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1.
The present paper reports the chromosome numbers and karyotypes of eight species of Sect. Rhiziridium in Allium (Liaceae). The materials were all collected from their natural populations in east Inner Mongolia, China. The karyotype analysis is made on the basis of Li et al. (1985).The results are as follows (for chromosomes parameters, voucher specimens and localities, see Table 1 and Plate 1--2 the idiograms of the eight species in Fig. 1): (1) Auium leucocephalum Turcz. The somatic chromosome number and karyotype of this species is 2n=16=12m=2sm+2st (2SAT), in Stebbinsl(1971) kayotype classification, which belongs to 2A (Plate 1: 1; Fig. 1: 1). The range of chromosome relative length varies between 8.90--15.55%. Two small satellites are attached to the short arms of the 8th pair of chromosomes. (2) A. strictum Schrader has 2n (4x) =32=16m+4sm+12st, belonging to 2B (Plate 1: 2 & Fig. 1: 2). Satellites were not observed., and the range of chromosome relative length is between 3. 67-11.00%. (3) A. ramosum L. 2n=16=14m+ 2st (2SAT), belonging to 2A (Plate 1: 3 & Fig. 1: 3), Two small satellies are attached to the short arms of the 8th pair of chromosomes. The range of chromosome relative length is between 9.17-16.39%. The chromosome number and karyotype of this species are in accordancewith those reported by Li et al. (1982) with the material from Jinshan, Beijing. (4) A. bidentatum Fisch. ex Prokh. 2n (4x) =32=24m+4sm+4T, belonging to 2B (Plate 1: 4 & Fig. 1: 4). Satellites were not observed. A small median B-chromosome was found in root-tip cells of the population growing in sandy soil, and it is the first discovery (Plate 2: 9). The species has terminal chromosomes, which are seldom seen in Sect. Rhiziridium. The range of chromosome relative length is between 3.32—9.06%. (5) A. tenuissimu L. 2n=16= 10m+4sm+2st(2SAT), belonging to 2B(Plate 1:5 & Fig. 1:5). Two large satellites are attached to the short arms of the 8th pair of chromosome. The range of chromosome relative length is between 8.27--17.56%. (6)A. anisopodium Ledeb. 2n = 16 = l2m +2sm + 2st (2SAT), belonging to 2A (Plate 2:7 & Fig. 1: 7). Two large satellites are attached to the short arms of the 8th pair of chromosomes. In somatic cells of some plants of this species, a small submedian B-chromosome was found (Plate 2: 10, 11). The range of chromosome relative length is between 8.05-17.08 %. (7) A. anisopodium Ledeb. var. zimmermannianum (Gilg) Wang et Tang 2n (4x)=32=24m+4sm+4st( 4SAT), belonging to 2A (Plate 1: 6 & Fig. 1: 6). Four large satellites are attached to the short arms of the 15 and 16th pairs of chromosomes. The range of chromosome relative length is between 4.45--8.35%. This variety is similar to A. anisopodium Ledeb. in morphological characters, and their karyotype formulas are also very similar. The present authors consider that the variety is an allotetraploid derived from A. anisopodium Ledeb. (8) A. condensatum Turcz. 2n=16=14m+2st (2SAT), belonging to 2B (Plate 2:8 & Fig. 1:8). Two. small satellites are attached to the short arms of the 6th pair of chromosomes. In a few individuals of this species median (M) B-chromosome was discovered, and the number is stable (Plate 2: 12). The range of chromosome relative length is between 7.64--17.07%. In short, the chromosome numbers of the species studied in the present work are found to be 2n=16 or 32, and the karyotypes belong to 2A or 2B, highly symmetrical. The karyotypes of Chinese materials of these species are mostly reported for the first time. Threespecies have B-chromosomes.  相似文献   

2.
中国山茶属4种2变种核型研究   总被引:11,自引:0,他引:11  
李光涛  梁涛   《广西植物》1990,10(3):189-197
本文采用去壁低渗法研究了我国山茶属植物4种2变种的核型。根据Levan等的命名系统,各个种的核型可简式为大理茶2n=20m+2m(SAT)+8sm;勐腊茶2n=20m+2m(SAT)+6sm+2sm(SAT);德宏茶2n=20m+8sm+2sm(SAT);苦茶2n=20m+9sm+1sm(SAT);茶2n=18m+2m(SAT)+12sm;白毛茶2n=18m十2m(SAT)+9sm+1sm(SAT)。这些种都是二倍体种(2n=2x=30),未发现多倍体。在勐腊茶核型中发现2个超数染色体(B-chromosome)。核型的不对称性表明,这些种均属于Stebbins核型分类的2A型核型。这些种在“随体数目和位置,最长染色体与最短染色体之比,臂比大于2:1的染色体比例,着丝点端化值,染色体绝对长度”方面的变异是清楚易见的。核型的变异表明,这些种的染色体进化顺序为大理茶—→勐腊茶—→德宏茶—→普洱茶—→白毛茶—→苦茶—→茶。这一结果与张宏达提出的山茶属植物的分类系统基木吻合。本文还讨论了山茶属植物核型的杂合性和多态性。本文中勐腊茶、德宏茶、苦茶的染色体数目和核型及大理茶的核型为首次报道。  相似文献   

3.

7种铁线莲的染色体研究

  总被引:5,自引:0,他引:5  
本文描述了我国产毛茛科铁线莲属的7个种的染色体数目和形态。其核型公式分别为:芹叶铁线莲和宽芹叶铁线莲为2n(2x)=16=10m+6st(2SAT);黄花铁线莲和棉团铁线莲及山木通为2n(2x)=10m+4st+2t(2SAT);圆锥铁线莲为2n(2x)=32=20m+8st(2SAT)+4t(2SAT);吴兴铁线莲为2n(4x)=32=20m+6st(4SAT)+6t(4SAT);本文还讨论了一些种的分类问题。  相似文献   

