共查询到20条相似文献,搜索用时 31 毫秒
1.
During 1988 and 1989, 409 specimens of southern African Anura, comprising 50 species in 9 families, were checked for opalinids in the cloaca. Protozelleriella devilliersi n. g., n. sp. was found in three of four Capensibufo rosei (Bufonidae); Zelleriella africana Sandon, 1938 in two of three Bufo angusticeps and one of 20 B. garmani (Bufonidae) plus three of 12 Phrynobatrachus natalensis, 12 of 19 Tomopterna cryptotis, seven of 14 T. delalandii, three of seven T. krugerensis and one of six T. natalensis (all Ranidae); Z. gambieri n. sp. in one of six T. natalensis; Z. garlandi n. sp. in two of six Kassina maculata (Hyperoliidae); Z. sandoni n. sp. in two of 20 B. garmani, two of six K. maculata, one of seven K. senegalensis and one of four Leptopelis mossambicus (Hyperoliidae) plus one of five Phrynomerus bifasciatus (Microhylidae) and two of 19 T. cryptotis. It is suggested that the Ranidae (in particular the genus Tomopterna) and the Hyperoliidae are among the major carriers of Zelleriella in the Afrotropical Region. 相似文献
2.
Abstract Several quantitative and qualitative seed characters of the seven European species of Erica sect. Loxomeria, Eremocallis and Brachycallis were studied. Two main seed types are found based on size and shape: regular ellipsoid or oblong seeds of ca. 0.4 mm for E. ciliaris and the E. tetralix group, and curved to kidney‐shaped seeds of 0.6–0.9 mm for E. cinerea, E. maderensis and E. terminalis. The testa surface in E. ciliaris is reticulate, with indented outer periclinal walls. Erica cinerea has inflated outer anticlinal walls. This character is exclusive for this species within the European (and nearby areas) species of the genus. The seeds of E. maderensis are similar to those of E. terminalis. According to seed morphology, the classical infrageneric classification, by which E. terminalis would be grouped with the E. tetralix group in sect. Eremocallis and E. maderensis in sect. Brachycallis with E. cinerea, is artificial. 相似文献
3.
A. Vilenkin 《Biopolymers》1977,16(8):1657-1675
A new technique is presented for treating the ground state of an heteropolymer with a random sequence of components. An exact system of equations is found for determining the ground state energy E which is equal to the polymer free energy f in the lowest-order approximation in T/V (V/2 is the large “surface” energy arising at the boundaries between coiled and “helical” sections: V ? T, Uk; U1 and –U2 are the free energies of the components counted from the corresponding coiled state energies). These equations are essentially simplified at certain fixed values of the ratio U1/U2. For integer values of U2/U1 and U1/U2 a solution is obtained with an accuracy exp(–V/Uk). The ground-state energy as a function of U1 and U2 is shown to be highly irregular: its derivatives have jumps at an infinite number of points. These jumps provide a fine structure of the melting curves. A smoothed over the jumps function E′ is found by way of analytic continuation from the integer values of U1/U2 and U2/U1. The accuracy of the approximation f ≈ E is estimated and the correctional term of order T/V is determined. 相似文献
4.
《Journal of bryology》2013,35(4):581-587
Abstract P. andrewsii appears to be widespread in the arctic regions of the U.S.S.R. and also in mountains of southern Siberia, the Altai Mountains. Except in the mountains of Central and Northern Europe the range of P. andrewsii does not overlap with P. annotina and P. camptotrachela. 相似文献
5.
