华南地区3种兔儿风属植物(菊科-帚菊木族)的细胞学研究

首次报道了华南地区兔儿风属(Ainsliaea DC.)(菊科-帚菊木族Asteraceae-Pertyeae)3种植物共4个居群的染色体数目和核型。其中长穗兔儿风(A.henryi Diels)的染色体数目为2n=24,核型公式为2n=16m+8sm;三脉兔儿风(A.trinervis Y.C.Tseng)的染色体数目为2n=26,核型公式为2n=16m+10sm;莲沱兔儿风(A.ramosa Hemsl.)2个居群的染色体数目均为2n=26,核型公式为2n=26=22m+4sm。所有居群的染色体由大到小逐渐变化,核型没有明显的二型性。这些结果表明兔儿风属植物确有x=12和x=13两个基数,其中x=13可能是该属的原始基数。     

风毛菊属5种植物的核型分析

采用常规压片法,对风毛菊属(Saussurea)5种植物的染色体数目和核型类型进行分析。结果表明:大耳叶风毛菊(S.macrota)核型公式为2n=2x=26=10m+12sm+4st,属2A型;长梗风毛菊(S.dolichopoda)核型公式为2n=2x=26=14m+8sm+4st,属2A型;川陕风毛菊(S.licentiana)核型公式为2n=2x=28=12m+16sm,属2B型;杨叶风毛菊(S.populifolia)核型公式为2n=2x=28=6m+18sm+4st,属2B型;尾叶风毛菊(S.caudata)核型公式为2n=2x=30=14m+14sm+2st,属2A型。这5种风毛菊属植物中,除大耳叶风毛菊染色体数目和核型类型与前人报道的一致外,其余4种植物的染色体数目和核型类型均为首次报道,并在川陕风毛菊中发现1对B染色体。     

新疆猪毛菜属4种植物核型分析及进化研究

采用常规压片法,对钠猪毛菜、准噶尔猪毛菜、小药猪毛菜和薄翅猪毛菜等4种新疆猪毛菜属植物的染色体核型进行了分析,并对已报道的12种新疆猪毛菜属植物核型进行了比较.结果表明:(1)钠猪毛菜体细胞染色体数2n=2x=18=12m+6sm,准噶尔猪毛菜、小药猪毛菜体细胞染色体数为2n=2x=18=18m,该3种均属于1A型;薄翅猪毛菜体细胞染色体数为2n=2x=54=50m+2sm+2st,属2A型;(2)12种新疆猪毛菜属植物核型比较结果证明,猪毛菜属植物的染色体基数为9,钠猪毛菜、准噶尔猪毛菜和小药猪毛菜均为二倍体,薄翅猪毛菜为六倍体,钠猪毛菜和准噶尔猪毛菜具有随体.准噶尔猪毛菜、小药猪毛菜、薄翅猪毛菜属植物的核型均属于首次报道.     

横断山及邻近地区八种菊科植物的染色体数目及核型

对横断山及邻近地区风毛菊属(Saussurea)、帚菊属(Pertya)和针苞菊属(Tricholepis)的8种菊科植物进行细胞学研究,其中异叶帚菊(Pertya berberidoides)(2n=2x=32=28m+4sm)、针苞菊(Trichole-pis furcata)(2n=2x=32=16m+ 16sm)、中甸风毛菊(Saussurea dschungdienensis)(2n=2x=30=30m+Bs)、丽江风毛菊(S.likiangensis)(2n 2x=32=26m+6sm)、倒齿风毛菊(S.retroserrata)(2n=2x=32=14m+18sm)和显梗风毛菊(S.peduncularis)(2n=2x=36=26m+ 10sm)为首次报道染色体数目和核型,长毛风毛菊(S.hieracioides)和三角叶风毛菊(S.deltoidea)的核型公式分别为:2n=4x=64=30m+34sm和2n=2x=34=22m+ 12sm,与前人报道的一致.8种植物中,除中甸风毛菊和异叶帚菊的核型不对称性为1B型外,其余6种的核型不对称性均属于2B型;在中甸风毛菊中首次发现B染色体.结合现有的细胞学资料分析表明,风毛菊属和帚菊木族的染色体数目存在变异,并且存在明显的非整倍性;此外,分布于横断山区的风毛菊属植物仪有两种倍性(二倍体和四倍体),而且多倍化并不占主导地位.     