4.
The karyotypes of 10 species of the Liliaceae from the Qinling Range are reported as follows. I. Polygonatum Mill. (1) P. odoratum ( Mill. ) Druce was found to have the karyotype 2n=20=12m+8sm ( Plate 3, Fig. I), which belongs to Stebbins’ (1971) karyotype classification 2B. The chromosomes range from 3.88 to 11.26μm in size. Table 2 shows the karyotypes and number fundamentals (N.F.) of 13 materials from 12 different localities. The N. F. of these materials can be classified into two groups: N.F. =36 and N.F.=40, besides one (N.F. =38) from Beijing. N. F. =36 covers all the materials with 2n= 18 which have relatively symmetrical karyotypes ( all consisting of m and sm chromosomes), one with 2n=20 (10m+6sm+4st) and one with 2n=22 (14m+8st). N.F. =40 include four materials with 2n= 20 (all of m and sm chromosomes ) and 3 with 2n= 22 (10m+ 8sm+ 4st). ¥ It is considered that there are two original karyotypes, 2n= 18 with N. F. = 36 and 2n= 20 with N.F. =40, which are relatively symmetrical. All the more asymmetrical karyotypes with some st chromosomes have probably evolved from the symmetrical karyotypes without st chromosomes by centric fission. (2) P. zanlanscianense Pamp. has the karyotype 2n=30=18m(2SAT) + 4sm+ 6st+ 2t (Plate 1, Fig. 1) which belongs to 2C. The chromosomes range from 2.16 to 9.76μm. ¥ II. Asparagus filicinus Buch.-Ham. ex D.Don. The karyotype of this species is 2n = 16= 8m(2SAT )+ 6sm + 2st (Plate 1, Fig. 1 and Table 3 ) , which belongs to 2B. The chromosomes range from 2.33 to 5.30μm. Most species in Asparagus, including A.Filicinus, are reported to have basic number x= 10, and therefore 2n= 16 is a new chromosome number for A.filicinus. EL-Saded et.al.(1972) gave a report of n=8 for A. stipularis from Egypt, while Delay (1947) reported 2n = 24 for A. trichophyllus and A. verticillatus, Sinla(1972 ) gave a report of 2n=48 for A.racemosus. It is certain that there are two basic numbers in the genus Asparagus. III. Cardiocrinum giganteum (Wall.) Makino was found to have the karyotype 2n=24=4m+8st+12t (Plate 1, Fig. 1 ), which belongs to 3B. The chromosomes range from 8.71 to 20.24μm. IV. Smilax discotis Warb. was shown to have the karyotype 2n=32=4m+22sm+4st (2SAT)+2t (Plate 1, Fig. 1 and Table 3), which belongs to 3C. The first pair is much longer than others. The chromosomes range from 1.79 to 9.21μm. The chromosome number and karyotype of S. discotis are both reported for the first time. V. Reineckia carnea (Andr.) Kunth is of the karyotype 2n=38=28m+10sm (Plate 2, Fig. 1 ), which belongs to 2B. The chromosomes range from 5.65 to 12.75μm. VI. Tupistra chinensis Baker was found to have the karyotype 2n=38=25m+ 13sm (Plate 2, Fig. 1), which belongs to 2B. The chromosomes range from 8.11 to 23.82μm. A pair of heterozygous chromosomes is arranged at the end of the idiogram. The eighth pair possesses an intercalary satellite. Huang et al. (1989) reported the karyotype of T. chinensis from Yunnan as 2n = 38 = 24m+ 14sm without any intercalary satellite. Nagamatsu and Noda (1970) gave a report on the karyotype of T. nutans from Bhutan, which consists of 18 pairs of median to submedian chromosomes and one pair of subterminal chromosomes. And one pair of submedian chromosomes possess intercalary satellites on their short arms. VII. Rohdea japonica (Thunb) Roth. was found to have the karyotype 2n=38=30m+6sm+2st ( Plate 2, Fig. 1), which belongs to 2B. The chromosomes range from 7.94 to 18.29μm. Nagamatsu and Noda (1970) reported that the karyotype of R.japonica from Japan was the same as that of Tupistra nutans from Bhutan. But we have not discov ered any chromosome with an intercalary satellite. VIII. Hosta Tratt. (1) H. plantaginea (Lam.) Aschers was shown to have 2n=60. The 60 chromosomes are in 30 pairs,which can be classified into 4 pairs of large chromosomes (7.32- 8.72μm ), 3 pairs of medium-sized ones (4.72-5.60μm), and 23 pairs of small ones (1.40-3.64μm), (Plate 3 ,Table 4 ). The karyotype of H. plantaginea is reported for the first time. (2) H. ventricosa (Salisb.) Stearn was counted to have 2n=120, The 120 chromosomes are in 60 pairs, which can be classified into 8 pairs of large chromosomes (7.00- 8.40μm ), 6 pairs of medium-sized ones(4.40- 6.15um ), 46 pairs of small ones (1.20- 3.85μm), (Plate 3, Table 4). Based on the karyotypes of H. plantaginea and H. ventricosa, the latter is probably a tetraploid in the genus Hosta. Kaneko (1968b) gave a report on the karyotype of H. ventricosa, which is of8 pairs of large chromosomes, 4 pairs of medium-sized and 48 pairs of small ones.  相似文献   

5.
The present paper deals with the karyotypic analysis of Taxodium ascendens Brongn. The somatic chromosomes in root-tip cells of the plant are found to be 2n =22, all with median and submedian constrictions. A character of the karyotype is that the chromosome 10 has a long kinetochore region (Plate 1:1). According to the terminology defined by Levan et al.[18], the karyotype formula is k(2n)=22=20m+2sm, which is different to Huang et Hsu’s[8] K(2n)=24=22m+2B(m). The karyotype belongs to “lA” of Stebbins’[24] karyotypic symmetry and is generally regarded as a relatively primitive one. The species’ chromosome complement is 2n=22=2L+8M2+12M1 according to I.R.L.difined by Kuo et al.[15] based on relative length. The lengths, arm ratios and types of chromosomes of the species are given in Table 1-I. The morphology of the chromosomes and the karyotype, are given in Plate 1:1. In the light of the works of Schlarbaum et al.[21] and Mehra et al.[17], K(2n)=22=20m (2SAT)+2sm and 2n=22=2L+6M2+14M1 are for T. distichum (L.) Rich. (see Table 1-II), K(2n)=20m+2sm and 2n=22=4L+4M2+12M1+2S for T. mucronatum Tenore (see Table 1-III, Plate 1:2), which belong to “lA” and “2A” respectively. The differences between three species in the ratio of the longest to the shortest chromosome, I.R.L. and the proportion of chromosomes with arm ratio >2 show that the karyotype of T. mucronatum is the most advanced and that of T. distichum the most primitive. The present author suggests that the sequence of evolutionary advance be T. distichum, T. ascendens, T. mucronatum. Based on the evidence from the karyotype analyses, ecology and geographical distribution (including fossil), the secondary center of genetic diversity (Fig. 1) and the probable evolu-tionary pattern (Fig. 2) of Taxodium are discussed.  相似文献   