Revision of Corallinaceae (Corallinales,Rhodophyta): recognizing Dawsoniolithon gen. nov., Parvicellularium gen. nov. and Chamberlainoideae subfam. nov. containing Chamberlainium gen. nov. and Pneophyllum
下载免费PDF全文
![点击此处可从《Journal of phycology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Annalisa Caragnano Alexandra Foetisch Gavin W. Maneveldt Laurent Millet Li‐Chia Liu Showe‐Mei Lin Graziella Rodondi Claude E. Payri 《Journal of phycology》2018,54(3):391-409
A multi‐gene (SSU, LSU, psbA, and COI) molecular phylogeny of the family Corallinaceae (excluding the subfamilies Lithophylloideae and Corallinoideae) showed a paraphyletic grouping of six monophyletic clades. Pneophyllum and Spongites were reassessed and recircumscribed using DNA sequence data integrated with morpho‐anatomical comparisons of type material and recently collected specimens. We propose Chamberlainoideae subfam. nov., including the type genus Chamberlainium gen. nov., with C. tumidum comb. nov. as the generitype, and Pneophyllum. Chamberlainium is established to include several taxa previously ascribed to Spongites, the generitype of which currently resides in Neogoniolithoideae. Additionally we propose two new genera, Dawsoniolithon gen. nov. (Metagoniolithoideae), with D. conicum comb. nov. as the generitype and Parvicellularium gen. nov. (subfamily incertae sedis), with P. leonardi sp. nov. as the generitype. Chamberlainoideae has no diagnostic morpho‐anatomical features that enable one to assign specimens to it without DNA sequence data, and it is the first subfamily to possess both Type 1 (Chamberlainium) and Type 2 (Pneophyllum) tetra/bisporangial conceptacle roof development. Two characters distinguish Chamberlainium from Spongites: tetra/biasporangial conceptacle chamber diameter (<300 μm in Chamberlainium vs. >300 μm in Spongites) and tetra/bisporangial conceptacle roof thickness (<8 cells in Chamberlainium vs. >8 cells in Spongites). Two characters also distinguish Pneophyllum from Dawsoniolithon: tetra/bisporangial conceptacle roof thickness (<8 cells in Pneophyllum vs. >8 cells in Dawsoniolithon) and thallus construction (dimerous in Pneophyllum vs. monomerous in Dawsoniolithon). 相似文献
6.
A total of 55 taxa belonging to Trachelomonas (Euglenophyta) are reported from Bangladesh. Of these, 5 varieties (Tr. allorgei var. madaripurense, Tr. anguste-ovata var. ellipsoidea, Tr. armata var. rangpurense, Tr. hispida var. subcoronata, Tr. asymmetrica var. crenulata) and one forma (Tr. anguste-ovata fa. minor) are described as new to science. 相似文献
7.
Summary The plasmid pBC16 (4.25 kbases), originally isolated from Bacillus cereus, determines tetracycline resistance and can be transformed into competent cells of B. subtilis. A miniplasmid of pBC16 (pBC16-1), 2,7 kb) which has lost an EcoRI fragment of pBC16 retains the replication functions and the tetracycline resistance. This plasmid which carries only one EcoRI site has been joined in vitro to pBS1, a cryptic plasmid previously isolated from B. subtilis and shown to carry also a single EcoRI site (Bernhard et al., 1978). The recombinant plasmid is unstable and dissociates into the plasmid pBS161 (8.2 kb) and the smaller plasmid pBS162 (2.1 kb). Plasmid pBS161 retains the tetracycline resistance. It possesses a single EcoRI site and 6 HindIII sites. The largest HindIII fragment of pBS161 carries the tetracycline resistance gene and the replication function. After circularization in vitro of this fragment a new plasmid, pBS161-1 is generated, which can be used as a HindIII and EcoRI cloning vector in Bacillus subtilis.Hybrid plasmids consisting of the E. coli plasmids pBR322, pWL7 or pAC184 and different HindIII fragments of pBS161 were constructed in vitro. Hybrids containing together with the E. coli plasmid the largest HindIII fragment of pBS161 can replicate in E. coli and B. subtilis. In E. coli only the replicon of the E. coli plasmid part is functioning whereas in B. subtilis replication of the hybrid plasmid is under the control of the Bacillus replicon. The tetracycline resistance of the B. subtilis plasmid is expressed in E. coli, but several antibiotic resistances of the E. coli plasmids (ampicillin, kanamycin and chloramphenicol) are not expressed in B. subtilis. The hybrid plasmids seem to be more unstable in B. subtilis than in E. coli. 相似文献
8.
H. M. Thomas R. A. Pickering 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,69(5-6):519-522
Summary Diploid hybrids between Hordeum chilense and three other species, namely H. vulgare, H. bulbosum and Secale cereale, are described together with the amphidiploid of H. chilensexH. vulgare. Both the diploid hybrid and the amphidiploid of H. chilensexH. vulgare were chromosomally unstable, H. chilensexH. bulbosum was less so, while H. chilensexS. cereale was stable. Differential amphiplasty was found in all combinations. No homoeologous pairing was found in the Hordeum hybrids but in H. chilensexS. cereale there was chromosome pairing both within the two genomes and between the genomes. 相似文献
9.
《Journal of bryology》2013,35(4):363-373
AbstractThree new species of Cololejeunea, C. dianae M. Wigginton, C. sanctae-helenae M. Wigginton and C. grossestyla M. Wigginton are described and illustrated from St Helena, South Atlantic Ocean. Details of their distributions are provided, and differences between the new taxa and other species of Cololejeunea are discussed. This is also the first report of the genus Cololejeunea from St Helena. 相似文献
10.