黑藻属植物的核型分析

本文以根尖细胞为材料,观察了黑藻属Hydrilla植物的染色体核型。 它由两群染色体组成：1—5 为长染色体,6—8 为短染色体。 染色体基数x=8。轮叶黑藻Hydrilla verticillata(L. f.)Royle为二倍体;染色体数目为2n=2x=16; 雌雄之间既无染色体数目的差别,也无异型染色体存在;核型公式为2n=2x=16＝6m+6Sm十4St。 罗氏轮叶黑藻Hydrilla verticillata var．roxburgbii Casp系同源三倍体; 染色体数目为2n=3x=24; 核型公式为2n=3x=24=9m+9Sm+6St。     

沙芥属植物染色体数及核型分析

以沙芥属植物根尖为材料,采用常规压片法,对其染色体数及其核型进行分析,结果表明:本属植物间期核特征为前染色体核型;染色体均为二倍体,沙芥染色体数为2n=2x=22,基数为x=11,宽翅沙芥、斧形沙芥、距果沙芥和齿冠沙芥染色体数为2n=2x=20,基数为x=10;染色体有亚中部着丝点染色体(sm)和中部着丝点染色体(m)2种;沙芥、距果沙芥属于2A型,宽翅沙芥、斧形沙芥、齿冠沙芥属于1A型,本属植物的核型均为首次报道。根据核型特征进行聚类分析,将染色体数为2n=2x=20的沙芥属4种植物分为两类:第一类距果沙芥;第二类包括宽翅沙芥、斧形沙芥、齿冠沙芥。     

横断山高山冰缘带5种黄耆属植物的核型分析

通过常规植物染色压片法对采自横断山高山冰缘带地区豆科黄耆属（Astragalus）5种植物进行了染色体数目及核型分析。结果显示：川西黄耆（A. craibianus Simps.）、无茎黄耆（A. acaulis Baker）、梭果黄耆（A. ernestii Comb.）、东俄洛黄耆（A. tongolensis Ulbr.）为二倍体,窄翼黄耆（A. degensis Ulbr.）为四倍体,所有物种的染色体基数均为x=8;川西黄耆的染色体核型公式为2n=2x=16=6sm+10m,为2A型,无茎黄耆的染色体核型公式为2n=2x=16=2sm+14m,为2A型,梭果黄耆的染色体核型公式为2n=2x=16=2sm+14m,为2A型,窄翼黄耆的染色体核型公式为2n=4x=32=4sm+28m,为1A型,东俄洛黄耆的染色体核型公式为2n=2x=16=2st+2sm+12m,为2A型。已报道横断山的黄耆属物种均为二倍体,而本研究首次发现了四倍体种,研究结果补充了横断山高山地区黄耆属植物染色体的基础资料,同时为该区域的植物系统分类及属内植物进化研究提供了细胞分类学上的参考。     

国产6种铁线莲的染色体研究

本文报道了我国产铁线莲属Clematis L.6个种的染色体研究结果。其中2种(灌木铁线莲和粗柄铁线莲)的染色体数目及核型为首次报道,1种(女萎)为国内首次报道。6种均为二倍体(2n=2x=16),基数为8(x=8)。本属基数为8的二倍体核型公式概括如下: 2n=2x=16=10m+2st+(4或2或0)st[(2或0)SAT]+(0或2或4)t[(2或4)SAT]核型特征是:中型(4—10.5μm);1—5号为m染色体,6号为st染色体,7—8号染色体变异于st和t之间;具1或2对随体(SAT)染色体。该属染色体的演化处于两种水平:数目变化(包括多倍化和非整倍体变化)和结构变异。后者是本属物种形成的主要方面。3种具异形同源染色体,这种杂合性可能是缺失所致。     

