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1.
A taxonomic revision of Psathyrostachys (Poaceae) 总被引:1,自引:0,他引:1
Claus Baden 《Nordic Journal of Botany》1991,11(1):3-26
2.
This paper presents the chromosome numbers of nine species from the section AlchemUla , subsection Heliodrosium , series Vulgares. The studies were carried out on plants from the Northeast Anatolia (Turkey). The following chromosome numbers have been detected; A. valdehirsuta 2n= 96–106, A. monticola 2n= 101–110, A. stevenii 2n= 98–106, A. crinita 2n= 102–108, A. compactilis 2n= 98, A. heterophylla 2n= 100–105, A. minusculiflora 2n= 87–97, A. pseudocartalinica 2n= 98–108, A. straminea 2n= 80–91. The species of genus AlchemUla studied from Northeast Anatolia are proven to be polyploids like the majority of species from the section AlchemUla investigated from various geographic areas. 相似文献
3.
The localization of Mn(2+) in A-tract DNA has been studied by (1)H NMR spectroscopy using a series of self-complementary dodecamer oligonucleotides that contain the sequence motifs A(n)(n) and T(n)A(n), where n = 2, 3, or 4. Mn(2+) localization in the minor groove is observed for all the sequences that have been studied, with the position and degree of localization being highly sequence-dependent. The site most favored for Mn(2+) localization in the minor groove is near the 5'-most ApA step for both the T(n)A(n) and the A(n)T(n) series. For the T(n)A(n) series, this results in two closely spaced symmetry-related Mn(2+) localization sites near the center of each duplex, while for the A(n)T(n) series, the two symmetry-related sites are separated by as much as one half-helical turn. The degree of Mn(2+) localization in the minor groove of the T(n)A(n) series decreases substantially as the AT sequence element is shortened from T(4)A(4) to T(2)A(2). The A(n)T(n) series also exhibits length-dependent Mn(2+) localization; however, the degree of minor groove occupancy by Mn(2+) is significantly less than that observed for the T(n)A(n) series. For both A(n)T(n) and T(n)A(n) sequences, the 3'-most AH2 resonance is the least broadened of the AH2 resonances. This is consistent with the observation that the minor groove of A-tract DNA narrows in the 5' to 3' direction, apparently becoming too narrow after two base pairs for the entry of a fully hydrated divalent cation. The results that are reported illustrate the delicate interplay that exists between DNA nucleotide sequence, minor groove width, and divalent cation localization. The proposed role of cation localization in helical axis bending by A-tracts is also discussed. 相似文献
4.
In this work we analyzed the karyotype of five populations of Adenomera diptyx from Argentina after conventional staining, Ag-NOR and C-banding. All specimens presented 2n = 26 and FN = 34. The karyotype was formed by three submetacentric, one metacentric and nine telocentric pairs. Silver staining revealed that the NOR was located on a secondary constriction in pair 7. C- banding evidenced constitutive heterochromatin at the pericentromeric region of all chromosomes. The karyotype of A. diptyx was similar to that of A. hylaedactyla (2n = 26, FN = 34) and different from that of A. andreae (2n = 26, FN = 40) in the fundamental number and secondary constriction position. It also differed from the karyotypes of A. marmorata (2n = 24, FN = 34 and 36) and of A. aff. bokermanni (2n = 23, FN = 34) in diploid number. Until a comprehensive cytogenetic analysis of all the species of the genus is performed, their chromosome evolution will remain poorly understood. 相似文献
5.
