共查询到20条相似文献,搜索用时 15 毫秒
1.
Donald H. Burke Linda A. Raubeson Marie Alberti John E. Hearst Elizabeth T. Jordan Susan A. Kirch Angela E. C. Valinski David S. Conant Diana B. Stein 《Plant Systematics and Evolution》1993,187(1-4):89-102
We examinedchlL (frxC) gene evolution using several approaches. Sequences from the chloroplast genome of the fernPolystichum acrostichoides and from the cyanobacteriumSynechococcus sp. 7002 were determined and found to be highly conserved. A complete physical map of the fern chloroplast genome and partial maps of other vascular plant taxa show thatchlL is located primarily in the small single copy region as inMarchantia polymorpha. A survey of a wide variety of non-angiospermous vascular plant DNAs shows thatchlL is widely distributed but has been lost in the pteridophytePsilotum and (presumably independently) within the Gnetalean gymnosperms.The namefrxC was originally used to denote a gene encoding a product with probable Fe : S cluster binding activity. This activity was postulated due to the amino acid sequence similarity between this product and the Fe : S-binding nitrogenase iron proteinnifH. Fe : S-binding is a property shared by ferredoxins, which are denoted by the prefix frx. However, this gene does not encode a ferredoxin. It is much larger than any known ferredoxin, it binds its Fe : S cluster between two halves of a homodimer (Fujita & al. 1989,Burke & al. 1993 a, c) instead of within a single subunit, and it lacks the pattern of clustered cysteines present in all ferredoxins (Meyer 1988). Therefore, we use the namechlL to recognize the sequence and functional similarities to the bacterial PChlide reductase subunit,bchL. Similar usage has been adopted for this (Suzuki & Bauer 1992) and other (Choquet & al. 1992,Burke & al. 1993b) PChlide reductase subunits. 相似文献
2.
The pollination syndromes ofLeonotis (Pers.)R. Br. are discussed. Ornithophily accounts for most of the nutlets set in perennialLeonotis species but in the annual species [L. nepetifolia (L.)R. Br.] autogamy prevails.Leonotis species are predominantly pollinated by a variety of sunbirds, although bees are also involved. Nectar is sucrose-dominant in perennial species but hexose-dominant in the annual. 相似文献
3.
The esterase and peroxidase patterns in five varieties ofAegilops caudata (genome type C) andAe. comosa (genome type M) were studied in order to elucidate the phylogenetic relationships within and between the two groups. The electrostarch gel electrophoresis technique was applied to extracts of shoot and root of 4-day-old seedlings, and the electropherograms were evaluated by gel densitometer traces. Inspite of considerable isozyme polymorphism, closer relationships in the banding patterns were found between different varieties of a single species than between varieties of the two different species. Esterase and peroxidase patterns of the twoAe. caudata varieties (caudata andpolyathera) are very similar and prove their close phylogenetic relationship. The isozyme affinities withinAe. comosa varieties are illustrated by the seriessubventricosa—biaristata—thessalica. The latter endemic variety has quite a number of characteristic bands and is relatively isolated. Altogether, the electrophoretic data agree well with morphological and cytological similarities (Zhukovsky 1928,Eig 1929,Karataglis 1973, 1975b). 相似文献
4.
Kagkli DM Tâche R Cogan TM Hill C Casaregola S Bonnarme P 《Applied microbiology and biotechnology》2006,73(2):434-442
Cheese flavour is the result of complex biochemical transformations attributed to bacteria and yeasts grown on the curd of smear-ripened cheeses. Volatile sulphur compounds (VSCs) are responsible for the characteristic aromatic notes of several cheeses. In the present study, we have assessed the ability of Kluyveromyces lactis, Kluyveromyces marxianus and Saccharomyces cerevisiae strains, which are frequently isolated from smear-ripened cheeses, to grow and deacidify a cheese medium and generate VSCs resulting from l-methionine degradation. The Kluyveromyces strains produced a wider variety and higher amounts of VSCs than the S. cerevisiae ones. We have shown that the pathway is likely to be proceeding differently in these two yeast genera. The VSCs are mainly generated through the degradation of 4-methylthio-oxobutyric acid in the Kluyveromyces strains, in contrast to the S. cerevisiae ones which have higher l-methionine demethiolating activity, resulting in a direct conversion of l-methionine to methanethiol. The deacidification activity which is of major importance in the early stages of cheese-ripening was also compared in S. cerevisiae and Kluyveromyces strains. 相似文献
5.