6.
百合属4种植物的核型研究   总被引:1,自引:0,他引:1  
采用常规压片法对4种百合属植物野百合(L.brow n ii F.E.B row n ex M ie llez.)、兰州百合(L.d av id iiDuchartre var.un icolor(Hoog.)Co Hon.)、川百合(L.d av id ii Duchartre)、湖北百合(L.henry i B aker)进行了核型研究.结果表明,4种百合的染色体数目均为2n=24,核型除川百合为3A外,其余3种均为3B型.核型公式分别为:野百合2n(2x)=24=4m(2SAT) 2sm(2SAT) 4st 14t,兰州百合2n(2x)=24=2m(2SAT) 2sm 10st(2SAT) 8t 2T,川百合2n(2x)=24=2m(2SAT) 2sm 12st(3SAT) 8t,湖北百合2n(2x)=24=4m 18st 2t,其中湖北百合染色体核型为首次报道.通过比较发现,兰州百合与川百合的核型最为相似,亲缘关系相近;核型不对称性为兰州百合>川百合>野百合>湖北百合,以湖北百合的核型较为原始.  相似文献   

7.
对青藏高原高山冰缘地区毛茛科3种特有植物的核型进行了分析。它们的核型公式(K)、染色体相对长度组成(C.R.L.)和核型不对称系数(As.K%)分别为:青藏金莲花Troliuspumilusvar.tanguticus:K(2n)=6m+8sm(2SAT)+2st,C.R.L.=4L+4M2+4M1+4S,As.K%=63.57,核型属2B型;甘青乌头Aconitumtanguticum为K(2n)=6m+10sm,C.R.L.=4L+8M1+4S,As.K%=62.54,2B型;单花翠雀花Delphiniumcandelabrumvar.monanthum为K(2n)=6m+8sm+2st,C.R.L.=4L+4M2+4M1+6S,As.K%=64.34,属3B型。经同相关近缘种核型资料比较,青藏金莲花核型不对称性和进化程度比金莲花T.chinensis低;甘青乌头的核型不对称性和进化程度在其近缘类群(乌头组Sect.Aconitum)已报道的种之内最低;单花翠雀花核型不对称性和进化水平比翠雀组(Sect.Delphinastrum)已报道的展毛翠雀花D.kamaoensevar.glabrescens、  相似文献   

8.
Af finis C. hemsleyanae Franch. et Prain, sed caulibus scapiformibus, flori-lus flavis, majoribus, petalo antico basi saccato facile differt.Herba caespitosa circ. 30 cm longa. Rhizoma circ. 5-10 mm longum, 10 mm crassum, radicibus fibrosis, numerosis, fasciculatis. Caulis 1 usque numerosus, scapiformis, simplex, efoliolatus, interdum basi unifoliatus. Folia basalia numerosa, circ. 20 cm longa, petiolis circ. 15 cm longis basi marginato-expansis, plus minu-sve carnosulis, in sicco purpureo-brunneis, laminis circ. 5 cm longis 5-6 cm latis viridibus, subtus glaucescentibus, biternatis, pinnis brevipetiolulatis, pinnulis sessilibus vel subsessilibus, 2.5-3.5 cm longis, 2 - 3 cm latis bitripartitis, segmentis lanccolatis, saepe trilobatis.  相似文献   

