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1.
In this study, we examined whether a satisfactory infrageneric grouping in Eremopyrum (Ledeb.) Jaub. & Spach can be achieved with the help of cluster analysis based on external vegetative and floral morphological characters of specimens either gathered from the field or borrowed from various herbaria. Twenty morphological characters were chosen and scored for 36 populations representing the genus. The data were subjected to numerical taxonomic analyses, and a phenogram was obtained by applying Gower general similarity index. The results of this study suggest that there are basically five species in Turkey, namely E. triticeum (Gaertner) Nevski, E. orientale (L.) Jaub. & Spach, E. distans (K. Koch) Nevski, E. bonaepartis (Sprengel) Nevski, and E. confusum Melderis. For the first time a new variety, E. bonaepartis (Sprengel) Nevski. var. aristatum Cabi & Do?an, is proposed along with two new combinations: E. bonaepartis (Sprengel) Nevski. var. sinaicum (Steudel) Cabi & Do?an and E. confusum Melderis var. sublanuginosum (Drob.) Cabi & Dogan. An account of Eremopyrum in Turkey is given, including a key to the species and varieties, and a general indication of their distribution.  相似文献   

2.
A revision of the genus Tecoma in Bolivia based on the author's herbarium research and extensive field observations is presented. Species delimitation is re-evaluated, resulting in the recognition of only four species, one of which, T. beckii J. R. I. Wood, is described as new. Tecoma sambucifolia is treated as var. sambucifolia (Kunth) J. R. I. Wood of the widespread and variable T. stans (L.) Juss., as it can only be distinguished on the basis of minor morphological characters and is not as geographically restricted as has been supposed. Tecoma fulva (Cav.) D. Don is treated as a variable species extending from central Peru to Chile and northern Argentina with six subspecies: ssp. fulva , ssp. guarume (A. DC.) J. R. I. Wood, ssp. tanaeciiflora (Kränzlin) J. R. I. Wood, ssp. arequipensis (Sprague) J. R. I. Wood, ssp. garrocha (Hieron.) J. R. I. Wood, and ssp. altoandina J. R. I. Wood, the latter described as new. The differences between T. tenuiflora (A. DC.) Fabris and the Peruvian T. rosifolia Kunth are discussed. Hybrids are formally recognized in the genus for the first time, and the implications for the accepted corolla morphology and pollination syndromes are discussed. Maps illustrate the geographical distributions of the species. All taxa discussed in the paper are illustrated.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 143–172.  相似文献   

3.
Z W Liu  R R Wang 《Génome》1993,36(1):102-111
To elucidate the genome constitutions of the tetraploid (2n = 4x = 28) species Elytrigia caespitosa, Lophopyrum nodosum, and Pseudoroegneria geniculata ssp. scythica and the hexaploid (2n = 6x = 42) Thinopyrum intermedium, meiotic pairing was studied in these species as well as 10 hybrids. Karyotype analysis with aceto-orcein stained root-tip cells was performed for the four species and the hybrids of T. bessarabicum with E. caespitosa, P. geniculata ssp. scythica, and T. intermedium. Karyotype analysis by Giemsa C-banding was carried out with the three tetraploid species and the two triploid hybrids involving T. bessarabicum. The species behaved as strict allopolyploids. All hybrids were male sterile with few stainable pollen grains. It is concluded from the results that the three tetraploid species have the genome formula JeJeSS and T. intermedium has the formula JeJeJeJeSS. The chromosomes of the Je and S genomes in these species had C-banding patterns differing from each other and from those of the extant diploid species. Based on these findings, the four species investigated should be placed in the same genus or the same section of a genus. However, new combinations are not proposed at this time pending future taxonomic investigation of the genome constitution of Elytrigia repens (L.) Nevski.  相似文献   

