Decaploidy in Fragaria iturupensis (Rosaceae)

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.     

Karyotype Analysis of Eight Species of Polygonatum Mill.

Meiosis and mitosis of eight species of Polygonatum from Sichuan, China, were investigated. Ten bivalents (n=10) at meiosis of pollen mother cells were observed ih P. odoratum (Mill.) Druce. Meiotic observation on pollen mother cells in P. punctatum Royle ex Kunth shows 16 bivalents (n=16) at diakinesis, P. kingianum Coll. et Hemsl. 13 bivalents (n=13) at diakinesis. P. zanlanscianense Pamp. 15 bivalents (n=15) in MI, P. cirrhifolium (Wall.) Royle 28 bivalents at diakinesis. Somatic chromosomes were observed in root tip cells. The karyotype formulae are as follows: P. odoratum (Mill.) Druce K(2n)=20=4st+6sm+10m; P. cyrtonema Hua K(2n)=20=6sm+14m; P. punctatum Royle ex Kunth K(2n)=32=2t+8st+ 2sm+20m; P. kingianum Coll. et Hemsl. K(2n)=26=8st(2SAT)+14sm+4m; P. alternicirrhosum Hand.-Mzt. K(2n)=32=6st+8sm+18m(2SAT); P. zanlanscianense Pamp. K(2n)=30= 2t+6st+6sm+16m(2SAT); P. sibiricum Delar. ex Redouté K(2n)=24=2t+14st(2SAT)+6sm +2m; P. cirrhifolium (Wall.) Royle K(2n)=56=18st+10sm+28m. The karyotypes of P. punctatum, P. kingianum, P. alternicirrhosum and P. cirrhifolium are reported for the first time. Both the chromosome number and structure in our materials are certainly different from thoses in previous reports. Of numerical variation polyploidy and aneuploidy have been recorded, and aneuploidy is frequent. According to degree of asymmetry of the karyotype, the 8 species are divided into three types: 2B, 3B, 2C. The increasing asymmetry is correlated with the increasing of the chromosome number. There are no obvious differences in chromosome number and karyotype between Alternifolia Baker and Verticillate Baker. They are not two natural groups. This opinion is different from that of Therman and Suomalainen.     

中国西北地区11种黄耆属植物的细胞学研究

对分布于中国西北地区的11种黄耆属植物进行了细胞学研究,其中9种作了核型分析。结果表明,杯萼黄耆（Astragalus cupulicalycinus）为六倍体（2n=48）,酒泉黄耆（A.jiuquanensis）具有2种细胞型：2n=32的四倍体和2n=48的六倍体,其余种类均为二倍体（2n=16)。9个种的核型公式分别为：木黄耆（A.arbuscula）,2n=16=14 2sm,“1A”核型;胀萼黄耆（A.ellipsoideus）,2n=16=10m 6sm,“2A”核型;粗毛黄耆（A.scabrisetus),2n=16=14m 2sm,“1A”核型;秦岭黄耆（A.henryi),2n=16=8m 8sm(2SAT),“2A”核型;哈巴河黄耆（A.habaheensis）,2n=16=10m 6sm(2SAT),“2A”核型;变异黄耆（A.variabilis）,2n=16=4m 10sm(2SAT) 2t,“2A”核型;喜沙黄耆（A.ammodytes),2n=16=6m 10sm(2SAT),“2A”核型;密花黄耆（A.densiflorus),2n=16=6m(2SAT) 10sm,“2A”核型;茧荚黄耆（A.lehmannianus),2n=16=14m(2SAT) 2st,“2A”核型。所有研究种中,仅变异黄耆的染色体数目有过报道,其余种的染色体数目及核型均为首次报道。     

国产姜科植物的染色体计数(5)

<正> 本文继续对7属15种国产姜科植物作染色体计数观察,其中10种是染色体计数的新纪录(表、图)。通过对黄花大苞姜(Caulokaempferia coenobialis)和大苞姜(C.yunnanensis)以及凹唇姜(Bosenbevgia rotunda)和心叶凹唇姜(B.fallax)的染色体观察,确定了大苞姜属(Caulokaempferia)和凹唇姜属(Bosenbergia)的染色体基数分别为12和9。     