David L. Hawksworth 《Plant Systematics and Evolution》1985,149(3-4):303-307
The nomenclatural history of the generic nameParmeliopsis is reviewed. Its correct citation is found to beParmeliopsis (Nyl. exStizenb.)Nyl., dating from 1866, not 1869 as commonly cited, withP. placorodia (Ach.)Nyl. as holotype species. There is consequently no nomenclatural problem to the adoption ofForaminella
Fricke Meyer, typified byF. ambigua (Wulfen)Fricke Meyer for theParmeliopsis species with falcate conidia. A synopsis of the nomenclature of the North American and European species of both these genera is included. 相似文献
6.
Eberhard Baumann 《Plant Systematics and Evolution》1978,130(1-2):43-52
A report is given on about 1000 specimens of 28 species ofPhorinae and their occurrence on 12 species ofUmbelliferae. Collections were made in a variety of habitats ranging from the German North Sea coast up to altitudes of 2500 m in the Western Alps. The morphology of the mouth-parts of the flies and their behaviour on the umbels are discussed briefly. No specific adaptations exist between Phorid flies and the visited umbels; their relationship is mutualistic. Climate and altitude have a greater influence on frequency and diversity of these visitors than the host-plants themselves. Visitors frequency and diversity increases with altitude.
Rennfliegen (Phoridae/Diptera) als Blütenbesucher, II. — Vgl. dazuBaumann (1978a). 相似文献
7.
Olof Ryding 《Plant Systematics and Evolution》1993,185(1-2):91-97
The two generaPlectranthus andIsodon are compared and found to be very dissimilar.Isodon ist considered to be misplaced inOcimeae subtribePlectranthinae and apparently is more closely related to subtribeHyptidinae. The disjunct genusRabdosiella is compared to these two genera and regarded to be polyphyletic. The AfricanR. calycina (Benth.)Codd is returned toPlectranthus and calledP. calycinus
Benth., while the AsianR. ternifolia (D. Don)Codd is placed inIsodon sect.Pyramidium and calledI. ternifolius (D. Don)Kudo. 相似文献
8.
J. Francisco-Ortega J. G. Hawkes R. N. Lester J. R. Acebes-Ginovés 《Plant Systematics and Evolution》1993,185(3-4):189-205
Morphological data and results from scanning electron microscopy of seeds and pollen show thatNormania
Lowe [syn.Solanum L. subg.Potatoe (G. Don)D'Arcy sect.Normania (Lowe)Bitter] (Solanaceae: Solaneae) should be considered as a distinct genus fromSolanum L. It has two species, one restricted to the island of Madeira [Normania triphylla (Lowe)Lowe] and the other to Tenerife and Gran Canaria [Normania nava (Webb & Berthel.)Franc.-Ort. & R. N. Lester]. These species are extremely rare and had not been found for about 100 years, untilN. nava was rediscovered in two different localities in Tenerife in 1973 and 1982.Normania triphylla was reported in two different places from northern Madeira in 1991. Both species have the highest conservation priority in the Macaronesian region. 相似文献
9.
Mats Wedin 《Plant Systematics and Evolution》1993,187(1-4):213-241
A phylogenetic analysis of the familySphaerophoraceae (Caliciales, lichenized ascomycetes) has resulted in a new generic classification. Notes on character evolution are given. The generaSphaerophorus s. str.,Bunodophoron andLeifidium, gen. nov., are accepted.Pleurocybe andPseudosphaerophorus are considered synonyms ofBunodophoron andThysanophoron is considered synonym toSphaerophorus. The following new combinations are proposed:Bunodophoron coomerense (Ohlsson)Wedin,B. diplotypum (Vain.)Wedin,B. dodgei (Ohlsson)Wedin,B. flaccidum (Kantvilas & Wedin)Wedin,B. formosanum (Zahlbr.)Wedin,B. imshaugii (Ohlsson)Wedin,B. insigne (Laurer)Wedin,B. kinabaluense (M. Satô)Wedin,B. macrocarpum (Ohlsson)Wedin,B. madagascareum (Nyl.)Wedin,B. microsporum (Ohlsson)Wedin,B. murrayi (Ohlsson)Wedin,B. notatum (Tibell)Wedin,B. ohlssonii (Wedin)Wedin,B. patagonicum (C. W. Dodge)Wedin,B. ramuliferum (I. M. Lamb)Wedin,B. scrobiculatum (C. Bab.)Wedin,B. tibellii (Wedin)Wedin,B. whakapapaense (Wedin)Wedin, andLeifidium tenerum (Laurer)Wedin. 相似文献
10.