4.
For decades, the wheatgrass genus Thinopyrum has been of interest to plant breeders as a source of genes that confer competitive traits. This genus has been a considerable challenge to plant systematists because of the impacts of polyploidization on the evolution of this group. This study was aimed to augment existing cytogenetic data with a sequence-based investigation of the genomes of these species. Sequences of the internal transcribed spacer 1 (ITS1), introns 9 through 11 of the granule-bound starch synthase (GBSSI) gene and intron III of the beta-amylase gene (Bmy1) were isolated from the genomes of polyploid Thinopyrum species by PCR, cloning and sequencing and the evolutionary distances between these species and putative diploid ancestors were estimated with Kimura's two-parameter method. Phylogenetic analysis of these sequences largely agrees with what has been established through cytogenetic means for the Th. caespitosum (Koch) Liu & Wang and Ps geniculata (Trin.) á. L?ve, and suggests a contribution of the St genome of Ps. spicata (Pursh) á. L?ve to the tetraploids Th. scirpeum (Presl) Dewey and Th. junceiforme (á. L?ve & D. L?ve) á. L?ve. A unique Bmy1 allele, divergent from other Triticeae but shared between Th. caespitosum, Th. intermedium (Host) Barkworth & Dewey, Th. junceum (L.) á. L?ve and Th. ponticum Barkworth & Dewey, implies a connection between these species. Distinct oligonucleotide polymorphisms and distance calculations based on the three loci implicate Crithopsis delileana (Schult.) Roshev. and Taeniatherum caput-medusae (L.) Nevski in the evolution of the hexaploid Th. intermedium and the decaploid Th. ponticum and also suggest a potential connection of these polyploids with Elytrigia repens (L.) Desv. ex Nevski. None of these species have been previously associated with the Thinopyrum genus. Allele-specific PCR was employed to detect the putative Crithopsis allele of ITS1 in a number of accessions. Real-time PCR indicates that two of six genomes of the hexaploid Th. intermedium have the Crithopsis-type ITS1 allele and that all ITS1 loci in the decaploid Th. ponticum are of this type. These results are supportive of the hypothesis that concerted evolution has homogenized the rDNA of Th. ponticum to the allele derived from the Crithopsis or Taeniatherum ancestor. Discovery of these novel alleles, with close homology to Ta. caput-medusae, may represent a fundamental change in the view of the evolution of Th. intermedium and Th. ponticum.  相似文献   

5.
American material of Festuca brachyphylla Schult. & Schult., F. saximontana Rydb. and related species was studied. Based on morphology and anatomy F. brachyphylla was separated into three subspecies, two of which are only found in very restricted areas of the southern part of North America, one in California (ssp. breviculmis Frederiksen ssp. nov.) and one in Colorado and neighbouring states (ssp. coloraden–sis Frederiksen ssp. nov.). F. jenseni Gjaerevoll & Ryvarden was found to be the same as F. brachyphylla i.flavida Polun. and the forma level is chosen. F. brachyphylla var. groenlandica Schol. is raised to F. groenlandica (Schol.) Frederiksen. Within F. saximontana a new combination (f. saximontana Rydb. var. purpusiana Frederiksen & Pavlick) is made. American distribution of the taxa studied is mapped. A key including all the taxa has been prepared.  相似文献   

6.
The neotropical genus Triplaris Loefl. ex L. is revised. A total of 73 taxa had previously been described. In the present revision 17 species, 1 subspecies, and 1 variety are recognized. A new combination Triplaris melaenodendron (Bertol.) Standl. & Steyerm. ssp. colombiana (Meisner) Brandbyge is made, and a new variety T. setosa Rusby var. woytkowski Brandbyge is proposed. Keys based on both pistillate and staminate specimens are presented.  相似文献   

7.
B R Lu  R Bothmer 《Génome》1993,36(5):863-876
The objectives of this study were to determine the genomic constitution and to explore the genomic variation within four Chinese endemic Elymus species, i.e., E. brevipes (Keng) L?ve (2n = 4x = 28) and E. yangii B.R. Lu (2n = 4x = 28), E. anthosachnoides (Keng) L?ve (2n = 4x = 28), and E. altissimus (Keng) L?ve (2n = 4x = 28). Intraspecific crosses between different populations of the four Elymus species, as well as interspecific hybridizations among the four target species, and with six analyzer species containing well-known genomes, i.e., E. caninus (L.) L. (2n = 4x = 28, SH), E. sibiricus L. (2n = 4x = 28, SH), E. semicostatus (Lees ex Steud.) Melderis (2n = 4x = 28, SY), E. parviglumis (Keng) L?ve (2n = 4x = 28, SY), E. tsukushiensis Honda (2n = 6x = 42, SHY), and E. himalayanus (Nevski) Tzvelev (2n = 6x = 42, SHY), were achieved through the aid of embryo rescue. Chromosome pairing behaviors were studied in the parental species and their hybrids. Numerical analysis on chromosome pairing was made on the interspecific hybrids. With one exception, each meiotic configuration at metaphase I in the hybrids involving the target taxa and the analyzer species containing the "SH" genomes fit a 2:1:1 model with x-values ranging between 0.91 and 1.00; chromosome pairing in the hybrids involving analyzer parents with the "SY" genomes match a 2:2 model, with x-values between 0.97 and 0.99. All pentaploid hybrids with a genomic formula "SSYYH," except for two crosses having unexpected low c-values, had pairing patterns fitting the 2:2:1 model with x-values varying between 0.96 and 1.00. It is concluded based on hybridization, fertility, and chromosome pairing data that (i) the four target Elymus species are strictly allotetraploid taxa, (ii) they are closely related species, all comprised of the "SY" genomes, (iii) minor genomic structural rearrangements have occurred within the four Elymus species, and (iv) meiotic pairing regulator(s) exists in some of the Elymus taxa studied.  相似文献   