青藏高原一些种子植物的核型研究

本文对产于青藏高原地区的１１个属１２个种植物进行了核型分析。大部份种为首次报道。它们的核型公式和核型不对称性如下：云雾雀儿豆Ｃｈｅｓｎｅｙａ ｎｕｂｉｇｅｎａ（Ｄ．Ｄｏｎ）Ａｌｉ,为２ｎ＝１６＝１０ｍ＋６ｓｍ,属２Ｂ型;变色锦鸡儿Ｃａｒａｇａｎａ ｖｅｒｓｉｃｏｌｏｒ Ｂｅｎｔｈ．,为２ｎ＝１８＝１４ｍ＋４ｓｍ,２Ｂ型;异叶青兰Ｄｒａｃｏｃｅｐｈａｌｕｍ ｈｅｔｅｒｏｐｈｙｌｌｕｍ Ｂｅｎｔｈ．,     

中国4种蝙蝠的G-带和C-带

首次报道了中国4种蝙蝠的G-带和C-带核型。大长舌果蝠(Eonycteris spelaea)二倍染色体数目(2n)为36,常染色体臂数(FN)为56;马来假吸血蝠(Megaderma spasma)2n=38,FN=70;黑髯墓蝠(Taphozous melanopogon)2n=42,FN=64;皱唇蝠(Chaerephon plicata)2n=48,FN=54。通过C-带显示,除着丝粒异染色质外,在皱唇蝠的许多染色体臂内和马来假吸血蝠染色体的端粒处也有较多的插入异染色质,大长舌果蝠的基因组中既有臂内异染色质也有端粒异染色质。     

宜昌百合根尖染色体C-带分析

利用Giemsa C-带方法对宜昌百合（Lilium leucanthum(Baker) Baker）进行研究。结果表明：宜昌百合（L. leucanthum）的染色体数目为2n＝2x=24,单套染色体的条带总数目为21条。其带型公式为：2n＝24＝6C+2CI+2I+2CI⁺+2CI⁺+4I⁺+2I⁺+2T⁺+2I+S。宜昌百合（L. leucanthum）每条染色体上都显示出显著的特征带,且带纹的深浅差异明显。宜昌百合（L. leucanthum）的强带主要集中在着丝点及附近区域。通过Giemsa C-带方法可以将宜昌百合（L. leucanthum）的每条染色体区分开。     

Cytological studies on six cyprinid fishes

The chromosome complements of six cyprinid fishes were studied, using the routine air-drying Giemsa staining technique. The diploid chromosome number recorded is 2n = 50 (8m+18sm+14st+10t) with NF = 90 in Aspidoparia morar, 2n = 50 (8m+12sm+12st+18t) with NF = 82 in Crossocheilus latius latius, 2n = 50 (6m+12sm–16st+16t) with NF = 90 in Labeo pangusia, 2n = 70 (16m+6sm+16st–32t) with NF = 108 in Perilampus atpar, 2n = 48 (4m+6st+38t) with NF = 58 in Puntius chrysopterus and 2n = 50 (2m+2sm+4st+42t) with NF = 58 in P. tetrarupagus. Sex chromosomes are not identifiable in any of these species. A pair of marker chromosomes has been observed in all species excepting A. morar.     