三白草核型分析

本文对三白草的核型进行分析。结果表明,三白草染色体基数为X=11,二倍体2n=22;而三白草科的原始染色体基数为X=11,三白草属与祖先型的是一致的,是科中最原始的一个分类群。核型公式为:2n=2x=22=2m+8sm+1st,核型为3B。     

唇形科独一味属和五种糙苏属植物的核形态研究

首次报道了唇形科Lamiaceae独一味属Lamiophlomis和五种糙苏属Phlomis植物的染色体数目和核型。它们的间期核均属球状前染色体型,有丝分裂前期染色体均为中间型。中期染色体核型公式如下:独一味L.rotata,2n=2x=22=18m 4sm;糙苏P.umbrosa,2n=2x=22=22m;裂萼糙苏P.ruptilis,2n=2x=22=22m;假秦艽P.betonicoides,2n=2x=22=22m;黑花糙苏P.melanantha,2n=2x=22=22m(2sat);糙毛糙苏P.strigosa,2n=6x=66=60m 6sm;染色体基数均为x=11。这表明独一味与糙苏属的糙苏组sect.Phlomoides植物具有相同的染色体基数,反映出两者较为密切的系统演化关系,推断独一味很可能是糙苏属的一个种。     

凤仙花近缘种间核型分析与叶表皮微形态研究

为探究凤仙花近缘种植物的细胞学和微形态学方面的亲缘关系,该文选取荔波凤仙花(Impatiens liboensis)及近缘种赤水凤仙花(I.chishuiensis)和管茎凤仙花(I.tubulosa)的根尖和叶表皮为实验材料,采用体细胞染色体常规压片法和叶表皮光学显微镜观察法对凤仙花近缘种植物进行染色体及叶表皮特征研...     

角堇与大花三色堇染色体核型分析

以2份角堇与4份大花三色堇自交系为试验材料,采用染色体常规压片方法,观察和分析了它们的细胞染色体数目、相对长度、平均臂比等核型指标,以明确两种植物细胞学特点,为分类以及育种提供理论依据。结果表明:(1)2份角堇自交系染色体数目均为2n=2x=26,染色体基数为x=13,染色体核型公式分别为2n=2x=26=8m+12sm+6st、2n=2x=26=4m+16sm+6st,核型不对称系数为67.20%~70.10%,核型分类均属于3B。(2)4份大花三色堇自交系均为四倍体,其中2份(EYO-1-2-1-4、DSRFY-1-1-2)染色体数目为44,核型公式为2n=4x=44=4m+16sm+6st、2n=4x=44=16m+24sm+4st;2份(G10-1-3-1-4、XXL-YB-1-1-1-1)染色体数目为48,核型公式分别为2n=4x=48=8m+20sm+20st、2n=4x=48=4m+36sm+8st,核型不对称系数为66.74%~71.77%,核型分类属于2B、3B。     

Additional chromosome numbers inPelargonium (Geraniaceae)

Mitotic chromosome counts were made from field collected and subsequently cultivated plants of 61Pelargonium species from 14 sections. The 33 new results are presented. 47 of the species have a basic number of x = 11, nine spp. of x = 9 and five spp. of x = 8. 17 spp. are polyploid. In two sections species with different basic numbers occur, which is of interest for the subgeneric classification. The size of the chromosomes varies between the investigated species. Most but not all species with x = 11 have short, those with x = 8, 9 large, and only exceptionally short chromosomes. Within sections chromosome size is not always uniform. The relationship between the different basic chromosome numbers is discussed.     