Ernest Mayer 《Plant Systematics and Evolution》1966,113(3-4):465-469
Zusammenfassung Die chorologischen und morphologisch-taxonomischen Verhältnisse vonCarlina frigida
Boiss. etHeldr.,C. fiumensis
Simk.,C. graeca
Heldr. etSart, undC. corymbosa L. im adriatischen Küstengebiet von Jugoslawien werden näher besprochen.Aus dem Gebiet des Quarnero wird der erste sichere Bastard innerhalb der GattungCarlina L.,C.×bakariensis (=C. fiumensis
Sime.×C. corymbosa L.), beschrieben. 相似文献
11.
During 1988 and 1989, 409 specimens of southern African Anura comprising 50 species in 9 families were checked for opalinids in the cloaca. Cepedea acuta n. sp. was found in six of 19 Tomopterna cryptotis and four of seven T. krugerensis (Ranidae); C. affinis (Nazaretskaja, 1992) in two of four Afrixalus aureus, two of four Hyperolius horstocki, 23 of 42 H. marmoratus, one of seven H. pusillus, two of six H. semidiscus, and eight of 12 H. tuberilinguis (Hyperoliidae); C. magna Metcalf, 1923 in one of 20 Bufo garmani, eight of 33 B. gutturalis and two of nine B. rangeri (all Bufonidae), one of two Heleophryne natalensis (juveniles) (Heleophrynidae), four of six Kassina maculata, three of seven K. senegalensis and two of six Semnodactylus wealii (all Hyperoliidae), three of five Phrynomerus bifasciatus (Microhylidae), three of 12 Phrynobatrachus natalensis, 11 of 19 Tomopterna cryptotis, 13 of 14 T. delalandii, one of seven T. krugerensis and one of six T. natalensis (all Ranidae), and four of five Chiromantis xerampelina (Rhacophoridae); Cepedea vanniekerkae n. sp. in one of 19 Tomopterna cryptotis. It is suggested that the Ranidae (in particular the genus Tomopterna) and the Hyperoliidae (in particular the genus Hyperolius) are among the major carriers of Cepedea in the Afrotropical Region. 相似文献
12.
13.
Walter Titz 《Plant Systematics and Evolution》1969,117(2):195-200
Zusammenfassung
A. sagittata (Bertol.) DC. von zehn Herkünften aus Europa ist mit 2 n=16 diploid.A. hirsuta (L.)Scop. s. str. einschließlich der sicherlich hierhergehörigen var.glaberrima
Wahlenb. von 30 europäischen Herkünften ist mit 2 n=32 tetraploid; diploide Pflanzen konnten beiA. hirsuta s. str. nicht gefunden werden.
Summary A. sagittata (Bertol.) DC. from 10 different places in Europe has 2 n=16 chromosomes and is diploid.A. hirsuta (L.)Scop. s. str., its var.glaberrima Wahlenb. being included, has been investigated from 30 provenances in Europe, it has the tetraploid chromosome number 2 n=32, diploid plants could not be found in this species.A. hirsuta var.glaberrima (2 n=32) is surely belonging toA. hirsuta s. str. and not toA. allionii (2 n=16).相似文献
14.
John G. Ormerod Linda K. Kimble Tore Nesbakken Yngve A. Torgersen Carl R. Woese Michael T. Madigan 《Archives of microbiology》1996,165(4):226-234
Two new taxa of phototrophic heliobacteria are described: Heliobacterium gestii sp. nov. and Heliophilum fasciatum gen. nov. sp. nov. Both organisms were isolated from dry paddy soils. Cells of H. gestii were motile spirilla; cells of H. fasciatum formed cell bundles that were motile as units. Both organisms produced endospores; H. gestii endospores contained dipicolinic acid and elevated levels of calcium. As with other heliobacteria, bacteriochlorophyll g was produced in both organisms and no intracytoplasmic photosynthetic membranes were observed. Growth of H. gestii and H. fasciatum occurred under both photoheterotrophic and chemotrophic conditions; nitrogen fixation also occurred in both organisms. H. gestii and H. fasciatum showed a phylogenetic relationship to the "low GC" line of gram-positive Bacteria, but H. fasciatum was distinct from H. gestii and all other heliobacteria. The ability of H. gestii and H. fasciatum to form endospores might be a significant ecological advantage for survival in their rice soil habitat.
Received: 16 October 1995 / Accepted: 10 January 1996 相似文献
15.