7种铁线莲的染色体研究

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。     

Cytogenetical studies in five Atlantic Anguilliformes fishes

The order Anguilliformes comprises 15 families, 141 genera and 791 fish species. Eight families had at least one karyotyped species, with a prevalence of 2n = 38 chromosomes and high fundamental numbers (FN). The only exception to this pattern is the family Muraenidae, in which the eight species analyzed presented 2n = 42 chromosomes. Despite of the large number of Anguilliformes species, karyotypic reports are available for only a few representatives. In the present work, a species of Ophichthidae, Myrichthys ocellatus (2n = 38; 8m+14sm+10st+6a; FN = 70) and four species of Muraenidae, Enchelycore nigricans (2n = 42; 6m+8sm+12st+16a; FN = 68), Gymnothorax miliaris (2n = 42; 14m+18sm+10st; FN = 84), G. vicinus (2n = 42; 8m+6sm+28a; FN = 56) and Muraena pavonina (2n = 42; 6m+4sm+32a; FN = 52), collected along the Northeastern coast of Brazil and around the St Peter and St Paul Archipelago were analyzed. Typical large metacentric chromosomes were observed in all species. Conspicuous polymorphic heterochromatic regions were observed at the centromeres of most chromosomes and at single ribosomal sites. The data obtained for Ophichthidae corroborate the hypothesis of a karyotypic diversification mainly due to pericentric inversions and Robertsonian rearrangements, while the identification of constant chromosome numbers in Muraenidae (2n = 42) suggests a karyotype diversification through pericentric inversions and heterochromatin processes.     

Cytology of ten species in Anemone,one in Anemoclema and six in Clematis (Trib. Anemoneae,Ranunculaceae) from China

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.     

锦鸡儿属植物4个种的核型分析

对4种锦鸡儿属(CaraganaFabr.)植物的核型进行了分析,得出4种染色体核型:秦晋锦鸡儿(C.purdom iiRehd.)染色体数为2n=16,其核型公式为2n=16=16 m(4 SAT);小叶锦鸡儿(C.m icrophyllaLam.)染色体数为2n=16,其核型公式为2n=16=14 m(2 SAT) 2 M;中间锦鸡儿(C.interm ediaKuang et H.C.Fu)染色体数为2n=18,其核型公式为2n=18=16 m(4 SAT) 2 M;树锦鸡儿(C.arborescensLam.)染色体数为2n=20,其核型公式为2n=20=20 m(4 SAT)。由此可推测:中间锦鸡儿可能为小叶锦鸡儿和树锦鸡儿或秦晋锦鸡儿和树锦鸡儿的中间类型或杂交种,也可能是具有递增染色体基数的不同种。     

蜘蛛抱蛋属的细胞分类学研究Ⅱ

文章报道了13种蜘蛛抱蛋属植物的染色体核型,并对属内核型进化规律作了总结。作者认为随体染色体和第1对染色体可以作为本属核型的特征染色体。染色体数目变异与花部式样密切相关。本属植物原始的染色体基数为x=19。此外,对非整倍性变异的主要机制也进行了讨论。     

版纳鱼螈和双带鱼螈核型的比较研究

本文对版纳鱼螈的核型作了观察,并与双带鱼螈进行了比较。两者的核型基本一致,均为2n=42,但版纳鱼螈的NF=62,而双带鱼螈的NF=60;版纳鱼螈的染色体有中部着丝粒、亚中部着丝粒和端部着丝粒三种类型,而双带鱼螈则无亚中部着丝粒的染色体。     

The chromosomes of Cepaea vindobonensis (Pulmonata: Helicidae) and the relationship between this species and the rest of the genus

The karyotype of Cepaea vindobonensis (Pfeiffer) (2 n = 50) is defined and compared with those of C. sylvatica (Draparnaud), C. nemoralis (L.) and C. hortensis (Müller). Cepaea vindobonesis shares its chromosome number with C. sylvatica. The genus Cepaea thus consists of two pairs of species, one with 2 n = 50 the other with 2 n = 44. The karyotype of C. vindobonensis is distinct from that of C. sylvatica as it lacks any discontinuity in its range of chromosome length and has all three of its longest chromosome pairs nearly identical. The two 2 n = 50 species both have an unusual meiotic bivalent showing a 'satellite-type' structure. It is apparent that the 2 n = 50 species are more closely related to each other than to the 2 n = 44 species. No precise definition of the evolutionary history can be given but a working hypothesis is suggested.     