Cytological variation and evolution withinPelargonium sectionHoarea (Geraniaceae)

Chromosome numbers of 65 species of sect.Hoarea have been determined. These show three basic chromosome numbers, x = 11, 10 and 9. Only a few species are tetraploid. In five species both diploid and tetraploid cytotypes are reported. Several cases of deviations in chromosome numbers and cytological abnormalities were found, most of these being related to the presence of B chromosomes that occur in eight species. Evidence is presented to suggest that the basic chromosome numbers of x = 10 and x = 9 are derived from x = 11 by centric fusion. Although variation in basic chromosome number withinPelargonium has been the subject of detailed study, this is the first time that evidence has been found for a mechanism of change in basic number, that of centric fusion by Robertsonian translocation. For the species of sect.Hoarea with x = 9, where the evidence for Robertsonian translocation is greatest, this process has probably taken place quite recently. In contrast to results from other sections of the genusPelargonium, the three different basic numbers of sect.Hoarea do not contradict its delimitation as a natural taxon.     

A cytological study ofPelargonium sect.Eumorpha (Geraniaceae)

The chromosome numbers of seven species ofPelargonium sect.Eumorpha have been determined from material of known wild origin, and karyotypic comparisons have been made. Within the section there is variation in basic chromosome number (x = 4, 8, 9, 11), variation in chromosome size, and two species have polyploid races. The three species with chromosome numbers based on x = 11 have the smallest chromosomes (1.0–1.5 µm); chromosomes are larger (1.0–3.0 µm) in the other species.P. elongatum has the lowest chromosome number in the genus (2n = 8).P. alchemilloides is exceptional in that it has four cytotypes, 2n = 16, 18, 34 and 36, and the form with 2n = 36 has large chromosomes (2.0–5.0 µm). Evidence from a synthesized hybrid suggests thatP. alchemilloides with 2n = 16 may be of polyploid origin. The three species based on x = 11 appear to be more closely related to species from other sections ofPelargonium that have the same basic chromosome number and small chromosome size, rather than to other species of sect.Eumorpha.     

中国西南地区6种植物的核型研究及其系统学意义

采用植物细胞学研究方法对主要采自中国西南地区横断山的6种植物:扁核木(Prinsepia utilis)、小叶金露梅(Potentilla parvifolia)、峨眉繁缕(Stellaria omeiensis)、金铁锁(Psammosilene tunicoides)、山卷耳(Cerastium pusillum)和独尾草(Eremurus chinensis)进行染色体数目和核型研究。研究表明:(1)6个种的核型公式和不对称性如下:扁核木2n=2x=30=1M+20m+9sm,2A;小叶金露梅2n=2x=28=21m+7sm,2B;峨眉繁缕2n=8x=72=1M+71m,1B;金铁锁在同居群下有倍性变化,2n=2x=14=14m,1A和2n=4x=28=28m,1A;山卷耳2n=2x=24=24m(2sat),1A;独尾草2n=2x=14=2m+2sm+8st+2t,4B。(2)讨论了染色体资料在这些物种分类和系统上的意义,支持扁核木为李亚科下的扁核木属;位于委陵菜属木本系的小叶金露梅主要以二倍体和四倍体为主,而草本系的委陵菜属植物多为多倍体。(3)该研究首次报道峨眉繁缕为八倍体,是繁缕属发现的最高倍性的物种;对比金铁锁属与蝇子草属的染色体研究发现,金铁锁属可能是由它们的共同祖先通过非整倍化产生;该研究首次发现山卷耳存在染色体数目2n=24的情况,且有1对随体;独尾草的研究进一步证明该物种可能为二型核。     

