions associated with the permanent flooding of the hypertrophic organic soil. The maximum life span of the Branná population (four years) probably corresponds to the total age of the reed population. The concentrations of nitrogen, phosphorus, and potassium in the tissue decreased with rhizome age while those of calcium and magnesium increased. The effect of rhizome age on mineral-nutrient concentrations was more pronounced than the effect of site on these concentrations. The mineral nutrient concentrations were not closely associated with reed performance.  相似文献   

2.
Use of morphological, karyological and enzymatic approaches in the study of 11 populations ofPhragmites australis (Cav.) Trin. exSteud. originating from different geographic areas, climates and ecological conditions reveals a spatial differentiation of populations. There is no relationship between the two levels of ploidy, 2n=48 and 2n=96, and the habitat. In contrast, the climate and environmental conditions act to the selection of the well-adapted genotypes. So, the considerable phenotypic variability ofP. australis is due to a high adaptability and an important genetic diversity.  相似文献   

3.
Plants of the common reed (Phragmites australis (Cav. Trin. exSteud.) were treated with high doses of nitrogen in an experiment performed in a sand culture and lasting one vegetation period. Nitrogen treatment resulted in alterations of growth; the increased growth of rhizomes and stalks was connected with production of significantly shorter roots. The differences in root growth were connected with changes in the internal root structure. In rhizome-borne roots, treatment with high nitrogen reduced the formation of aerenchyma and lignified layers in subapical regions. No substantial differences were observed in starch occurrence in the roots under the two treatments.  相似文献   

4.
The present study deals with African species ofSyzygiella Spruce,Allisoniella Hodgs. andGymnomitriaceae Klinggr. Three species ofSyzygiella Spruce,S. geminifolia (Mitt.) Steph.,S. concreta (Gott.) Spruce and one indeterminable species with orbicular leaves (known only in sterile condition) occur in Africa.Allisoniella nigra (Rodw.) Schust. represents a genus hitherto unreported for the African flora. The present knowledge ofGymnomitriaceae Klinggr. in subsaharan Africa is summarised; five species ofMarsupella Dum., one ofGymnomitrion Corda and five ofHerzogobryum Grolle are reported. Finally, some additions to the generaIsotachis Mitt.,Anastrophyllum (Spruce) Steph. andLophozia (Dum.) Dum. are presented.  相似文献   

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6.
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   

7.
Phytosociological analysis of savanna and forb-rich communities in the Pinar del Rio Province was done in the area of Remates de Guane; one locality lies on the seashore in the western part of the province. Altogether six associations were distinguished. Five of them, viz.Sclerio curtissii-Centelletum erectae, Schultezio guianensis-Rhynchosporetum fascicularis, Cassio diphyllae-Hypericetum stypheloidis, Polygalo squamifoliae-Dichromenetum seslerioidis andPhyllantho juncei-Aristidetum, all newly described in this paper, are classified into the order ofAcoelorapho-Colpothrinacetalia Bal.-Tul. inBal.-Tul. etCapote 1985 with two alliances. One association, thePaspalo debilis-Asteretum grisebachii Bal.-Tul. etCapote 1992, was put into the order ofAsteretalia grisebachii Bal.-Tul. inBal.-Tul. etCapote 1992 with one alliance bound to inland moving dunes. The plant composition reflects soil quality, above all the water regime. Very interesting is the presence of theByrsonimo crassifoliae-Andropogonetalia teneris-species in the association ofPolygalo-Dichromeneteum seslerioidis indicating the rich presence of stones in the upper part of the soil profile.  相似文献   

8.
The carbonaceous megafossil (mega-alga)Marpolia spissa Walcott 1919 is described from the Early Cambrian of the Barrandian area for the first time. Macroscopic remains of colonies ofM. spissa are compared with tubular microfossils of the same rocks. Different areas in colonies ofM. spissa are assignable to several (part-based) genera and species of microfossils. Therefore, the microfossil taxaSiphonophycus robustum (Schopf 1968)Knoll et al. 1991,S. typicum (Hermann 1974)Butterfield 1994,S. kestron Schopf 1968,S. capitaneum Nyberg &Schopf 1984,Polytrichoides lineatus Hermann 1974, emend.Knoll et al. 1991,Tortunema angusta (Kolosov 1984)Butterfield 1994 andTortunema wernadskii (Schepeleva 1960)Butterfield 1994 should only be used as form-species in the sense of an artificial taxonomy. The palaeoenvironment of the Paseky Shale and the biological assignment ofMarpolia spissa are discussed.  相似文献   

9.
The anamorphs in cultures ofLepista nuda (Bull.:Fr.)Cooke,Coprinus comatus (Müll.:Fr.)S.F. Gray,Fistulina hepatica Sohaeff.:Fr.,Pholiota adiposa (Fr.)Kumm. andAsterophora lycoperdoides (Bull.)S.F. Gray, an imperfect state ofNyctalis lycoperdoides (Bull.)Schroet., were studied by scanning electron microscopy. Arthroconidia were described inLepista nuda for the first time. Examination of the fine structure of dendroid forms inCoprinus comatus revealed why those structures were not propagative.  相似文献   

10.
Thirteen species and one variety ofEndophragmiella Sutton and three species ofPhragmocephala Mason etHughes collected by the author in Czechoslovakia, and occasionally in other regions of Europe are described and illustrated. Four new species and one new variety are described inEndophragmiella—E. aseptata Hol.-Jech.,E. fatrensis Holt.-Jech.,E. ramificata Hol.-Jech.,E. similis Hol.-Jech. andE. uniseptata (Ellis) Hughes var.pusilla Hol.-Jech..  相似文献   

