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1.
In the course of reconstructing the Brazilian herbarium of Prince Maximilian of Wied, several species were found in the literature which need either correction or clarification. Problems include priority considerations, authority of species names, conflicting typifications and other errors. This paper reports 12 currently accepted species collected by Prince Maximilian in Brazil, commenting on their taxonomic status and nomenclature. Included are type specimens of Andromeda ambigua Schrad. (lecto and isolectotypes; = Agarista revoluta (Spreng.) Hook. f. ex Nied.), Andromeda crassifolia Nees (lecto and isolectotypes; = Agarista revoluta), Aphelandra marginata Nees & Mart. (lecto and isolectotypes), Aphelandra maximiliana (Nees) Benth. (lecto and isolectotypes), Ceiba ventricosa (Nees & Mart.) Ravenna (lectotype), Cinnamodendron axillare (Nees) Endl. ex Walp. (lecto and isolectotypes), Croton gnaphaloides Schrad. (lecto and isolectotype), C. klaenzei Müll. Arg. (holotype), Geissomeria nitida (Nees & Mart.) Nees & Mart. (lecto and isolectotypes), Nectandra squarrosa Nees var. pyrifolia Nees (lecto and isolectotypes; = Ocotea squarrosa (Nees) Mez), Ocotea squarrosa (lecto and isolectotypes), Pavonia semiserrata (Schrad.) Steud. (lecto and isolectotypes), Stenandrium serpens Nees (lecto and isolectotypes), Zollernia falcata Wied-Neuw. & Nees (lecto and isolectotypes; = Z. glabra (Spreng.) Yakovlev) and Z. splendens Wied-Neuw. & Nees (lectotype; = Z. glabra). Additionally, a new name, Aphelandra verrugensis P. L. R. Moraes, is proposed to replace Synandra amoena Schrad., which is the oldest name of the taxon currently known as Aphelandra ignea Nees.  相似文献   

2.
《Journal of bryology》2013,35(4):532-536
Abstract

The chromosome numbers of five species belonging to the Jubulae have been described, and are as follows:

Lejeuneaceae

Cololejeunea cf. dissita, n = 9.

Arehilejeunea autoiea Vanden Berghen, n=9.

Caudalejeunea hanningtonii (Mitt.) Schiffn., n =9.

Mastigolejeunea florea (Mitt.) Steph., n=9.

Frullaniaceae

Frullania spongiosa Steph., female, n = 9.

F. spongiosa Steph., male, n=8.

The author wishes to thank Dr E. W. Jones for assistance in identifications, especially with Cololejeunea cf. dissita.  相似文献   

3.
陆昭岑  邹春玉  彭华 《广西植物》2019,39(10):1412-1415
该文报道了广西禾本科(Poaceae)植物二新记录属,即菵草属( Beckmannia Host)和草沙蚕属( Tripogon Roem. et Schult.)。菵草属有2种及1变种,分布较广,我国有1种1变种,广西首次记录到该属的菵草[ Beckmannia syzigachne (Steud.) Fern.]。草沙蚕属约有30种,多分布于亚洲和非洲,我国有11种,广西首次记录到该属的线形草沙蚕( Tripogon filiformis Nees ex Steud.)。同时,还提供了2个新记录属、种的形态描述与照片。  相似文献   

4.
Abramova  L. M.  Ilyina  V. N.  Mustafina  A. N.  Karimova  O. A. 《Biology Bulletin》2019,46(10):1199-1205
Biology Bulletin - Abstract—The results of the study of 23 natural cenopopulations of Cephalaria uralensis (Murr.) Schrad. ex Roem. et Schult., a rare subendemic species of the Eastern...  相似文献   