8.
以礼草属的分类研究   总被引:15,自引:1,他引:14  
以礼草属Kengyilia Yen et J. L. Yang 是禾本科Poaceae小麦族trib.Triticeae中新近建立的屑,针对其存在问题,对它进行了全面清理,提出了一个新的分类系统。新系统含3组、26种、6变种,其中3个组为新设立,并包括1新种、7个新等级、新组合及新异名。此外,还报道了一些类群的分布新记录。  相似文献   

9.
Kengyilia Yen et J L Yang is a recently established genus in trib. Tritieeae of Poaceae. In this paper, this genus is taxonomically revised, and a new taxonomic system is presented. The new system includes 3 sections, 26 species and 6 varieties, of which 3 sections and 1 species are described as new, 7 taxa are treated respectively in the ways of new status or combination and reduction. Three new sections, sect. Kengyilia, sect. Stenachyra L. B. Cai and sect. Hyalolepis (Nevski) L. B. Cai, are differentiated by the length and width of spike, the growing position of spikelet, the relative length of glume, the colour of anther and so on. The sect. Kengyilia contains 9 species, distributed in northwestern China, extending westward to Kazakhstan, Kirghizia, Tadzhikistan, Afghanistan and Iran; the sect. Stenachyra L. B. Cai comprises 10 species and 3 verieties, distributed in western China, mainly in the Qinghai-Xizang Plateau; and the sect. Hyalolepis (Nevski) L. B. Cai consists of about 7 species and 3 varieties, distributed in western China, extending westward to Kirghizia and Tadzhikistan. Twenty-six species of Kengyilia are recognized on the basis of the same criterion of specific concept, and the other taxa below the rank of species are also checked in terms of their external morphology. As a result, Kengyilia pen~ dula L. B. Cai is reported as a new species; K. hirsuta var. obviaristata L. B. Cai is raised to a species; K. melanthera (Keng) J. L. Yang, Yen et Baum is reduced to a variety under K. thoroldiana (Oliver) J. L. Yang, Yen et Baum; Roegneria hirsuta var. leiophylla Keng et S. L. Chen is reduced as a synonym of K. hirsuta var. hirsuta; Agropyron thoroldianum var. lasciusculum Melderis is reduced to K. grandiglumis (Keng et S. L. Chen) J. L. Yang, Yen et Baum; Roegneria rigidula var. intermedia Keng et S. L. Chen to K. rigidula (Keng et S. L. Chen) J. L. Yang, Yen et Baum; R. hirsuta var. variabilis Keng et S. L. Chen and R. rnelanthera var. tahopaica Keng et S. L. Chen to K. hirsuta (Keng et S. L. Chen)J. L. Yang, Yen et Baum. In addition, new records onthe geographical distributions of some taxa are also reported in this paper.  相似文献   

10.
Sasakawa K 《Zoological science》2005,22(11):1217-1228
Pterostichus (Nialoe) asymmetricus Bates and its allies are revised based on the membranous parts of their genitalia. Four new taxa, P. (N.) ovaliphallus sp. nov., P. (N.) fujimurai ibukiyamanus ssp. nov., P. (N.) shotaroi kiimontanus ssp. nov., and P. (N.) basilobatus sp. nov. are described. A cladistic analysis based on 31 morphological characters reveals that Daisenilaoe (s. str.) Nakane and Straneo is included as one clade within Nialoe (s. str.). The speciation and dispersal process of this species group are also discussed.  相似文献   