11.
12.
On the basis of taxonomic and nomenclatural revisions of various plant groups 37 new nomenclatural combinations are proposed mostly for European phanerogamous taxa (21 for species, 14 for subspecies, 2 for hybrids.)Medicula Medicus,Pseudofumaria Medicus andThlasidia Rafin. are accepted as taxonomically justified genera and correct generic names.Dactylorhiza longebracteata (F. W. Schmidt)Holub is proposed instead ofD. fuchsii (Druce) Soó, andHylotelephium triphyllum (Haworth) Holub isstead ofH. purpureum (L.)Holub.  相似文献   

13.
Up-to-date results of taxonomic and phytogeographic studies ofOenothera subsect.Oenothera in the eastern part of the Czech Republic (Moravia and Silesia) are presented. A new hybridogenous species,Oe. moravica Jehlík etRostański (=Oe. fallax × Oe. victorini), is described from S Moravia. Several taxa and hybrids are reported for the first time for the Czech Republic:Oe. victorini Gates etCatcheside (=Oe. rostanskii Jehlík),Oe. × wienii Renner exRostański,Oe. acutifolia × Oe. victorini. Other taxa are recorded from the eastern part of the Czech Republic for the first time:Oe. acutifolia Rostański,Oe. hoelscheri Renner exRostański,Oe. parviflora L.,Oe. subterminalis Gates. The taxonomy ofOe. pycnocarpa Atkinson etBartlett is discussed. A survey of species and hybrids ofOenothera subsect.Oenothera in the Czech Republic is added.  相似文献   

14.
Three genera of lignicolousHyphomycetes Septonema Corda,Hormiactella Saac. andLylea Morgan-Jones are discussed. Illustrations and determination keys are provided. Five species ofSeptonema—S. fasciculare (Corda) Hughes,S. leptaleum (Ellis & Harkn.) Hughes,S. pinicola Hol.-Jech.,S. secedens Corda andS. laricium Hol.-Jech.—and two species ofHormiactella—H. fusca (Preuss) Sacc. andH. asetosa Hol.-Jech.—have been found in Czechoslovakia. A new speciesS. pseudobinum Hol.-Jech. is described from Romania.Septonema tetracoilum (Corda Hughes is accommodated in the genusLylea Morgan-Jones.  相似文献   

15.
16.
P. J. Joy  K. J. Joseph 《BioControl》1973,18(3):317-319
Nephantis serinopa Meyrick is now known to be parasitised by six species ofBrachymeria, viz.,B. nephantidis Gahan,B. lasus Walk.,B. excarinata Gahan,B. (Neobrachymeria) nosatoi Habu,B. euploeae Westw., andB. hime attevae Joseph Of these,B. (N.) nosatoi is the most effective pupal parasite ofN. serinopa in Kerala. Certain aspects of the biology of this parasite have been studied.  相似文献   

17.
The nameLegeriomyces Pouz. is proposed forGenistella Léger etGauthier (Trichomycetes), which is a later homonym ofGenistella Ortega (Papilionaceae). Simultaneously the family nameLegeriomycetaceae Pouz. is proposed to replace the family nameGenistellaceae Léger etGauthier.  相似文献   

18.
The present paper deals with the following three mountainOxytropis species:Oxytropis urumovii Jáv. inUrumov, an endemic species of the Pirin (Bulgaria);O. dinarica (Murb.) Wettst. distributed predominantly in Yugoslavia, andO. campestris which is common in the East Alps, but very rare in the Balkans. Three subspecies ofO. dinarica were distinguished: subsp.dinarica, subsp.weberi Chrtek etChrtková, and subsp.velebitica Chrtek etChrtková. In addition, a new combinationO. halleri Bunge exKoch subsp.korabensis (Kümmerle etJáv.)Chrtek etChrtková is given.  相似文献   

19.
Seven species ofBucania Hall 1847 from the Ordovician of Estonia are presented, also taking into consideration Pleistocene drift material from Germany, and their stratigraphical and geographical distributions are revised. The Middle Ordovician speciesBucania latissima Koken 1897 andBucania salpinx Koken 1897 are tentatively assigned toMegalomphala Ulrich inUlrich &Scofield 1897, while the Lower Ordovician speciesBucania macera Koken inKoken &Perner 1925 is placed inSalpingostoma Roemer 1876. The Middle OrdovicianBucania czekanowskii (Schmidt 1858) and the Upper OrdovicianBucania radiata (d’Eichwald 1856) were earlier considered conspecific, but based on study of the type material they are here considered distinct species.Salpingostoma cornu (Koken 1897), commonly referred to this genus because of the trema, is here transferred toBucania. Two Upper Ordovician specimens ofBucania display wide and abruptly flaring apertures morphologically far removed from other species of the genus.  相似文献   

20.
The Styginidae is regarded as an exclusively Ordovician family of trilobites, separate from the Scutelluidae. The hitherto poorly known genusProtostygina Prantl &P?ibyl, 1949 is revised. It is recorded with certainty only from the Llanvirn of the Czech Republic, and the type species is a senior synonym of“Raymondaspis” rubensi rubensi P?ibyl &VANěK, 1968 and“R.” rubensi lybar ?najdr, 1976. Two new styginid genera are proposed:Cyrtocybe, with type species“Raymondaspis” turgida Whittington, 1965, is known from the upper Arenig and lower Llanvirn of Newfoundland, Maine and Norway; andPromargo, with type speciesP.forteyi n. sp., occurs in the Arenig of Newfoundland and Spitsbergen.Turgicephalus Fortey, 1980 is regarded as a junior synonym ofRaymondaspis P?ibyl inPrantl &P?ibyl, 1949. Three genera are excluded from the Styginidae:Kirkdomina Tripp, 1962,Pseudostygina Zhou inZhou et al., 1982 andStyginella P?ibyl &Vaněk, 1971.  相似文献   

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