Chromosome cytology,leaf epidermal morphology and palynology of Curcuma rubrobracteata (Zingiberaceae)

Chromosome cytology, leaf epidermal morphology and palynology of Curcuma rubrobracteata (Zingiberaceae), a species recently recorded from southern Yunnan, China, have been investigated. The somatic chromosome number is determined as 2n=9x=63, contrary to a previous count of 2n=6x=42 based on material from northeastern India. The upper epidermis is unicellular, non‐glandular, hairy along raised veins, with the epidermal cells being rectangular or polygonal in shape. The lower epidermis is glabrous, with the epidermal cells being circular or polygonal in shape, and smaller than the upper epidermal cells. The pollen grains are spherical or subspherical, non‐aperturate, with a nearly smooth exine, nanoverrucate and with an annular ridge.     

天南星科岩芋属的细胞地理学研究

本文报道了岩芋属三个种的染色体数目和核型:岩芋Remusatia vivipara是三倍体,核型公式为K(2n)=3X=42=42m;早花岩芋R. hookeriana为二倍体,核型公式为K(2n)=2X=28=22m(6SAT) 6m(2SAT);秀丽岩芋R. ornala,也是三倍体,核型公式为K(2n)=3X=42=36m(3SAT) 3sm 3st。在岩芋属中,岩芋是一个比较原始的种,秀丽岩芋较进化。岩芋属是热带非洲和热带亚洲间断分布的小属,它的原始类群岩芋(R. vivipara)的原始居群(二倍体居群)分布在印度南部,因而作者没想,古南大陆是岩芋属的起源地,本属向热带亚洲的扩散是与第三纪时喜马拉雅造山运动相联系的。     

国产毛茛科银莲花族十七种植物的细胞学研究

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。     

Biosystematic Observation on 5 Species of Consolida (Rannnculaceae)