9.
The present paper reports the chromosome numbers and karyotypes of five species in Polygonatum from Anhui of China. The materials used in this work are listed in Table 1, Photomicrographs of somatic metaphase and karyograms of the five species of Polygonatum in Plate 1, 2, 3, the idiograms in Fig. 1-11 and a comparison of the karyotype of them is provided in Table 2. The results are shown as follows: 1. Polygonatum odoratum (Mill.)Druce Two materials were examined. One from Mt. Huangshan, Anhui, has 2n= 16 = 10m (3sc)+ 6sm (Plate 1 :A, B). The idiogram is shown in Fig. 1. The chromosomes range in length from 2.85 to 8.85 μm, with the total length 48.63μm and the ratio of the longest to the shortest 3.11, The karyotype belong to Stebbins’(1971) 2B. The two chromosomes of the first pair have arm ratios 1.01 and 1.29 respectively, and The first pair has one chromosome carrying a satellite attached to the short arm, showing heterozyosity .The chromosome num ber of 2n= 16 in P. odoratum and its karyotype are reported for the first time. The other from Langyashan, Chu - xian, Anhui, is found to have 2n = 18 = 10m (Isc)+2sm+6st(2sc) (Plate 1: C, D). The idiogram is shown in Fig. 2. The chromosomes range in length from 2.43 to 8.29μm, with the total length 46.67µm and the ratio of the longest to the shortest 3.41. The karyotype is also of 2B. In a somatic chromosome complement the 2nd pair have one chromosome carrying a satellite attached to the long arm, showing heterozygosity. 2. Polygonatum filipes Merr. Two materials were examined. One from the Huangshan, Anhui is found to have two cytotypes: 2n= 16 and 2n=22. This paper reports one of them. The karyotype formula is 2n=22=8m+8sm(2sc)+6st(Plate 3: Q, R). The idiogram is shown in Fig. 3. The chromosomes range in length from 2.55- 5.85μm, with the total length 45.01 μm and the ratio of the longest to the shortest 2.29. The karyotype belongs to 3B. The other material from the Fangchang, Anhui, is shown to have four cytitypes: 2n= 14, 2n= 16, 2n=20 (Plate 3: W) and 2n=22. This paper reports two of them. Type I: the karytype formula is 2n=14=10m+4sm (Plate 3: S, T). The idiogram is shown in Fig. 5. The chromosomes range in length from 2.59 to 7.61μm, the total length 37.44μm and the ratio of the longest to the shortest is 2.94. the karyotype belongs to 2B. Type II :The karyotype formula is 2n=16=8m+4sm+4st (Plate 3: U, V). The idiogram is shown in Fig. 4. The chromosomes range in length from 2.65 to 8.21 μm, the total length 46.01 μm and the ratio of the longest to the shortest 3.10. The karyotype belongs to 2B. The chromosome numbers of 2n=20, 2n= 14 and 2n=22, and karyotype of 2n= 14 and 2n=22 in P. filipes are reported for the first time. 3. Polygonatum cytonema Hua Two materials were examined. One from the Langyashan, Chuxian, anhui, is found to have 2n = 18 = 8m (2sc)+ 6sm+ 4st (Plate 2: K, L). The idiogram is shown in Fig. 7. The chromosomes range in length from 3.41 to 9.21 μm, the total length 56.34μm and the ratio of the longest to the shortest is 2.70. The karyotype belongs to 2B. The other material from the Huangshan, Anhui, has two cytotypes: 2n=20 and 2n= 22. Type I: The karyotype formula is 2n= 20= 8m+ 6sm+ 6st (Plate 2: M, N). The idiogram is shown in Fig. 8. The chromosomes range in length from 1.75 to 5.03μm, with the total length 32. 91μm and the ratio of the longest to the shortest 2. 87. The karyotype is also of 2B. Type II: The karyotype formula is 2n=22=6m+ 8sm+4st+ 4t (Plate 2: O, P ). The idiogram is Shown in Fig. 10. The chromosomes range in length from 1.75 to 4.95 μm, with total length 35.05μm and the ratio of the longest to the shortest 2.83. The karyotype brlongs to 3B. 4. Polygonatum desoulayi kom. The material from Xuancheng, Anhui, is found to have karyotype 2n = 22 = 10m (2sc) + 6sm (lsc) + 6st ( Plate 2. I, J). The idiogram is shown in Fig. 6. The chromosomes range in length from 1.86 to 5.61μm, with the total length 41.98μm and the ratio of the longest to the shortest 3.02. The karyotype is also of 3B. The first pair has one chromosome carrying a satellite attached to the long arm, showing heterozygosity. The chromosome number and karyotype of Chinese material are reported for the first time. 5. Polygonatum verticillatum (L.) All. The material from the Langyashan, Chuxian, Anhui is found to have two cytotypes. Type 1: the karyotype formula is 2n = 18 = 2m+ 2sm+ 10st+ 2t+ 2T (Plate 1: G, H). The idiogram is shown in Fig.9. The chromosomes range in length from 1.86 to 4.03μm, with total length 28.28μm and the ratio of the longest to the shortest 2.17. The karyotype classification belongs to 3B. Type II: The karyotype formula is 2n=24=6m+4sm+12st+2T (Plate 1: E, F). The idiogram is shown in Fig. II. The chromosomes range in length from 2.01 to 5.03μm, with total length 41.36μm and the ratio of longest to shortest 2.50. The karyotype is also of 3B. The chromosome numbers and karyotypes of Chinese material are reported for the first time.  相似文献   