半蒴苣苔属植物染色体制片优化及染色体数目和倍性研究

染色体数目和倍性是系统与进化生物学和遗传学研究中十分重要的基础信息。为探索半蒴苣苔属染色体制片的适宜条件以及染色体数目的进化模式及其与物种的进化关系，该研究基于半蒴苣苔属染色体数目的进化历史，并根据该属植物具有叶片扦插繁殖的特性，采用叶片水培生根法获取半蒴苣苔(Hemiboea subcapitata)、弄岗半蒴苣苔(H.longgangensis)、龙州半蒴苣苔(H.longzhouensis)、江西半蒴苣苔(H.subacaulis var.jiangxiensis)、华南半蒴苣苔(H.follicularis)和永福半蒴苣苔(H.yongfuensis)6种植物的根尖材料，分析不同实验条件对染色体制片效果的影响，对染色体制片实验的条件进行优化及染色体计数，结果表明：(1)9:30—10:00取材，解离10 min以及染色15 min为半蒴苣苔属染色体制片的适宜条件。(2)上述6种半蒴苣苔属植物均为二倍体，染色体数目均为32(2n=2x=32)。(3)除个别物种染色体数目有变化以外，该属大部分物种染色体数目可能为2n=2x=32且染色体数目变化可能是非整倍化的作用，与物种进化没有明...     

First report of chromosome numbers and karyotypes of two monotypic genera endemic to eastern Asia: Brachystemma (Caryophyllaceae) and Craspedolobium (Fabaceae)

The chromosome numbers and karyotypes of Brachystemma and Craspedolobium, two monotypic genera endemic to eastern Asia, are reported here for the first time. The somatic chromosome numbers are 2n=40 for Brachystemma calycinum and 2n=22 for Craspedolobium unijugum. A karyotype of 2n=2x=40=28m+12sm was found in B. calycinum and that of 2n=2x=22=12m+10sm in C. unijugum, both of them have a moderately symmetrical karyotype type 2B and small‐sized chromosomes. Brachystemma has a unique basic chromosome number in Alsinoideae, which may support its isolated taxonomic position. As do some morphological characters, the basic chromosome number x=11 suggests that Craspedolobium belongs in the Millettioid clade.     

Cytotaxonomy of Dubyaea glaucescens (Compositae–Cichorieae)

Recent molecular phylogenetic analyses indicate that Dubyaea glaucescens (Compositae–Cichorieae) should be transferred to the genus Faberia as F. glaucescens. Here, we present cytological evidence for this transfer. Dubyaea glaucescens comprises two ploidy levels, 2n = 34 (diploid) and 2n = 51 (triploid), making the basic chromosome number x = 17. The chromosomes vary in length from 5.82 μm to 2.11 μm, and the karyotypes are 2n = 20m + 14sm (3sat) for the diploid cytotype and 2n = 30m + 21sm (3sat) for the triploid cytotype. Karyological characters of D. glaucescens, including chromosome number, size, morphology, and karyotype asymmetry, all agree remarkably with those reported previously in Faberia, but are distinct from those in other species of Dubyaea. The transfer of D. glaucescens to Faberia is thus strongly corroborated.     

风毛菊属6种植物的核型分析

采用常规压片技术对分布于横断山区菊科(Compositae)风毛菊属(Saussurea DC.)的6种植物进行染色体数目和核型分析。结果表明:尖苞雪莲（S.polycolea var.acutisquama）核型公式为:2n=2x=32=20m+12sm,属2B型;球花雪莲核（S.globosa）型公式为:2n=2x=34=16m+18sm,属2B型;重齿风毛菊(S.katochaete)核型公式为:2n=2x=32=8m+18sm+6st,属3B型;柱茎风毛菊(S.columnaris)核型公式为:2n=2x=32=24m+8sm,属2B型;禾叶风毛菊(S.graminea)核型公式为:2n=2x=28=8m+18sm+2st,属3B型;长毛风毛菊(S.hieracioides)核型公式为:2n=2x=32=12m+16sm+4st,属2B型。6个种染色体中均未发现随体。其中尖苞雪莲和柱茎风毛菊染色体为首次报道。