5.
Abstract

Gagea bohemica s.l. (Liliaceae) consists of two morphologically extreme forms (saxatilis and bohemica) which depending on the varying opinions of the authors are considered as separate species, subspecies or as a single variable species. In this study, morphological (form and length of perianth segments, pilosity of pedicles and peduncles) and molecular data (cpDNA trnL–trnF IGS) of 55 samples corresponding to 43 populations from Western Europe to the Mediterranean area and eastern Caucasus were investigated. G. bohemica (Zauschn.) Schult. & Schult. f. represents a highly variable monotypic species from both morphological and karyological (2n = 24, 36, 48, 60, 72) aspects. Based on the molecular and morphological data presented here, a differentiation between specific and infraspecific taxa is not possible. We hypothesize that the morphological variability of this species is largely influenced by different site conditions and ploidy level.  相似文献   

6.
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   

7.
Abstract

Hormonal herbicides, used in pastures, can suffer drift and reach forests. The sensitivity and potential phytoremediation of native species to herbicide residues should be evaluated. The objective of this study is to evaluate the initial development of native Atlantic Forest tree species in soil contaminated with hormonal herbicides. The experiment was conducted in a greenhouse in a 4 x 8 factorial scheme. The first factor had the control and the herbicide Tordon® in three doses (0.166, 0.333 and 0.666?L ha?1) and the second consisted of the forest species Anadenanthera colubrina (Vell.), Cassia ferruginea (Schrad.) Schrad. ex DC., Dalbergia villosa (Benth.) Benth., Machaerium nyctitans (Vell.) Benth., Machaerium opacum Vogel, Piptadenia gonoacantha (Mart.) JF Macbr., Senegalia polyphylla (DC.) Britton and Rose, Senna macranthera (DC Collad.) HS Irwin and Barnaby. The emergence, height, survival, emergence speed index, intoxication, root volume, stem diameter, root and shoot dry mass, leaf area and leaf numbers of the forest species were evaluated. The A. colubrina, D. villosa and M. opacum initial development was reduced by the herbicides 2.4-D plus picloram residues. S. macranthera and P. gonoacantha are tolerant to this mixture and, therefore, show potential for phytoremediation of degraded areas containing residues of these compounds.  相似文献   

8.
Humans can unintentionally disperse plant propagules (herein referred to as seeds) including weed seeds from clothing when hiking. There is limited experimental or observational information, however, about unintended human‐mediated seed dispersal, particularly from different types of clothing. We experimentally assessed the probability of seed detaching from socks and trousers along a 5 km standardized route for eight common environmental weeds: Bidens pilosa L., Chloris gayana Kunth., Conyza canadensis L., Cynodon dactylon L., Drymaria cordata (L.) Willd. ex Schult., Poa annua L., Paspalum urvillei Steud. and Sporobolus elongatus R.Br. Seed detachment varied among species on both types of clothing, but seeds more easily detached from trousers than socks. When different models were fitted to the data, a three‐parameter generalized exponential model with curves provided the best fit. The curves were leptokurtic, with peak close to the seed source and a long flat tail, which indicates that most seeds dispersed from clothing fall close (within 5 m) to the point of attachment with only a small proportion of seeds dispersed over long distances. Combining attachment and detachment data for the same species, we estimated the actual numbers of seeds potentially dispersed over a hike of 5 km. The study indicates that most seeds are likely to be dispersed at the start of walks, although the actual number of seeds will vary depending on several factors such as the behaviour of the hiker and the amount of weed seeds present at the start of the walk. Those few seeds dispersed much further may, however, be more important in terms of plant invasions. Covering socks with gaiters and avoiding walking through weedy areas such as road edges and car parks before starting walks could minimize the risk of seeds attaching to clothing and hence being dispersed.  相似文献   

9.
10.
Abstract

Chromatic variability of tepals in species of Crocus L. of South-eastern Alps.—The anthocyanidins causing the color of tepals of some species of Crocus L. in the Italian South-eastern Alps were determined and characterized. The genus Crocus of this region is represented by four entities: C. napolitanus Mord. & Loisel., C. albiflorus Kit. ex Schult., C. reticulatus Stev. ex Adam. and C. weldenii Hoppe ex Baker.

The distribution of anthocyanidins in the four entities confirms the existence of a systematic distance among the species belonging to Reticulati and the species belonging to Anulati. Two anthocyanidins, i.e. delphynidin and petunidin, which are always present in other entities, have not been found in C. weldenii; this species is characterized by the only presence of malvidine.