10.
The chromosome numbers and karyotypes of 7 species of Smilax L. in Liliaceae (s. 1.) are cytotaxonomically studied in this work. Their karyotypic characters, distinction between the species and the chromosomal basis of sexual differentiation are discussed. The karyotypes of most species are first reported. The results are shown as follows (see Tables 1-4 for the chromosome parameters and the karyotype constitution; Fig. 1 for their idiograms): 1. Smilax nipponica Miq. The species is one of the herbaceous species distributed in East Asia. Two karyotypes, 2n = 26(type A) and 2n = 32 (type B), are found in the species (Plate 1: 1-7). The karyotype of No. 88032 (uncertain of -L--M--S- sexuality) is 2n = 26 = 2m + 6st + 6m + 4sm + 6sm + 2st. The karyotype has 4 pairs of L chromosomes, of which the first three pairs are subterminal, and the 4th is median. The karyotype belongs to 3B. No. 88045 (the male) and No. 88046 (the female) have 2n = 32. Their karyotypes are basically uniform, and both are -L--M-- S 2n=32= 2m+4sm+ 2st+ 2m+4sm+ 6m+ 10sm + 2st, also with 4 pairs of L chromosomes, but the 2nd pair is median, and thus different from the type A. The karyotype belongs to 3B. The first pair of chromosomes of the male are distinctly unequal in length, with the D. V. (0.93) of relative length between them obviously greater than that of the female (0.1). The pair seems to be of sex-chromosomes. Sixteen bivalents (n= 16) were observed at PMCs MI of No. 88045 (Plate 1: 4). The major difference between the karyotypes A and B are greater relative length of L chromosomes in the type A than in the type B, and the increase of chromosome number in the karyotype B mainly due to the increase of st chromosomes. Nakajima (1937)reports 2n= 30 for S. hederacea var. nipponica (=S. nipponica, Wang and Tang, 1980). 2. S. riparia A. DC. This species is also herbaceous, distributed in East Asia. Thirty chromosomes were found in root-tip cells (uncertain of sexuality). The kar -L--M--S-yotype is 2n = 30 = 8st + 6sm + 2st + 6m + 6sm + 2st (Plate 3: 1, 5), consisting mainly of sm and st chromosomes. There are 4 pairs of L chromosomes which are all subterminal and the m chromosomes appear to fall all into S category. Though the karyotype belongs to 3B, it is less symmetrical than that of S. nipponica. The species is karyologically rather different from S. nipponica, therefore. The first pair of chromosomes of this material are unequal in length, and it may be a male. The karyotype of this species is first reported. 3. S. sieboldii Miq. The species is a thorny climbing shrub, distributed in East Asia. At PMCs All, 16 chromosomes (n= 16) were found (Plate 2: 6), in accordance with Nakajima's (1933) report for a Japanese material. 4. S. china L. This species, a thorny climbing shrub, is of a wide distribution range mainly in East Asia and Southeast Asia. Two karyotypes were observed in different populations. (1) The population from Xikou has 2n = 96(6x) = 20st+L- -M- 6t + 6sm + 12st + 52(S) (Plate 3:7), of which the first three pairs of chromosomes are terminal, different from those in the other species. The arm ratios of both L and M chromosomes are larger than 2.0, which resembles those of S. davidiana. (2) PMCs MI of the population from Shangyu shew 15 chromosomes (n 15). The hexaploid of the species is recorded for the first time. Hsu (1967,1971) reported 2n = 30 from Taiwai and Nakajima (1937) recorded n = 30 from Japan, which indicates that the karyotype of the species varies not only in ploidy, but also in number. 5. S. davidiana A. DC. The somatic cells were found to have 32 chromosomes, and PMCs MI shew 16 bivalents (Plate 2: 1-5). The karyotype is 2n = 32=-L- -M- -S 8st + 4sm + 4st + 8sm + 8st. The karyotype belongs to 3B, and is less symmetrical than those in herbaceous species. The D. V. (0.20) of relative length between the two homologues of the first pair is slightly larger in the male than in the female (0.14), and it is thus difficult to determine whether they are sexual chromosomes or not. 6. S. glabra Roxb. The species is a non-thorny climbing shrub, distributed in East Asia and Southeast Asia. 32 chromosomes were found in somatic cells. The -L- -M- - Skaryotype is 2n= 32= 8st + 10st+6sm+8st (Plate 3: 2, 6),with only 3 pairs of sm chromosomes (12, 13 and 16th). The karyotype is more asymmetric than that of S. davidiana, although it is also of 3B (Table 1). The karyotype is first reported for the species. 7. S. nervo-marginata Hay. var. liukiuensis (Hay.) Wang et Tang The variety has a relatively narrow distribution range, mainly occurring in eastern China. The chromosomal number of somatic cells is 2n= 32 (Plate 3: 3-4). The karyotype is -L- -M- -S 2n = 32 = 2sm + 6st + 2sm + 2st + 2m + 6sm + 12st, evidently different from that of S. glabra. The first pair of chromosomes are submedian, and much longer than the 2nd to 4th pairs. The ratio in length of the largest chromosome to the smallest one is 4.3. The symmetric degree is of 3C, a unique type. The karyotype of the species is reported for the first time. In Smilax, the known basic numbers are 13, 15, 16 and 17. The two herbaceous species distributed in East Asia have three basic numbers: 13, 15 and 16, while the woody species studied mainly have 16, with no 13 recorded. Mangaly (1968) studied 8 herbaceous species in North America and reported 2n=26 for them except S. pseudo-china with 2n=30. Mangaly considered that a probably ancestral home of Smilax, both the herbaceous and woody, is in Southeast Asia and the eastern Himalayas, and speculated that the ancestral type of Sect. Coprosmanthus is possibly an Asian species, S. riparia. The karyotypes of the two herbaceous species in East Asia consist mostly of sm and m chromosomes, whereas those for the North American species are all of st chromosomes. Based on the general rule of karyotypic evolution, i.e. from symmetry to asymmetry, his speculation seems reasonable. Researches on sex-chromosomes of Smilax have been carried out since 1930 (Lindsay, 1930; Jensen, 1937; Nakajima, 1937; Mangaly, 1968), and they are generally considered to be the largest pair, but there is still no adequate evidence. The result of our observation on S. nipponica may confirm that the first pair of chromosomes of this species is XY type of sex-chromosomes. Chromosomes of the genus are small and medium-sized, varying between 1-6 μm, slightly larger in herbaceous species than in woody ones, larger in the karyotype of 2n=26 than in that of 2n=32. Based on karyotype constitution of the above 5 species, the karyotype in the genus is characterized by 4 pairs of L chromosomes and 2-5 pairs of M chromosomes, and mostly st and sm chromosomes, and by rather asymmetrical 3B type. The degree of symmetry in the above 5 species is from Sect. Coprosmanthus to Sect. Coilanthus, and herbaceous species towoody ones.  相似文献   

11.
五种国产梾木属(广义)植物的核型   总被引:1,自引:0,他引:1  
对分布于我国的木来木属CornusL .(广义 ) 4个主要类群的 5种植物进行了细胞学研究。结果表明 ,这 5种植物的染色体数目和核型分别为 :灯台树C .controversaHemsl.2n=2 0 =2m 8sm 1 0st;红瑞木C .albaL .2n =2 2 =8sm 1 2st 2t;毛木来C .walteriWanger.2n =2 2 =8sm 1 4st(0_2SAT) ;山茱萸C .officinalisSeib .etZucc .2n =1 8=8m 1 0sm (0_2SAT) ;四照花 (变种 )C .kousavar.chinensisOsborn 2n =2 2=2sm 6st (0_2SAT) 1 4t  相似文献   

12.
本文报道了歪头菜V.unijugaA.Br.及其近缘种V.bifoliaNakai的核型。歪头菜V.unijugaA.Br.Zn=24=8m(4SAT)+12sm+4st和2n=12=2m(2SAT)+8sm+2st.RbifoliaNabai;2n=12=4m(2SAT)+6sm+2st.核型分析表明四倍体细胞型是一个同源多倍体。二倍体四倍体细胞型分布式样表明二倍体细胞型占据着较为偏北的区域。根据核型一致性,我们认为将V.bifolia仍处理为歪头菜的变种var.bracteata更为合适。  相似文献   

13.
鹅观草属五个类群的核型与进化   总被引:8,自引:0,他引:8  
蔡联炳  冯海生   《广西植物》1998,18(1):35-40
报道了鹅观草属5个类群的核型,即长芒鹅观草,核型2n=4x=28=22m+6sm(2SAT);短颖鹅观草,核型2n=4x=28=20m(2SAT)+8sm(2SAT);短柄鹅观草,核型2n=4x=28=22m(2SAT)+6sm;纤毛鹅观草,核型2n=4x=28=20m+8sm(4SAT);毛盘鹅观草,核型2n=4x=28=18m+6sm(4SAT)+4st。同时,通过核型重要性状的递变分析,揭示了鹅观草属5个类群的相对进化程度以及宏观分类中4个组的系统发育关系,表明鹅观草属的半颖组在系统发育中可能既派生了颖体短小的小颖组,又派生了颖体长大的大颖组和长颖组。  相似文献   