The strawberry genus, Fragaria (Rosaceae), has a base chromosome number of x = 7. Cultivated strawberries (F. ×ananassa nothosubsp. ananassa) are octoploid (2n = 8x = 56) and first hybridized from F. chiloensis subsp. chiloensis forma chiloensis × F. virginiana subsp. virginiana. Europe has no known native octoploid species, and only one Asian octoploid species has been reported: F. iturupensis, from Iturup Island. Our objective was to examine the chromosomes of F. iturupensis. Ploidy levels of wild strawberry species, include diploid (2n = 2x = 14), tetraploid (2n = 4x = 28), pentaploid (2n = 5x = 35), hexaploid (2n = 6x = 42), octoploid (2n = 8x = 56), and nonaploid (2n = 9x = 63). Artificial triploid (2n = 3x = 21), tetraploid, pentaploid, octoploid, decaploid (2n = 10x = 70), 16-ploid, and 32-ploid plants have been constructed and cultivated. Surprisingly, chromosome counts and flow cytometry revealed that F. iturupensis includes natural decaploid genotypes with 2n = 10x = 70 chromosomes. This report is the first of a naturally occurring decaploid strawberry species. Further research on F. iturupensis and exploration on northern Pacific islands is warranted to ascertain the phylogeny and development of American octoploid species. 相似文献
6.
Morphometric karyotype characters were studied in 25Angelica spp. (Umbelliferae, Apioideae) and in one species of the related genusTommasinia. For three species the chromosome numbers are new. In our study the majority of the species investigated are diploids with 2n = 22, some are tetraploids with 2n = 44 (for these tetraploids also diploid cytotypes are reported in the literature). Among the diploid species,A. miqueliana has a distinct karyotype consisting of submetacentric and acrocentric chromosomes only, the remaining diploids with 2n = 22 as well as tetraploids with 2n = 44 have rather symmetrical karyotypes, consisting of metacentric and submetacentric chromosomes. The very different chromosome number 2n = 28 has been found inA. gmelinii. Its karyotype includes two distinct groups of chromosomes: 8 pairs of rather large metacentrics and submetacentrics and 6 pairs of very short and asymmetrical chromosomes. Chromosome numbers and structures appear to be useful in the taxonomy of some intrageneric taxa inAngelica. 相似文献
7.
Investigation of chromosome numbers of allAzolla species, and for the first time of hybrids, has been undertaken. Removal of wax from the leaf surface proved invaluable in achieving clear cytological preparations and providing unambiguous chromosome numbers. In contrast to previous records, the speciesA. pinnata, A. filiculoides, A. filiculoides var.rubra, A. caroliniana, A. microphylla, andA. mexicana were found to be 2n=44, andA. nilotica to be 2n=52. Several triploids (2n=66) and one tetraploid (2n=88) were identified. No geographical pattern could be observed in the distribution of triploids which probably derive from the function of unreduced gametes. The chromosome number of hybrids occasionally deviates from the diploid chromosome number (2n=44). The small chromosome size limits karyotypic analysis and only differences in overall chromosome size can be observed. Taxonomic implications of chromosome numbers and sizes are discussed. 相似文献
8.
Sung-Kong Yip Chui-Ling Chan Wai Han Lam Kung-Kai Cheung Vivian Wing-Wah Yam 《Photochemical & photobiological sciences》2007,6(4):365-371
A series of pentanuclear gold(I)-copper(I) and -silver(I) mixed-metal alkynyl complexes, [(n)Bu(4)N][Au(3)M(2)(C triple bond CC(6)H(4)R-p)(6)] [M = Cu, R = OMe, O(n)Bu, O(n)Hex, Me, Et; M = Ag, R = Et, O(n)Hex] have been synthesized. The complexes were found to be emissive both in the solid state and in fluid solutions. DFT calculations at the B3LYP level of theory were performed on [Au(3)M(2)(C triple bond CC(6)H(4)Me-p)(6)](-) (M = Cu, Ag) to provide an understanding on the electronic structure of the complexes. 相似文献
9.