The anthocyanidins assume therefore in this case a chemotaxonomic meaning.  相似文献   

11.
ABSTRACT

Cardamine battagliae Cesca & Peruzzi sp. nova is related to Cardamine heptaphylla (Vill.) O. E. Schulz. (2n = 48). On the other hand, the new species is well distinguished both from a morphological and karyological point of view. Because of its distribution and high ploidy level (2n = ca. 160) C. battagliae can be considered as a new apoendemic taxon. Morphological and karyological data are presented and discussed.  相似文献   

12.
Abstract

This study was undertaken to investigate the effects of oral L-arginine administration and exercising training on the NO concentration emanating from rat tail and NOx in plasma. Obese (fa/fa) Zucker rats (n = 22) were divided into four groups: (1) oral L-arginine administration (A) (n = 6), (2) exercise training (E), (3) exercise training + L-arginine administration (E + A) (n = 5), and (4) non-exercise training + non-L-arginine administration (N) (n = 6). The control (+/+) Zucker rats (n = 22) were also divided into the same four groups. The body weight of the E + A and the A groups was significantly lower than that of the N group. The NO concentration emitted from the tail was higher in the L-arginine (E + A and A) groups than in the non-L-arginine (E and N) groups in both obese and control rats. Exercise training did not affect the skin gas NO concentration in either obese or control rats. Plasma NOx concentrations in four obese rats were significantly higher than those observed in control rats. Exercise training did not influence the level of plasma NOx in obese or control rats. In conclusion, this study confirmed that L-arginine administration increases the skin gas NO concentration and obesity increases the plasma NOx level. The plasma NOx concentrations were not affected by L-arginine administration or exercise training in obese or control rats.  相似文献   

13.
14.
A new recorded genus, Cephalaria Schrad. ex Roem. et Schult. (Dipsacaceae), is reported here and C. gigantea (Ldb.) Bobr. is found for the first time inXinjiang, China.  相似文献   

15.
Comparative chromosomal and morphological studies indicate that four species are present in the area surveyed. Eleocharis smallii Britt. is primarily diploid with 2n = 16, although sporadic polyploids with 2n = 36 also occur. E. macrostachya Britt. is morphologically similar with unstable polyploid numbers ranging around 2n = 38 and multivalents and univalents present in meiosis. E. xyridiformis Fern. & Brack., a species generally synonymized with E. macrostachya, is shown to be a morphologically distinct species with 2n = 18, 19, and 20. The 19-chromosome types are trisomic for one of the long chromosomes, the three homologs pairing in meiosis as a large chain trivalent. The trivalent separates equationally in the first division and preferentially in the second so that only 9- or 10-chromosome pollen grains containing an extra chromosome are formed. Trisomic cytotypes may potentially produce normal (18), reconstituted trisomies (19), or tetrasomic (20) plants, although tetrasomics have not been found. The 20-chromosome cytotype is not the expected tetrasomic, as it is karyotypically distinct from either the 18 or 19 cytotypes. In all species somatic mutations including translocations, translocation-retranslocations, and chromosome fragmentation (agmatoploidy) have been observed of which the significance, if any, has not been determined.  相似文献   