14.
Cytotaxonomically investigated in this work were 6 species in 4 genera of Polygonateae (sensu Krause, 1930). Each species was karyotypically analysed using 5 somatic metaphase cells with well-spread chromosomes. The chromosome classification follows Levan et al. (1964) and the karyotype classification is according to Stebbins (1971). The materials used are listed in the Appendix and the vouchers are deposited in PE. The chromosome numbers and karyotypes of Disporum megalanthum and Disporopsis aspera are reported here for the first time, and those of Chinese Maianthemum bifolium are also reported for the first time. The results are shown as follows. (1) Disporum Salisb. D. megalanthum Wang et Tang from tthe Wolong Nature Reserve, Sichuan, is found to have a karyotype 2n=16=2m(1SAT)+6sm(1SAT)+8st (3SAT) (Plate I, A). The parameters of chromosomes are listed in Table 1 and the idiogram is shown in Fig. 1, A. The chromosomes range in length from 8.5 to 29.3 μm, with the ratio of the longest to the shortest 3.45. The karyotype belongs to Stebbins' (1971) 3B. In a somatic chromosome complement the 2nd, 4th, 6th and 7th pairs each have one chromosome carrying a satellite, showing heterozygosity. Another material from the Qinling Range, Shaanxi, is shown to have 2n=16=2m(1SAT) +8sm(3SAT)+6st (Plate 1, B). The parameters of chromosomes are listed in Table 1 and the idiogram is presented in Fig. 1, B. The chromosomes range in length from 6.3 to 22.6μm, with the ratio of the longest to the shortest 3.61, and thus the karyotype belongs to 3B. The karyotype shows clear heterozygosity (Fig. 1, B). The two chromosomes of the first pair have arm ratios 2.38 and 1.82 respectively, but they are equal in length, 22.6 μm. It seems to us that a pericentric inversion has taken place in one of the two chromosomes. Moreover, the 3rd and 4th pairs each have one chromosome carrying a satellite attached to the long arm. These two materials are of the basically same karyotype, the major difference between them being that the 3rd pair in the former consists of two st chromosomes with the arm ratio 3.15, while the corresponding pair in the other is of two m chromosomes with an arm ratio 1.67. Seven East-Asian species of the genus Disporum are reported to have 2n=14, 16 and 18 (or 16+2B?), but 2n=16 is common to all the species, and therefore the basic number of the group is x=8. For the North American group of the genus, however, 3 species (D. hookeri, D. lanuginosum, D. oreganum) are of 2n=18, D. smithii is of 2n=16, and D. maculatum 2n=12. Chromosome numbers are more variable in the North American group, but x=9 seems to be a dominant basic number. Even more striking difference in karyotype between the two groups exists in size of chromosomes, 2.0-4.9μm.for the North American group, while 4.016.0 μm for the East-Asian counterpart (Therman, 1956) (Our result shows 6.3-22.6 μm and 8.5-29.3 μm for the two materials). This remarkable contrast in karyotype is clearly correlated with the differentiation in gross morphology. The East-Asian species have calcarate tepals but no reticulate veins of leaves, whereas the North American ones have reticulate veins but spurless tepals. The evidence from karyotype and morphology seems to justify the restoration of the genus Prosartes for the Nortth American species (Conover, 1983, cf. Dahlgren et al. 1985). (2) Disporopsis Hance D. pernyi (Hua) Diels from Mapien, Sichuan, is of 2n = 40 = 23m(2SAT)+13sm(2SAT) + 2st+ 2t(2SAT) (Plate 1, C). The parame- ters of chromosomes are listed in Table 2, and the idiogram is shown in Fig. 2, A. The chromosomes range in length 5.2-16.2μm, with the ratio of the longest to the shortest 3.11, and thus the karyotype belongs to 2B. D. aspera (Hua) Engl. ex Krause also from Mapien, Sichuan, is found to have 2n=40=30m+8sm(2SAT)+2t(2SAT) (Plate 1,D). The parameters of chromosomes are listed in Table 2, and the idiogram is shown in Fig. 2, B. The chromosomes range in length 5.2-14.7 μm, with the ratio of the longest to the shortest 2.84. Therefore, the karyotype belongs to 2B. Another material from the same locality but different population was also examined and found to have 2n=40=30m+6sm+2st(2SAT) (Fig. 2, C). D. arisanensis (=D. pernyi) from Taiwan is reported to have 2n=40=26m+12sm+2st (Chang and Hsu, 1974), D. fusco-picta from the Philippines 2n=40=22m+16sm+2st(2SAT) (Kumar and Brandham, 1974), and D. longifolia from Thailand 2n=40 (Larsen, 1963). Thus, the species in the genus, except the newly described D. jingfushanensis Z. Y. Liu (1987) with no chromosome data, are all of 2n = 40, and the basic number of the genus is x = 20. From the karyotype formulae, asymmetry of the karyotypes increases from D. aspera to D. fusco-picta through D. pernyi, which may be correlated with the increasing specialization of gross morphology. (3) Maianthemum Web. M. bifolium (L.) F. W. Schmidt from the Qinling Range, Shaanxi, is found to have 2n = 36 = 20m + 10sm + 4st + 2t (2SAT) (Plate 1, H). The parameters of the chromosomes are listed in Table 3, and the idiogram is shown in Fig. 3, D. The chromosome lengths range 2.4-8.2μm, with the ratio of the longest to the shortest 3.43. The karyotype thus belongs to 2B, and is slightly bimodal: the first 10 pairs and the pair of sat chromosomes are larger than the rest 7 pairs, the ratio of the shortest in the former group to the longest in the latter group being 1.24. (4) Polygonatum Mill. P. humile Fisch. ex Maxim. from Chicheng County, Hebei, is shown to have a karyotype 2n= 20= 10m(2SAT)+6sm(2SAT)+ 4st (Plate 1, G). The parameters of chromosomes are listed in Table 4, and the haploid idiogram is shown in Fig. 3, C. The chromosome lengths range from 3.0 to 10.0μm with the ratio of the longest to the shortest 3.3. The karyotype therefore belongs to 2B. P. odoratum (Mill.) Druce Two materials in this species were examined. One from Chicheng County, Hebei, has 2n=20=10m+10sm(3SAT) (Plate 1, E). The parameters of chromosomes are presented in Table 4 and the somatic idiogram in Fig. 3, A. The chromosomes range in length 3.1-8.8 μm, with the ratio of the longest to the shortest 2.8. The karyotype is thus of 2B. The other from the Qinling Range, Shaanxi, is found to have 2n=20= 12m(4SAT)+8sm(2SAT) (Plate 1, F). The parameters of chromosomes are listed in Table 4, and the haploid idiogram is shown in Fig. 3, B. The chromosomes range in length 4.2-10.9 μm, with the ratio of the longest to the shortest 2.6. The karyotype is also of 2B. P. odoratum is widely distributed in Eurasian temperate region and its cytological reports are frequently seen. All the materials outside of China, from Portugal to Japan, are reported to have 2n=20, except one material from east Sayan in SE Siberia, which is reported to have 2n=30 (Krogulevich, 1978). In China, however, three chromosome numbers have so far been reported under the name P. odoratum, 2n=20 from the Changbai Mountains, Jilin Province (Fang, 1989), Qinlong County, Hebei Province (Wang et al. 1987), the Jinfo Mountains, Sichuan Province (in cultivation), besides the two materials used in this work; 2n=22 from Mt. Jinshan in Beijing (Li, 1980), Wuhan in Hubei Province, Yixin in Jiangsu Province and Mt. Emei in Sichuan Province (Fang, 1989); 2n=18 from Yixin in Jiangsu Province and the Dabien Mountains in Anhui Province (Fang, 1989). It is, therefore, rather evident that the species under discussion is variable in chromosome number only in the southern part of its distribution area. Karyotypical morphology is also variable in this species. The 2n=20 group is found to have following karyotypes: 12m(4SAT)+8sm (in Austria, Hong et al. unpubl.), 14m+6sm (Jilin): 12m+8sm (Qinlong, Hebei): 10m+10sm (3SAT) (Chicheng, Hebei): 12m(4SAT)+ 8sm(2SAT) (Shaanxi) and 10m+6sm+4st(Mt. Jinfo, Sichuan). For the 2n=18 group, 10m+ 8sm (Anhui) and 8m+10sm (Jiangsu) have been found. In the 2n=22 group these karyotype formulae so far reported are all 10m+8sm+4st. Comparing the karyotypes in the three groups we find that 4st chromosomes are always present in the 2n=22 group, while in the other two groups, except the karyotype 10m+6sm+4st found from the Jinfo Mountains in Sichuan, all the karyotypes consist of m and sm chromosomes. Based on the correlation between karyotypical data and cryptic morphological differences Wang et al. (1988) consider Polygonatum odoratum as a complex, which consists of three species: Polygonatum odoratum (s. str. 2n=20), P. macropodium Turcz. (2n=22) and P. simi-zui Kitag. (2n=18). But in this complex biosystematic problems, such as relationship between chromosome number and chromosome structure, evolutionary relationship of the different chromosome numbers, relationship between means of reproduction (extent of vegetative propagation) and karyotype variation are still unresolved and deserve further studies. Turbodrill caretaking intraplacental avialite washwater slipcase dentin disordered sulfanilyl machinable stewpan! Netherward pressbodies horror abscissa, keratosis frieze. 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Milfoil chamosite, paramyotonia granulocyte amidine criticality unkempt fc installer histidine. Decorative.   相似文献   