YANG Qin-Er 《植物分类学报:英文版》2002,40(5):396-405
The somatic chromosome number and detailed chromosome morphology have been studied in ten species of Anemone, one species of Anemoclema, and six species of Clematis, all from China, namely Anemone davidii Franch. (2n=4x= 32), A. stolonifera Maxim. (2n=2x=16), A. flaccida Fr. Schmidt (2n=2x= 14), A. rivularis Buch.-Ham. (2n=2x= 16), A. begoniifiolia lévl. et Vant. (2n=2x= 16), A. hupehensis Lem. f. alba W. T. Wang (2n =2x = 16), A. tomentosa (Maxim.) Péi (2n=2x= 16), A. rupestris Hook. f. et Thoms. (2n=2x= 14), A. trullifolia var. colestina (Franch.) Finet et Gagnep. (2n = 2x = 14), A. trullifolia var. holophylla Diels (2n=2x= 14), A. demissa Hook. f. et Thoms. (2n=2x= 14), Anemoclema glaucifolium (Franch.) W. T. Wang (2n= 2x= 16), Clematis kockiana Schneid. (2n= 2x=16), C. rehderiana Craib. (2n = 2x = 16), C. ranunculoides Franch. (2n = 2x = 16), C. puberula var. ganpiniana(Lévl. et Vant. ) W. T. Wang (2n = 2x = 16), C. brevicaudata DC. (2n= 2x= 16), C. chrysocoma Franch. (2n = 2x = 16). The species of x = 8 in Anemone, and those in Anemoclema and Clematis have very similar karyotypes which consist of five pairs of large median-centromeric (rarely one pair of which are submedian-centromeric) and three pairs of subterminalor terminal-centromeric chromosomes. 相似文献
10.
国产毛茛科银莲花族十七种植物的细胞学研究 总被引:2,自引:0,他引:2
研究了国产毛茛科银莲花族Trib.Anemoneae 17种植物的染色体数目和核型。10种银莲花属
Anemone L.植物中,1种(西南银莲花A.davidii)为x=8的四倍体(2n=4x=32),5种(匍枝银莲花A.
stolonifera、草玉梅 A.rivularis、卵叶银莲花A .begoniifolia、水棉花A.hupehensis f. alba、大火草A.tomen-
tosa)为x=8的二倍体(2n=2x=16),4种(鹅掌草A.flaccida、湿地银莲花A.rupestris、蓝匙叶银莲花
A.trullifolia var.colestina、拟条叶银莲花A.trullifolia var.holophylla、展毛银莲花A.demissa)为x=7的
二倍体(2n=2x=14)。罂粟莲花Anemoclema glaucifolium 为x=8的二倍体。6种铁线莲属Clematis L.植
物(滇川铁线莲C.kockiana、长花铁线莲C.rehderiana、毛茛铁线莲C.ranunculoides、扬子铁线莲C.
puberula var.ganpiniana、短尾铁线莲C.brevicaudata、金毛铁线莲A.chrysocoma)均为x=8的二倍体。银
莲花属中x=7的种类的核型彼此十分相似,均由6对大型具中部着丝点的染色体和1对具端部着丝点
的染色体组成;x=8的二倍体种类的核型与罂粟莲花属和铁线莲属植物的核型十分相似,均由5对大型 具中部着丝点和3对具端部或近端部着丝点的染色体组成。 相似文献
11.
国产十五种翠雀族植物的核型研究 总被引:10,自引:2,他引:8
本文报道了国产乌头属Aconitum L.12种和翠雀属Delphinium L.3种植物的染色体数目和核型。花葶乌头A.scaposum var.scaposum和聚叶花葶乌头A.scaposum var.vaginatum的核型公式为2n=2m+6sm+8st;两色乌头A.alboviolaceum为2n=16=2m+6sm(2sat)十8st;高乌头A.sinomontanum var.sinomontanum为2n=16=4m+4sm+8st,而狭盔高乌头A.sinomontanum var.angustius为2n=32=6m+6sm+20st(1sat);褐紫乌头A.brunneum为2n=16=2m(1sat)+14sm 松潘乌头A.sungpanense为2n=16=6m(2sat)+10sm(2sat);弯枝乌头A.arcuatum为2n=16=4m+12sm;乌头A.carmichaeli为2n=32=10m+22sm;北乌头A.kusnezoffii为2n=32=10m十22sm;鸭绿乌头A.jaluense为2n=32=10m+22st;伏毛铁棒锤A.flavum为2n=16=2m+14sm; 铁棒锤A.pendulum为2n=16=4m+12sm;缩梗乌头A.sessiliflorum为2n=16=2m+10sm+4st;展毛翠雀花D.kamaoense var.glabrescens 为2n=16=2m+6sm+8st;蓝翠雀花D.caeruleum为2n=16=2m+6sm+8st;多枝翠雀花D.maximowiczii为2n=16=2m+6sm+8st。其中花葶乌头、狭盔高乌头、褐紫乌头、松潘乌头、鸭绿乌头、伏毛铁棒锤、缩梗乌头、展毛翠雀花、蓝翠雀花、多枝翠雀花的染色体数目和核型为首次报道。 相似文献
12.