16.
Meiosis and mode of reproduction are described in Agropyron ferganense Drob., a perennial forage grass from Central Asia. This species is diploid (2n = 14); it exhibits normal meiosis and reproduces by cross-pollination. Hybrids were produced between A. ferganense and six species with known genome formulas: 1) North American A. spicatum (Pursh) Scribn. & Smith, an SS diploid (2n = 14), 2) Middle Eastern A. libanoticum Hack., an SS diploid (2n = 14), 3) North American A. dasystachyum (Hook.) Scribn., an SSHH tetraploid (2n = 28), 4) Eurasian A. caninum (L.) Beauv., an SSHH tetraploid (2n = 28), 5) North American Sitation hystrix (Nutt.) J. G. Smith, an SSHH tetraploid (2n = 28), and 6) South American Elymus patagonicus Speg., an SSHHHH hexaploid (2n = 42). Almost complete chromosome pairing in the A. ferganense x A. spicatum and A. libanoticum hybrids demonstrated that A. fergenanse is an SS diploid, but it is genetically isolated from the other SS diploids because of high sterility in the F1 hybrids. S-genome diploids form a network of species that extend from the Middle East through Central Asia to western North America. Frequent occurrence of seven univalents and seven bivalents at metaphase I in the triploid hybrids of A. ferganense x A. dasystachyum, A. caninum and S. hystrix was consistent with the proposed genome formulas of SS for A. ferganense, SSHH for the three tetraploid species, and SSH for the hybrids. Chromosome pairing was highly variable in the A. ferganense x E. patagonicus hybrids; however, some cells had almost complete bivalent pairing, an expected observation in an SSHH hybrid from a cross between an SS diploid (A. ferganense) and an SSHHHH hexaploid (E. patagonicus). Various options were considered concerning the appropriate generic classification of the S-genome diploids, which are now commonly placed in Agropyron. The inclusion of these species in the genus Eiytrigia, as advocated by some Soviet taxonomists, appears to be a reasonable decision.  相似文献   

17.
Riassunto

L'A. ha studiato lo sviluppo del gametofito e dell'albume in Proboscidea Jussieui Steud. e in P. lutea Stapf: il gametofito risulta di tipo normale e Palbume di tipo cellulare fino all'inizio. Particolare attenzione è stata posta nel descrivere le caraterristiche morfologiche di due tessuti di nutrizione dell'ovulo: una modesta epistasi ed una ipostasi di proporzione notevole, fornita anche di un cambiforme. E stata pure messa in rilievo l'importanza dell'epidermide. Interna del tegumento per il mantenimento allo stato embrionale dei tessuti circostanti. Il numero dei cromosomi è 2n=30 in ambedue le specie.  相似文献   

18.
报道中国兰科植物(Orchidaceae)玉凤花属(Habenaria Willd.)一新记录种——宽叶玉凤花(H. lindleyana Steud.),并提供了该种的形态描述和野外照片。凭证标本存放于中国科学院广西植物研究所标本馆(IBK)。  相似文献   

19.
Summary Microsporogenesis, reproductive behavior, pollen fertility and seed set were studied in Pennisetum basedowii Summerhayes and C. E. Hubbard, 2n = 54; P. macrostachyum (Brough.) Trin., 2n = 54; P. macrourum Trin., 2n = 36; P. polystachion (L.) Schult, 2n = 54; and P. squamulatum Fresen 2n = 54. Meiosis was regular in P. basedowii with primarily bivalent pairing. As many as 54 univalents were observed at metaphase I in P. macrostachyum. A high frequency of univalents at metaphase I in P. macrourum resulted in lagging chromosomes and micronuclei at anaphase I and telophase I, respectively. Pennisetum polystachion and P. squamulatum showed frequent multivalent chromosome associations. Studies of megasporogenesis and embryo sac development in P. basedowii showed sexual reproduction. Pennisetum macrostachyum was highly male sterile with predominantly aposporous apomictic embryo sac development. Pennisetum macrourum, P. polystachion, and P. squamulatum had only aposporous embryo sac development. Seed propagated progenies of these latter three species were uniform and matromorphic, confirming the obligate apomixis nature.  相似文献   

20.
Hall , I. V., and L. E. Aalders . (Research Sta., Kentville, Nova Scotia.) Cytotaxonomy of lowbush blueberries in Eastern Canada. Amer. Jour. Bot. 48(3): 199–201. Illus. 1961.—The common lowbush blueberry of commercial fields in Eastern Canada, Vaccinium angustifolium Ait., is tetraploid (2n = 48). A new species, Vaccinium boreale, is similar to it but is diploid (2n = 24). The 2 species can be distinguished from each other on the basis of chromosome number, corolla length, pollen size, and degree of branching. Most vegetative characters of the 2 species overlap with varying environmental conditions, and their use for taxonomic purposes has led to confusion. V. boreale is found typically on exposed headlands in Newfoundland and has not been found in commercial fields outside that province.  相似文献   

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