15.
The present paper deals for the first time with an analysis of the karyotypes of Athrotaxis cupressoides Don and A. selaginoides Don endemic to Tasmania (Australia). Their morphology of somatic chromosomes in seed root-tip cells, chromosome measurements, and diagrams are shown in Plate 1, Table 1 and Fig. 1 respectively, The karyotypic formulas of the two species are 2n = 22 = 22m (2SAT) and 2n = 22 = 20m(2SAT ) + 2sm according to of terminology Lexvan et al (1964). They all belong to IB type of Stebbins’(1971)karyotypic asymmetry which was reported for the first time in the higher plants by Li(1987b). Their chromosome complements are 22 = 2L + 10M2+ 8M1+ 2S and 22 =2L+ 10M2+ 6M1+ 4S respectively according to the standard defined by Kuo et al. (1972) based on relative length. The karyotype of A. selaginoides is more advanced than that of A. cupressoides. In the light of karyotypic data, the sequence of the taxo-diaceous genera (excl. Sciadopitys) from primitive to advanced may be in the following order: Cryptomeria, Glyptostrobus, Taxodium, Metasequoia, Sequoiadendron, Sequoia, Athrotaxis, Cunninghamia and Taiwania. The genus Athrotaxis is closely related to Sequoia (Sequoiadendron) and Cunninghamia The peculiarity of the karyotype of Athrotaxis deserves the establishment of a new status Arthrotaxoideae (Wettstein) L. C. Li This suggestion is also supported by the data from morphology, embryology, palynology and geography. The family Taxodiaceae is divided into six subfamilies and nine genera, as shown in the following table:————————————————————————————————————————————————— 1. Cryptomerioideae Hida Cryptomeria D. Don 4. Arthrotaxoideae (Wettstein) L. C. Li 2. Taxodioideae Pilger Glyptostrobus Endl. Taxodim Richard Athrotaxis D. Don 3. Sequoideae Saxton metasequoia Miki ex Hu et 5. Cunninghamioideae Hida Cunninghamia Cheng Sequoiadebron Buch. Sequoia Endl. R.Brown 6. Taiwanioideae (Hayata)L. C. Li Taiwanta Hayata————————————————————————————————————————————————— The systematic positions of Athrotaxis in the systems of other authors are dis-cussed too.  相似文献   

16.
4种(变种)辣椒的核型研究   总被引:5,自引:0,他引:5  
李光涛  梁涛   《广西植物》1993,13(2):155-158
本文研究了辣椒属4种(变种)的核型,各个种的核型可简式为小米辣2n=24=23m+1sm:簇生辣2n=24=20m+2sm+2st:樱桃辣2n=24=20m+4sm(2SAT):“印度辣”2n=24=22m+2st。按照Stebbins的核型分类,小米辣为2A型;簇生辣和樱桃辣为2A型,印度辣为2B型。  相似文献   