中国含笑属核型分析 总被引:8,自引:0,他引:8
对我国木兰科Magnoliaceae含笑属Michelia 12个种的核型进行了研究,核型公式如下:火力楠
M.macclurei var.sublanea 2n=34m(2SAT)+4sm;白兰M.alba 2n=34m+4sm;多花含笑M.flori-
bunda 2n=30m+8sm;黄兰M.champaca 2n=32m+6sm;石碌含笑M.shiluensis 2n=32m+6sm;阔
瓣含笑M . platypetala 2n=32m+6sm(2SAT);含笑M.figo 2n=32m+6sm;深山含笑M.maudiae
2n=32m+6sm;长蕊含笑M. longistamina 2n=32m=6sm;金叶含笑M.foveolata 2n=34m=4sm;
野含笑M.skineriana 2n=30m+8sm;峨嵋含笑M.wilsonii 2n=30m+8sm(2SAT)。该属核型全部为
对称核型,除多花含笑为1A类型外,其他均为2A核型。含笑属种间核型具有很大相似性,核型资料对该属属以下的分类帮助不大。 相似文献
13.
BOSA E. OKOLI F.L.S. OMOTOYE OLORODE 《Botanical journal of the Linnean Society. Linnean Society of London》1983,87(3):263-271
Cytogenetic studies in the Andropogon gayanus—A. tectorum complex (Granimae). Studies on the morphology, karyotype and meiotic behaviour of collections of Andropogon gayanus [2 n = 40), A. tectorum (2 n = 20,30) and their hybrids, obtained by both open pollination and controlled crosses, have been made. The chromosome number of 2 n = 30 for A. tectorum is new. Karyotypic analyses of the species and the preponderance of trivalents at diakinesis in the triploid and aneuploid hybrids show that considerable homology exists between the genomes of the two species. The evolutionary relationship between the two species and the probable origin of tetraploid A. gayanus are discussed. 相似文献
14.
Olof Ryding 《Nordic Journal of Botany》1991,11(3):317-321
A study of the variation within the tropical African taxon Trifolium burchellianum ssp. johnstonii , including var. oblongum , is made on the basis of herbarium material and cultivated material. The chromosome numbers 2n = 48 and 2n = 96 were counted in the collections of var. johnstonii and var. oblongum respectively. In most other material, the chromosome number has been estimated from the size of the pollen grains and guard cells. Var. johnstonii was found to have both 2n = 48 and 2n = 96 and var. oblongum was found only to have 2n = 96. Var. oblongum and var. johnstonii with 2n = 96 are found to have complementary distributions, while the distribution of var. johnstonii with 2n = 48 is found sympatric with all the 2n = 96 material. The sterility barriers are persumed to have become weakened at the higher ploidy level, and gene flow is presumed to explain the continuous variation between the two varieties. The origin of var. oblongum is also discussed. 相似文献
15.