11.
鹅观草属部分种的叶表皮微形态特征及其分类学意义   总被引:7,自引:2,他引:5  
在过去叶表皮实验的基础上 ,本文从鹅观草属不同组、系中新增解剖了 1 6个有代表性的种。根据这些种叶片反映的表皮微形态特征 ,进一步证实了鹅观草属共族分属以及属下类群划分的正确性 ,揭示了属中各主要类群的演化水平和系统发育关系。研究结果最后表明 :鹅观草属的半颖组最原始 ,在系统发育中它可能既派生了较进化的小颖组和大颖组 ,又派生了最进化的长颖组 ;在大颖组中 ,齿草系较原始 ,纤毛草系较进化 ,宽叶草系最进化 ,纤毛草系和宽叶草系可能相继起生于齿草系。并且 ,鹅观草属的这种进化关系同过去细胞学和形态学提供的证据是基本一致的。  相似文献   

12.
The following taxa are represented in East Africa (Kenya, Tanzania, Uganda): Ornithogalum donaldsonii (Rendle) Greenway (2n=20), O. gracillimum R. E. Fries, O. tenuifolium Delaroche ssp. sordidum (Bak.) Stedje comb. nov. (2n=16), and O. tenuifolium Delaroche ssp. robustum Stedje ssp. nov. (2n = 12).  相似文献   

13.
Eight taxa are treated, viz. Hordeum pubiflorum ssp. pubiflorum (2n=14), ssp. halophilum (comb. nov.) (2n=14), H. comosum (2n=14), H. jubatum ssp. jubatum (2n = 28), H. jubatum ssp. intermedium (2n = 28), H. lechleri (2n=42), H. procerum (2n=42), and H. arizonicum (2n=42). Information about morphological variation, cytology, and genome relationship, ecology and distribution is presented.  相似文献   

14.
披碱草属(Elymus L.)两个物种之订正   总被引:3,自引:0,他引:3  
披碱草属Elymus L.是小麦族Triticeae Dumort.中最大的属,全世界共有150多个种,广泛分布于 温带地区。我国约有80余种(包括鹅观草属Roegneria C.Koch),是披碱草属的重要分布区和多样性分 化中心。由于披碱草属植物种类繁多、分布广泛、生境多样以及形态变异较为复杂,导致该属在分类上 存在许多问题。同时,由于地域的局限和地区间交流的缺乏,致使同一种披碱草属植物被不同的学者多 次发表及同物异名现象的出现。本文对E.antiquus和E.burchan-buddae这两个曾多次被订名的披碱草 属物种进行了分类订正。  相似文献   

15.
We describe a new Nosopsyllus s. sto., N. atsbi, from the north of Ethiopia, that shows phyletic similarities with N. incisus (Jordan & Rothschild, 1913), a species from the oriental part of the afrotropical region. This led us to reconsider the classification of the incisus populations based on the unique criteria of telomere's setation (three robust marginal bristles, instead of the two typically present in members of this genus and subgenus). It appears that N. incisus s. sto. occurs in north-eastern Democratic Republic of the Congo, Kenya, Burundi and Tanzania. In the north and south of this region (respectively central Ethiopia, on one hand, Zambia and Malawi, on the other hand), two taxa are morphologically distinct and we erect them here to the rank of subspecies: Nosopsyllus (N.) incisus traubi n. ssp. and N. (N.) incisus lewisi n. ssp. Actually, four taxa are in "incisus complex", namely: N. atsbi n. sp., N. incisus traubi n. ssp., N. incisus incisus (Jordan & Rothschild, 1913), and N. incisus lewisi n. ssp.  相似文献   

16.
报道了产滇东南斑果藤属的2个中国新记录,即锥序斑果藤Stixis ovata (Korth.) Hall. f. ssp. fasciculata(King) Jacobs和闭脉斑果藤S. scandens  Lour.  相似文献   