S. W. Hussain W. M. Williams 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(4):678-690
Trifolium ambiguum M. Bieb and T. repens L. are taxonomically related but very difficult to cross. The rare hybrids so far reported between these two species were
obtained only by embryo culture. This difficulty has been overcome in the present research by the creation of a “fertile bridge”
between T. ambiguum and T. repens. Characters of interest can now be transferred from T. ambiguum to T. repens by using this “fertile bridge” without the use of sophisticated techniques. An array of backcross progenies was generated
from crosses between a T. ambiguum×T. repens F1 hybrid (8x H-435) and its parental species. The 8x hybrid was cross-fertile only with T. repens and resulted in 145 seeds from 1578 reciprocal crosses. Eleven of nineteen initially grown BC1F1 plants were all hexaploid with an average pollen stainability of 41.6%. A high frequency of multivalents at metaphase-I indicated
that both autosyndetic and allosyndetic pairing occurred. Backcrosses of 6x BC1F1 plants to T. repens resulted in 5x BC2F1 plants with an average pollen stainability of 59.3%. On the other hand, 6x BC1F1×6x T. ambiguum crosses did not produce any seed and only two pentaploid plants were obtained from 6x BC1F1×4x T. ambiguum crosses. The difficulty encountered in generating 6x backcross progeny with 6x T. ambiguum was overcome by intercrossing the 6x BC1F1 plants and producing 6x BC1F2 plants with an average pollen stainability of 65.8%. One of these 6x BC1F2 plants was cross-compatible as a female with 6x T. ambiguum and resulted in CBC2 plants that were all cross-compatible with 6x T. ambiguum. The 6x BC1F2 plants are likely to be superior to 6x BC1F1 progeny, as they have exhibited better expression of the combined rhizomatous and stoloniferous growth habit, improved fertility,
more frequent nodal rooting and heavier nodulation. Consequently, the 6x BC1F2 plants can either be used directly in the selection programme or as a “fertile bridge” between the two parental species.
The present work has resulted in the development of a series of fertile hybrids by the manipulation of chromosome numbers,
combining the agronomic characteristics of the parent species in varying genome balances and at a range of ploidy levels.
It is concluded that the initial sterility of the primary interspecific hybrids need not be a barrier to successful inter-breeding.
Received: 2 August 1996 / Accepted: 4 April 1997 相似文献
16.
The genus Miliusa in Cambodia and Vietnam is reviewed. Cambodia and Vietnam each harbors six species of Miliusa, including three which are described as new to science: one from Cambodia (Miliusa cambodgensis sp. nov.), the other two from Vietnam (M. astiana and M. ninhbinhensis spp. nov.). In addition, a complete nomenclature and relevant information about the Miliusa species previously known from Cambodia and Vietnam are provided, including keys to the Cambodian and Vietnamese species, the designation of a lectotype for M. baillonii and the synonymization of M. balansae var. elongatoides, M. chunii and M. sinensis with M. balansae. 相似文献
17.
E. B. Peffley A. Hou 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(3-4):528-534
Allium fistulosum possesses a number of traits which would be desirable in A. cepa. Thus far, no commercial A. cepa cultivars have been released which harbor Allium fistulosum traits. F1BC3 populations were generated for this study by backcrossing A. cepa to A. cepa×A. fistulosum hybrids. The F1BC3 plants were evaluated for plant morphology, floral characters, male- sterile cytoplasm, soluble solids and pungency, and
isozymes. Overall growth habit and floral characters of the F1BC3 plants were much like A. cepa. We report here the recovery of recombinant, bulbing, and fertile A. cepa-type onions that exhibit A. fistulosum isozyme alleles and morphological markers. Recombination between A. cepa and A. fistulosum genomes was achieved using the introgression strategy of backcrossing A. fistulosum into A. cepa, thereby ameliorating the nuclear cytoplasmic barriers that occurred in previous less successful introgression attempts when
plants were not in A. cepa cytoplasm. We believe this report to be the first demonstration of onion introgressants that are like A. cepa in appearance, are male- and female-fertile, and possess A. fistulosum genes.
Received: 29 May 1999 / Accepted 22 June 1999 相似文献
18.
Robert Ornduff Theodore Mosquin Donald W. Kyhos Peter H. Raven 《American journal of botany》1967,54(2):205-213
Chromosome counts are reported for 76 taxa and 2 natural hybrids of tribe Senecioneae (Compositae). First counts are reported for several species of Senecioneae as well as for the genera Cadiscus and Whitneya. New chromosome numbers are added to those previously known in Arnica, Cacalia, and Senecio. Additional counts from Arnica support our previous suggestion that x = 19 for this genus. It is assumed that observed meiotic irregularities are associated with apomixis in this genus. Basic chromosome numbers for various New World sections of Senecio are proposed, and certain problems of sectional relationships in this genus are discussed. Chromosome numbers and plant morphology of Cadiscus, Hulsea, and Whitneya indicate that these genera should be removed from Helenieae to Senecioneae. The possible affinity of the anomalous genus Adenocaulon with Mutisieae is discussed. Data presented in the paper further support our earlier proposal that the basic chromosome number for Senecioneae is x = 10. 相似文献
19.