粗根韭的核型分化研究 总被引:5,自引:0,他引:5
对葱属粗根韭的3个地方居群的核型分析结果表明,3个居群的核型表现出很大的差异。西藏
达孜居群为2n=2x=20=4m+10sm+2t(2SAT)+4T;四川乡城居群为2n=2x=20=10sm+6t
(2SAT)+4T;四川理县居群为2n=2x=20=6m+1Osm+2t(2SAT)+2T。虽然它们之间在核型上存
在差异,但除达孜居群的植株较矮小外,3个居群的植物在形态上却非常一致。理县居群的核型被认为
是原始类型,由它通过染色体结构变异,分别演化出更不对称的达孜居群和乡城居群。葱属中,目前只
发现4个种的染色体基数为10,除本种外其余3种分别是A.decipiens Fisch.;A.kujukense Vved.和
A.chelotum Wendelbo。根据这4个种的核型特征和分布格局,基数10可能有不同的起源,至少粗根韭
的起源与其余3种不同,而且起源最晚。粗根韭的核型特征及它与染色体基数为11的宽叶韭A.hook-
eri Thwaites在核型上的相似性,表明它们很可能共同起源于基数为10但现已绝灭的祖先种。此外,还探讨了该祖先种的起源问题。 相似文献
16.
S. Frederiksen 《Nordic Journal of Botany》1991,11(3):271-285
Eremopyrum (tribe Triticeae) is revised and 4 species are recognized: E. triticeum (2n = 14), E. orientate (2n = 28), E. distans (2n = 14) and E. bonaepartis (2n = 14,28). A key and maps showing the distribution of the species are presented. The relationships within Eremopyrum , including the origin of the tetraploids, and the relationships between Eremopyrum and other genera of the Triticeae are discussed. 相似文献
17.
对桦木科桤木属自然分布于中国西南地区的4个种进行了细胞学研究,结果分别为:川滇桤木K(2n)=56=30m+24sm+2st;桤木K(2n)=56=38m+16sm+2M;蒙自桤木K(2n)=56=28m+26sm+2st;毛桤木K(2n)=56=42m+14sm;其中川滇桤木的核型属于2A型,其余均为2B型;上述种类染色体数目均为2n=56。4种材料的核型均为首次报道。 相似文献
18.
The chromosome numbers ofVeronica beccabunga subsp.abscondita (2n=18),V. anagallis-aquatica subsp.lysimachioides (2n=18),V. anagallis-aquatica subsp.michauxii (2n=36), and of a presumable hybridV. poljensis × V. anagalloides (2n=36) are new for the relevant taxa. — A new number was found forV. anagalloides subsp.heureka (2n=18). The other counts, ofV. scardica (2n=18),V. anagalloides subsp.anagalloides (2n=18), andV. anagallis-aquatica subsp.oxycarpa (2n=36) agree with earlier findings.—Data from the literature have been critically evaluated, in some cases the relevant vouchers have been checked and, where needed, the original determinations have been revised. For several taxa, comments concerning their systematics and remarks on their distribution in Turkey are given. 相似文献
19.
本文报道了我国蒿属6种的染色体核型,它们的核型公式分别为:牡蒿(ArtemisiajaponicaThunb.)2n=18=12m+6sm(2SAT);西南牡蒿(A.parvifloraBucb.-Ham.exRoxb.)2n=36=30m+4sm+2st(6SAT);多花蒿(A.myrianthaWall.exBess.)2n=36=30m+6sm:牛尾蒿(A.dubiaWall.exBess.)2n=36=28m+8sm(2SAT);野艾蒿(A.lavandulaefoliaDC.)2n=54=42m+12sm;荚毛蒿(A.velutinaPamp.)2n=54=36m+18sm. 相似文献
20.
A karyological study of 15 taxa ofScorzonera L. from the Iberian Peninsula has been made. The chromosome numbers found inS. hispanica var.pinnatifida, S. baetica, S. reverchonii, S. angustifolia, S. laciniata var.calcitrapifolia and var.subulata (2n = 14) are new. Diploid cytotypes with 2n = 14 and 2n = 12 prevail, andS. hispanica var.crispatula is the only taxon which exhibits autopolyploidy (2n = 14, 28). x = 7 is considered to be the base chromosome number within the genus, with x = 6 being derived from it by translocation. This and detailed karyotype analyses allow to group the Iberian Peninsula species ofScorzonera into three groups. 相似文献