17.
This paper reports chromosome numbers and karyotypes of five species of the genus Fritillaria from south Anhui. The origin of the material used in this work is provided in Table 1, micrographs of mitotic metaphase in Plate 1,2, and the parameters of chromosomes in Table 2. Except F. thunbergii Miq., the karyotypes and chromosome numbers of all the species in this paper were studied for the first time. The results are shown as follows: 1. Fritillaria qimenensis D. C. Zhang et J. Z. Shao Collected from Qimen, Anhui, it has the karyotype formula 2n = 24+4Bs = 3m+lsm+8st (2sc)+12t (2sc)+4Bs (Plate 1:1, 2). The chromosomes range in length 8.72-19.13μm, with the ratio of the longest to the shortest 2.19. Therefore, the karyotype belongs to Stebbins’ (1971) 3B. The secondary constrictions are found on the long arms of 7th and 10th pairs. All the five B-chromosomes are of terminal centromeres. The two chromosomes of the second pair show heteromorphy (Fig. 1, E) with arm ratios 1.86 and 1.56 respectively. 2. Fritillaria monantha Miq. var. tonglingensis S. C. Chen et S. F. Yin Collected from Tongling, Anhui, this species is shown to have three chromosome numbers, 2n =24+5Bs, 2n=24+2Bs and 2n=24. This paper reports 2 cytotypes: Type I: 2n = 24+5Bs = 4m+8st (2sc) +12t (2sc) +5Bs (Plate 1: 3, 4). The chromosomes range in length from 10.40 to 22.19μm, with the ratio of the longest to the shortest 2.13. It belongs to 3B of stebbins’(1971) karyotypic symmetry. The secondary constrictions are found on the short arms of 7th and the long arms of 9th chromosome pairs. The metacentric B-chromosomes and the small satellites located on the short arms are major characters of this cytotype. Type II: 2n=24=2m+2sm+8st(2sc)+12t(2sc) (Plate 1:5, 6). The chromosomes range in length from 13.84 to 29.81μm, with the ratio of the longest to the shortest 2.15. The karyotype belongs to Stebbins’3B. The secondary constrictions are found on the long arms of 5th and 10th pairs. No B-chromosomes are found. 3. Fritillaria xiaobeimu Y. K. Yang, J. Z. Shao et M. M. Fang Collected from Ningguo, Anhui, it has karyotype formula 2n = 24 = 2m+2sm+10st (4sc) + 10t (Plate 2:7, 8). The chromosomes range in length from 13.86 to 26.27μm, with the ratio of the longest to the shortest 1.89. The karyotype belongs to stebbins’3A. The secondary constrictions are found on the long arms of 7th and 9th pairs. 4. Fritillaria ningguoensis S. C. Chen et S. F. Yin Collected from Ningguo, Anhui, it is of karyotype formula 2n = 24 = 2m+2sm+8st (2sc) +12t (Plate 2: 9, 10). The chromosomes range in length from 9.11 to 23.23μm, with the ratio of the longest to the shortest 2.55. The karyotype belongs to Stebbins’3B. The secondary constrictions are only found on the long arms of the 10 th pair. 5. Fritillaria thunbergii Miq. Collected from Ningguo, Anhui, it is of karyotype formula 2n = 24 = 2m+2sm+8st(2sc) +12t(2sc)(Plate 2:11, 12). The chromosomes range in length from 8.83 to 19.85μm, with the ratio of the longest to the shortest 2.25. The karyotype belongs to stebbins’3B. There are secondary constrictions on the long arms of 5th and 7th pairs. The karyotype of the Ningguo material is similar to that of the Huoqiu (Anhui) material reported by Xu Jin-lin et al. (1987), but it is obviously different from 2n=2m(sc)+2sm+4st(2sc)+16t (2sc) reported byZhai et al. (1985) for the material from Xingjiang, Northwest China.  相似文献   

18.
In the present paper the karyotypes of Smilacina tatsienensis (Franch.) Wang et Tang and Ophiopogon japonicus (L. f.) Ker.- Gawl. in Sichuan were analysed. The karyotypes of the two species are reported for the first time. The results are shown as follows. Smilacina tatsienensis (Franch.) Wang et Tang is a dipoiid. Its karyotype formula is 2n=2x=36=16m+10sm+10st(4SAT) (Plate 1: Fig. 1, 3). The karyotype is bimodal with ten large and eight small chromosome pairs and the length ratio of the tenth pair to the eleventh being 1.33. The length ratio of the largest chromosome and the smallest one is 4.33. Ophiopogon japonicus (L.f.) Ker.-Gawl. is a mixoploid, with diploid, triploid and tetraploid cells in a single plant. The karyotype formula of the diploid is 2n=2x=36=18m (4SAT)+18sm(Plate 1: Fig. 2, 4). The species is of a bimodal karyotype with eight large and ten small chromosome pairs and the length ratio to the eighth pair and the ninth being 1.10.There are nine metacentric pairs (two pairs of sat-chromosomes) and nine submetacentric pairs.  相似文献   

19.
仙茅属三个国产种的核型研究   总被引:1,自引:0,他引:1  
本文报道了中国产三种仙茅植物的核型。1.绒叶仙茅Curculigo crassifolia (Baker) Hook. f., 2n=2x=18=10m(4SAT) 8 sm;2.大叶仙茅C.capitulata(Lour.)O. Kuntze,2n=2x=18=10(2SAT) 8sm;3.中华仙茅C.sinensis S.C.Chen,2n=2x=18=8m(3SAT) 10sm(2SAT)。其中中华仙茅的核型为首次报道。虽然三种仙茅的核型都是“2B”型,但中华仙茅的核型不对称性比绒叶仙茅和大叶仙茅强。  相似文献   

20.
对澳大利亚特产的Callitris属植物C.preissii,C.verrucosa,C.endlicheri(柏科)的核型进行了分析,后2种的为首次报道。它们的核型公式分别为K(2n)=22=22m(2SAT),22m(2SAT)和22m(6SAT),均属1A核型类型。染色体相对长度组成同是2n=22=10M_2+12M_1该3种及其他8种Calltris属植物一致的核型K(2n)=22m和1A类型的通常被认为是最对称和原始的。因此该属在柏科的系统发育上也许处于相当原始的地位。  相似文献   

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