Per Hartvig 《Plant Systematics and Evolution》1987,155(1-4):197-213
TheThymus teucrioides
Boiss. & Spruner aggregate is revised and the following new taxa, all from the alpine zone in the Greek mountains, are described:Th. leucospermus
Hartvig from the calcareous mountains of Pindhos and Mt Parnassos in Sterea Ellas,Th. rechingeri
Hartvig with the subsp.macrocalyx
Hartvig from calcareous mountains in Sterea Ellas and N Peloponnissos, andTh. teucrioides subsp.alpinus
Hartvig from the serpentine areas of N Pindhos. In the variableTh. teucrioides s. str. many characters have turned out to be markedly geographically correlated and many local populations can be distinguished by a particular combination of characters.Dedicated to Prof.K. H. Rechinger on the occasion of his 80th birthday. 相似文献
11.
Harald Riedl 《Plant Systematics and Evolution》1981,138(3-4):283-286
Cynoglossopsis somaliensis
H. Riedl, sp. nov., is described as a new species of the hitherto monotypic genusCynoglossopsis
Brand which is closest related toCynoglossum L. but has to be included inBoraginoideae-Eritrichieae from the way the nutlets are attached to the gynobasis. 相似文献
12.
C. den Hartog J. Hennen Th. M. P. A. Noten R. J. van Wijk 《Plant Systematics and Evolution》1987,156(1-2):55-59
The chromosome numbers of the five European seagrasses have been determined in material from several sites along the coasts of the Atlantic Ocean, the North Sea and the Mediterranean:Zostera marina L., 2n = 12;Z. noltii
Hornem., 2n = 12;Posidonia oceanica (L.)Delile, 2n = 20;Cymodocea nodosa (Ucria)Aschers., 2n = 14, 2n = 28;Halophila stipulacea (Forsk.)Aschers., 2n = 18. The difference in chromosome morphology betweenZ. marina andZ. noltii supports the division of the genus into two subgenera. 相似文献
13.
Epiphytes of Paralemanea catenata (Kützing) Vis & Sheath (Rhodophyta) were studied on material from the River Dyje in National Park Podyjí. Longitudinal sections of the thalli were
made with help of Cryo Cut Microtome techniques. The epiphytic cyanophytes Xenococcus kerneri
Hansgirg and Chamaesiphon minutus (Rostafinski) Lemmermann were recognized on the cortex of the thalli. Our observations of the determined species are discussed. 相似文献
14.
Four very rare species ofAgaricales of dry grassland of the Galgenberg near Röschitz (Niederösterreich) are described and their taxonomy, affinities, ecology and distribution are discussed.Marasmiellus graminis (Murr.)Sing. & Hausknecht andCrinipellis subtomentosa (Peck.)Sing. var.mauretanica (Mre.)Sing. & Hausknecht are proposed as new combinations;Campanella inquilina
Romagn. apudRedhead is a synonym ofC. caesia
Romagn. 相似文献
15.
T. R. Deason P. C. Silva S. Watanabe G. L. Floyd 《Plant Systematics and Evolution》1991,177(3-4):213-219
Komárek has recently reviewed the various species assigned to the green algal genusNeochloris
Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia.
Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class. 相似文献
16.