The karyotypes of five species of the germs Consolida from SE Europe, Turkey and Iran (see Appendix Ⅰ for the detail information concerning the vouchers) were studied with 0.05% colchicin pretreatment followed by Carney Ⅰ fixation and Fenlgen squashing. The result shows that C. regalis ssp. regalis has a karyotype of 2n=16= 1(L)m- (SAT)+ 3(L)m + 6(S)st + 5(S)t+1(S)t(SAT)(Fig. 1A and Plate Ⅰ, G) and ssp. paniculata has a karyotype of 2n = 16 = 2(L)m (SAT) + 2(L)m + 6(S)st + 6(S)t (Plate Ⅱ,A) and 8 bivalents in meiosis (Piate Ⅱ, E, F); C. persica 2n = 14 = 2 (L)m (SAT) + 2(L)m + 3(S) st + 7(S) t(Plate Ⅲ, B; Fig. 1,B); C. stenocarpa 2n =16 = 2(L)m(SAT) + 2(L)m + 1(S)st + 11(S)t (Plate Ⅰ, C, Fig. 1, C); C, teheranica (see Appendix Ⅰ for the nomenclature) 2n = 16 = 4(L)m(SAT) + 2(S) st + 10(S) t (Plate Ⅲ, D; Fig. 1, D); C. scleroclada var. rigida 2n = 18 = 2(L)m (SAT) + 2(S)st + 14(S)t(Plate Ⅱ H, Ⅰ; Fig. 1, E) All the karyotypes here descr- ibed are highly asymmetrical and bimodal, and belong to the type 3C in the karyotype classification system established by Stebbins[14,15]. 2n=18 for the last mentioned taxon has been confirmed by the ,standard microtome sectioning method. Its meiosis was also examined with acetoorcein staining, and 9 bivalents were always found at MI, no meiotic aberrations being Observed. x=7 and x=9 are two new basic numbers even for the whole tribe of Delphineae. It is considered that the karyotype of 2n=18 is derived from that of 2n=16 by centic fission (Robertsonian exchange), while the karyotype of 2n=14 is derived from that of 2n=16 probably by successive unequal interchanges. As shown to Fig. 1 and 2. the complement of C. sclerocleda var. rigida (2n=18) has only one pair of large and metacentric chromosomes instead of 2 pairs of such chromosomes in the other species, but it has 2 extra pairs of small and terminal chromosomes as compared with the species with 2n=16. The complement in the taxon has, therefore, exactly the same fundamental number of chromosome arms as that of the other species with 2n=16 (for example, of C. stenocarpon), but it has two more centromeres. There are at least 2 pairs of chro- mosomes in the complement (3 and 5) which may be telocentric, i.e. T chromosomes in the sense of Levan et al[8] The small dots at the ends of the chromosomes may be the chromomeres in centric regions rather than short arms (Jones[6]). As the plants constantly show 9 bivalents .at the first meiotic division and have very high pollen fertility (98%) as well as good seed-set, the karyotype seems to be a stable one. Therefore, Consolida scleroclada var. rigida may have provided another example of spontaneous centric fission which has resulted in homozygous and stable telocentrics. John and Freemanm have argued for the mechanism of chromosomal structural variation based on the observed facts both in animals and plants. The cytogenetic model for the variation was formulated by Lima-de-Faria as early as in 1956 and revised by Jones[6], and the mo- lecular model for the mechanism recently by Holmquist et al.[4] As in the genus Delphinium, most species of Consolida are pollinated by long-tongued bumble-bees. In C. regalis (incl. both subspecies), C. stenocarpa and C. scleroclada var. rigida the isolated flowers (3–15 for each species) gave no any seeds. The flowers first emasculated and isolated and then pollinated with pollen collected from the same individuals in these three species (10–25 flowers for each species), however, all gave full seed-set. The experiment clearly shows that these three species, though self-com- patible, are obligately out-pollinated. It was Observed that the three species are pro- tandrous. When stigmata become 2-lobed and show their receptive surface, all the stamens have recurved down or laterally, forming a semi-circle, but the styles remain erect. Therefore the receptive stigmata are over 3 mm (C. regalis) or 5 mm (C. stenocarpa and C. scloroclada var. rigida) away from and above the anthers of the same flower Plate I, B, D and F). Self-pollination is thus prevented. Just-opened flowers, however, have always some stamens erect and with their dehiscing anthers correspondent in position to 2-lobed and receptive stigmata of other flowers (compare A with B, C with D, E with F in Plate II). Pollen grains are therefore easily taken by a bumble-bee from dehiscing anthers onto receptive stigmata. Here we see a perfect mechanism which prevents self-pollination and secure out-pollination. It was observed during the experiment that a bumble-bee, Bombus agrorum F., only visited the straight-spurred species, C. regalis (both subspecies), but never visited the curved-spurred species, C. scleroclada var. rigida and C. stenocarpa. Another bumble-bee, B. hortorum L., however, visited both the straight-spurrod and curved-spurred species, but when it visited C. stenocarpa it sometimes kept the body upside down. Consolida teheranica (Boiss.) Hong, on the contrary, is an inbreeder. Its stigmata and anthers become mature at the same time, and its styles and stamens always remain erect with the dehiscing anthers right over the receptive stigmata. It was also found that its corollae are not fully opened (Fig. 3). As expected, two isolated flowers gave 9 good seeds. The results of crossing experiment axe shown in Fig. 4. Only the cross between two subspecies of C. regalis resulted in an interfertile hybrid, which was vigorous, showed normal meiosis, had 94% pollen fertility, and gave good seed-set. The cross combination C. stenocarpa×C. scleroclada var. rigida gave some 50 % seed set, but the seeds yielded from the cross did not germinate though looked good. The other crosses gave no any seeds.     

Chromosomal behaviour and evolutionary trends in Chlorophytum (Liliaceae)

Chlorophytum laxum R. Rr. (Liliaceae) is a common perennial herb occurring in many parts of India, Ceylon, Borneo, Tropical Africa and Australia. The earlier cytological studies report two numbers of chromosomes, viz. 2n = 14 & 16, for the species. The present study, based on meiotic behaviour, concludes that this species is a segmental allopolyploid from two closely related but still unknown species with 2n = 8 chromosomes. Further evolution proceeded in two different directions. In one, diploidization by chromosomal rearrangements resulted into species with 2n = 16 chromosomes, while in the other, elimination of a non-homologous segment gave rise to species with 2n = 14 chromosomes and several autopolyploids.