During 1988 and 1989, 409 specimens of southern African Anura comprising 50 species in nine families, were checked for opalines in the cloaca. Protoopalina africana Metcalf, 1923 was found in Rana angolensis (Ranidae); P. appendiculata Fantham, 1929 in R. fuscigula; P. boycotti n. sp. in Pyxicephalus adspersus (Ranidae); P. brevis Boisson, 1959 in Ptychadena oxyrhynchus (Ranidae); P. drachi Tuzet & Knoepffler, 1968 in Ptychadena anchietae, P. mascareniensis, P. mossambica and P. oxyrhynchus (Ranidae); P. nutti Metcalf, 1923 in Bufo rangeri (Bufonidae); P. octomixa Fantham, 1930 in Schismaderma carens (Bufonidae); P. ovalis Fantham, 1929 in Rana angolensis (Ranidae); P. pattersoni n. sp. in Ptychadena mascareniensis (Ranidae); P. petiti Tuzet & Knoepffler, 1968 in Ptychadena oxyrhynchus (Ranidae); P. primordialis (Awerinzew, 1913) Metcalf, 1918 in Bufo angusticeps, B. gariepensis, B. garmani, B. rangeri (Bufonidae), Heleophryne natalensis (juveniles and tadpoles) (Heleophrynidae), Xenopus laevis (juveniles and tadpoles) (Pipidae), Cacosternum boettgeri, Ptychadena mossambica (juvenile), Rana angolensis, R. fuscigula and Strongylopus grayii (Ranidae); P. stevensoni (Stevenson, 1911) Metcalf, 1923 in Bufo gariepensis, B. garmani, B. gutturalis, B. maculatus, B. rangeri, Capensibufo rosei (Bufonidae), Rana angolensis and R. fuscigula (Ranidae); P. transvaalensis Fantham, 1923 in Pyxicephalus adspersus (Ranidae); and P. xenopodos Metcalf, 1923 in Xenopus laevis (including tadpoles) and X. muelleri (Pipidae). It is suggested that the Bufonidae (genus Bufo) and the Ranidae (in particular the genera Cacosternum, Ptychadena, Rana and Strongylopus) are among the major carriers of Protoopalina in the Afrotropical Regional. The biogeography and evolution of the genus Protoopalina are discussed. 相似文献
20.
G. Caretta 《Mycopathologia》1960,12(3):233-250
Riassunto Sono studiati nelle loro caratteristiche morfo-culturali e biologiche quattro ceppi omogenei diCoremiella isolati da feci umane. Questo genera è simile aGeotrichum ma oltre a cellule miceliche clamidosporo-simili presenta formazione apicali miceliche di tipo coremioide reptante.L'artrosporulazione è un processo endogeno come inGeotrichum, e come inGeorichum si hanno artrospore clamidosporioidi fertili opache e artrospore usuali non fertili e jaline, ma meno differenziate.I ceppi vengono riferiti aC. ulmariae e le caratteristiche vengono paragonate anche con le culture su legno diSpirea ulmaria.Il primo esemplare diCoremiella è stato pubblicato comeOospora cuboidea
Sacc. etEll. come è stato accertato studiando l'esemplare autentico diEllis.In conclusione il genereCoremiella
Bub. etKrieg. è stato emendato ed è stata creata la combinazioneC. cuboidea (Sacc. etEll.).
Summary Four homogeneous strains ofCoremiella from human feces were studied from morpho-cultural and biological standpoint. This genus is likeGeotrichum, but in addition to some mycelial, chlamydospore-like cells, coremioid mycelial, reptant strands are formed.The arthrosporulation is an endogeneous process, and, likeGeotrichum, there are usual hyaline and duller chlamydosporioid, fertile arthrospores, but less differentiated.The strains are referred toC. ulmariae, and the characteristics were compared also on timber and woody European Meadowsweet cultures. But the first binomial ofCoremiella has been published asOospora cuboidea Ell. etSacc., as ascertained by the study of the authenticEllis specimen.In conclusion, the genusCoremiella Bub. etKrieg. has been emended, and the combinationC. cuboidea (Sacc. etEll.) established.相似文献