Interspecific hybridizations were made between species of theE. semicostatus group, viz.,E. semicostatus (Nees exSteud.)Meld.,E. validus (Meld.)B. Salomon,E. abolinii (Drob.)Tzvel., andE. fedtschenkoi
Tzvel., and species of theE. tibeticus group, viz.,E. pendulinus (Nevski)Tzvel.,E. tibeticus (Meld.)Singh,E. shandongensis
B. Salomon, andE. gmelinii (Ledeb.)Tzvel., as well as among species within theE. tibeticus group. All species are tetraploid (2n = 4x = 28) and possess SY genomes. Meiotic pairing data from 24 hybrids involving 17 interspecific combinations are presented. The average number of chiasmata per cell ranged from 17.91 to 26.20 in hybrids within theE. tibeticus group, compared with 7.26 to 22.04 in hybrids between the two species groups. Despite the extensive collection of cytological data, there was no definite evidence for confirming or disproving the separate existence of the two groups. 相似文献
17.
Focko Weberling Hermann Lörcher Evelyn Böhnke 《Plant Systematics and Evolution》1980,133(3-4):261-283
TheSimaroubaceae generally have no true stipules. The stipule-like appendages of some genera proved to be pseudo- or metastipules (Weberling & Leenhouts 1965). There seem to be some exceptions, however: the generaCadellia (incl.Guilfoylia) andRecchia on the one hand, and theIrvingioideae on the other. As these taxa, with exception ofRecchia, have simple leaves, there are no indications that their stipule-like appendages might be pseudo- or metastipules. In regard to their position and ontogeny these appendages behave completely like true stipules. Assuming the view ofForman, one could conceive a morphological line from the long, broadly inserted axillary stipules of mostIrvingioideae to the small scaly triangular stipules ofIxonanthoideae. The similarities between the stipules ofIrvingioideae andErythroxylaceae (already emphasized byHallier and others), become even more evident when their ontogeny is investigated. TheIrvingioideae, therefore, might be regarded as a separate family (perhaps with some relation to theErythroxylaceae,Hallier) or as a subfamily ofIxonanthaceae (Forman).—In addition to data on stipules some results on the palynology and shoot anatomy of the generaCadellia (incl.Guilfoylia) andRecchia are reported. Their relationship with theSimaroubaceae also appears doubtful. If they are to be included, they represent a somewhat isolated group near the base of the family which otherwise has lost its stipules.
Herrn Univ.-Prof. Dr.Walter Leinfellner zum 70. Geburtstag gewidmet. 相似文献
18.
T. marconae is described as a new species from the Peruvian coastal desert. Its systematic position betweenT. paleacea
Presl em.L. B. Smith andT. purpurea
Ruiz & Pavon is discussed. 相似文献
19.
Bernard Priem Julien Solokwan Jean-Michel Wieruszeski Gérard Strecker Hassan Nazih Henri Morvan 《Glycoconjugate journal》1990,7(2):121-132
The oligosaccharides Man5GlcNAc and Man3(Xyl)GlcNAc(Fuc)GlcNAc presumed to originate fromN-glycosyl proteins have been purified from an extracellular medium (concentration: 2–5 mg/l of 14 day cultures) of white campion (Silene alba) suspension culture. Their primary structures have been determined by1H-400-MHz NMR spectroscopy and FAB-MS spectrometry. They are probably the result of an autophagic process including protein catabolism due to sucrose starvation. Additional identification of digalactosylglycerol (galactolipid breakdown) argues for this hypothesis.Abbreviations Fuc
l-fucose
- Man
d-mannose
- Xyl
d-xylose
- GlcNAc
N-acetyl-d-glucosamine
- Gal
d-galactose
- Glc
d-glucose
- FAB-MS
fast atom bombardment mass spectrometry
- NMR
nuclear magnetic resonance 相似文献
20.
The hypothesis ofHenriques andFernandes that several Iberian species ofNarcissus (Amaryllidaceae) are tristylous is reconsidered. Contrary to the opinion ofBateman and most subsequent authors, we believe that the available evidence indicates that some populations ofN. triandrus andN. fernandesii, at least, are tristylous; other populations ofN. triandrus are distylous.Hugonia cf.penicillanthemum (Linaceae) from new Caledonia is distylous, but it remains possible that other species ofHugonia are tristylous. The disputed occurrence of heterostyly in S. African species ofBauhinia (Leguminosae),Cleome (Capparaceae) andAneilema (Commelinaceae), and inAgelaea (Connaraceae) is discussed. 相似文献