17.
Kaja Rola 《Biologia》2012,67(2):296-309
The paper presents results of morphometric analysis of Anthyllis vulneraria L. in Poland based on 828 herbarium specimens. This study investigates five taxa which have been recognized in Poland: Anthyllis vulneraria L. ssp. vulneraria, Anthyllis vulneraria ssp. polyphylla (DC.) Nyman, A. vulneraria ssp. maritima (Schweigg.) Corb., A. vulneraria ssp. alpestris Asch. et Graebn. and A. vulneraria ssp. carpatica (Pant.) Nyman as well as three intermediate taxa of presumably hybrid origin. Multivariate statistical analyses of 12 quantitative and 10 qualitative characteristics revealed conspicuous variation within A. vulneraria. Analysis of variance (ANOVA), principal coordinate analysis (PCoA), correspondence analysis (CA) and discriminant analysis (DA) proved the taxonomic usefulness of quantitative characteristics such as number of rosette leaves, calyx length, inflorescence length, the ratio of leaf length/width, bract length as well as qualitative characteristics such as stem hairiness, calyx colour, calyx indumentum, distances between stem leaves and form of rosette leaves. The issues concerning intermediate morphotypes occurring in Poland and their status are discussed. Finally, a key for determination of taxa within A. vulneraria in Poland and distribution maps based on the material examined are provided.  相似文献   

18.
Horizontal starch gel electrophoresis has been applied to thestudy of esterase, peroxidase and acid phosphatase patternsin seven taxa, namely Hordeum diploids (2n=14) (H. marinum,H. marinum I and H. hystrix), tetraploids (2n=28) (H. bulbosumand H. murinum subsp. leporinum) and Taeniatherum (2n=14) (T.caput-medusae and T. caput-medusae I) in order to elucidatetheir phylogenetic relationships. On the basis of our experimentalresults the seven taxa may be placed in the following threegroups; (1) diploid Hordeum (H. marinum, H. marinum I, H. hystrix);(2) tetraploid Hordeum (H. bulbosum, H. murinum subsp. leporinum);(3) Taeniatherum (T. caput-medusae, T. caput-medusae I). Esterase, peroxidase and acid phosphatase patterns of the twoHordeum diploid taxa (H. marinum and H. marinum I) are verysimilar suggesting their close phylogenetic relationship; thesame is true for both the taxa of the genus Taeniatherum (T.caput-medusae and T. caput-medusae I). The taxa of the Taeniatherumgroup compared with the diploid Hordeum (H. marinum, H. marinumI, H. hystrix) and the tetraploid Hordeum (H. bulbosum, H. murinumsubsp. leporinum) show a lower degree of phylogenetic relationshipand seem to be equally distant from them. The tetraploid Hordeumgroup shows a higher phylogenetic relationship with diploidHordeum group than with the Taeniatherum group. These results confirm that the genus Taeniatherum, previouslyconsidered as part of the genus Hordeum, should be regardedas a separate genus. Gramineae (Poaceae), Hordeum L., Taeniatherum Nevski., esterase, peroxidase and acid phosphatase patterns, phylogenetic relationships  相似文献   

19.
20.
Z W Liu  R R Wang 《Génome》1993,36(4):641-651
The objective of this study is to elucidate genome constitutions of Thinopyrum curvifolium (Lange) D.R. Dewey, T. scirpeum (K. Presl) D.R. Dewey, T. distichum (Thunb.) A. L?ve, and T. junceum (L.) A. L?ve. Hybrids of T. sartorii (Boiss. &Heidr.) A. L?ve with T. scirpeum and T. junceum, as well as the hybrid between T. curvifolium and Pseudoroegneria geniculata ssp. scythica (Nevski) A. L?ve, were made and chromosome pairing at metaphase I was studied. The karyotype analyses of mitotic cells stained by aceto-orcein were conducted for both hybrids and the four target species. The Giemsa C-banding following acetocarmine staining was carried out for the above species and the triploid hybrid T. curvifolium x T. bessarabicum (Savul &Rayss) A. L?ve. Meiotic data indicate that all target species have two sets of the basic genome J, but they behave like true allopolyploids because of bivalentization. Karyotypes of T. curvifolium and its triploid hybrid with T. bessarabicum indicate that T. curvifolium contains two different versions of the Jb genome, designated as Jb3 and Jb4, rather than two Je genomes as previously believed. Thinopyrum scirpeum and T. elongatum (4x) have similar karyotypes. Both are segmental allotetraploids carrying two forms of the Je genome. Their genome formulae are Je2 Je3 and Je1 Je3, respectively. Thinopyrum distichum has a karyotype similar to T. junceiforme, which has the Jb2 Je2 genome formula. However, the two species differ in C-banding patterns, reflecting their geographical separation. Thinopyrum junceum is a hexaploid with two pairs of Jb2 genomes and one pair of the Je2 genome, and it has a C-banding pattern similar to that of T. junceiforme, which has one pair each of the Jb2 and Je2 genomes.  相似文献   

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