A Chromosomal Study of Eight Species in Allium Sect. Rhiziridium G. Don in China

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.     

黄芪复合体（豆科）核型研究补充材料

本文首次报道了民和黄芪的染色体数目及核型。发现该种与黄芪复合体其它类群的染色体数目相同,但核型有别,其核型公式为２ｎ＝１６＝８ｍ（２ＳＡＴ）＋８ｓｍ。这种核型变异与它的形态变异一致。在黄芪复合体内,每一类群的染色体至少具１对随体,且附着在最后１对染色体的短臂上（除蒙古黄芪具２对随体外）,而Ｔｏｈ（１９７１）报道采自Ｋｙｕｎｇｉ和Ｍｔ．Ｈａｒｌａ膜荚黄芪和高山膜荚黄芪（新拟）的染色体不具随体,可能观察有误。     

Chromosome Studies of Subgenus Gymnaconitum Endemic to China and Beesia (Ranunculaceae)

The paper reports chromosomal number and chromosomal morphologies of annual Aconitum gymnandrum endemic to China and Beesia calthifolia for the first time. Of the two spcies, chromosome number is same (X=8, 2n=16) and chromosome average lengths are 6.17μ , 10.73μ respectively. The longest chromosome 1, the short chromosomes 3-5, 7 and the shortest chromosome 8 are metacentrical (m), the chromosomes 2, 6 are submetacentrical (sm), and the pairs 4, 5, 8 have satellites in the karyotype of A. gymnandrum. In B. calthifolia, all of the chromosome 1-5 are the long m, the chromosomes 6, 8 are the short sm and the 7 is telocentrical (t). The pairs 3, 4, 6 have satellites. According to the comparison of karyotypes of three subgenera—subgen. Paraconitum, subgen. Aconitum and subgen. Gymnaconitum in Aconitum, the evolution trend of chromosomes is further discussed. Finally, the relationship between Aconitum and Beesia is also discussed in thispaper.     

Report on Karyotypes of 10 Species of Liliaceae (s. l.) From Qinling Range

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.     

Karyotypes of the Genus Fritillaria from South Anhui

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.     

菊科栽培植物黄莺花的核型分析

研究了我国广东佛山栽培的菊科(Astcraccae)植物黄莺花(Solidago canadensis var.gilvocanescens Rydb.)的染色体数目和核型.其染色体数目为2n=18,带有一对随体,核型公式为2n=2x=18=14m+4sm(2SAT),核型类型为"2A"型.     

加拿大引进的二倍体燕麦种质的核型鉴定

采用常规压片法对砂燕麦、西班牙燕麦和短燕麦3个二倍体燕麦种进行了核型研究。结果表明:砂燕麦染色体核型公式为2n=2x=14=10m+4sm(2SAT),具近中部和中部着丝点染色体,第4对染色体组的短臂上有1对随体,核不对称系数为68.17%;西班牙燕麦染色体核型公式为2n=2x=14=10m+4sm(2SAT),具近中部和中部着丝点染色体,第7对染色体短臂上有1对随体,核不对称系数为59.31%;短燕麦染色体核型公式为2n=2x=14=6m+4sm+4st(2SAT),具近端部、近中部和中部着丝点染色体,第6对染色体组的短臂上有1对随体,核不对称系数为63.91%。虽然3个燕麦种的核型均为2A,但它们的染色体形态有明显不同,比较认为砂燕麦相对进化,短燕麦次之,西班牙燕麦较原始。本研究对燕麦种质资源的核型分析及进化地位研究具有参考价值。     

睡莲科的核型分析及其分类学位置的探讨

本文对睡莲科6属6种代表植物的核型进行了研究,并探讨了它的分类学位置。结果如下：莲2n＝16=9sm+4m+3st;王莲2n＝24=8sm+8m+8T,蓝睡莲2n＝28,可配成14对,染色体小,第l号染色体上有2条随体;萍蓬草2n＝34＝18m+16sm;芡实2n=58,可配成29对,染色体小,第l号染色体有2条随体,莼菜2n＝72,可配成36对,染色体按大小可分成大,中、小三个类别。除莲外,其它5种植物的核型为首次报道。莼菜的体细胞染色体数目2n＝72和国外报道的2n＝80不相一致。莲的染色体以及形态学特征和其它睡莲科分类群显著不同,可将其从睡莲科中独立出来,并成立莲科和莲目。原归属于睡莲科的分类群仍组成睡莲目,并分别置于莼菜科和睡莲科。     

A Comparative Karyotypic Study of Three Species in Fritillaria

The present paper deals with a comparative karyotypic study of three species in Fritillaria-F. thuncergii Miq., F. anhuiensis S. . Chen et S. F. Yin and F. hupehensis Hsiao et K. C. Hsia. The karyotype of F. anhuiensis S. C. Chen et S. F. Yin is first reported. The karyotypes of the three species of Fritillaria are rather similar, all with K(2n)=24= 2m+2sm+12t+4st+4m (SAT), showing a close interspecific relationship. They all have two pairs of st chromosomes, one of which is the third chromosome in all the three species studied, but the other is the seventh in F. thunbergii Miq, the eighth in F. anhuiensis S. C. Chen et S. F. Yin, and the fifth in F. hupehensis Hsiao et K. C. Hsia. It tells us that there are some differences in their karyotypes. All of the three species possess two pairs of satellite chromosomes with the satellites located on the long arms. A heterochromatic zone is found sometimes on long arms of No. IX chromosome in each species of Fritillaria and on one of No. I chromosomes in both F. thunbergii Miq. and F. anhuiensis S. C. Chen et S. F. Yin, a chromosome polymorphism occurring between populations of Fritillaria. In addition, three B chromosomes are always found in most root-tip cells of F. hupehensis Hsiao et K. C. Hsiao.     

中国特有的八角莲和六角莲的核型

本文研究了八角莲Dysosma versipellis(Hance)M.Cheng和六角莲Dysomapleiantha((Hance)Woodson的核型。二者的染色体数目均为2n=12,由四对具中部着丝点染色体、一对具近中部着丝点染色体和一对具端部着丝点染色体组成,各有一对染色体具有次缢痕,八角莲的次缢痕在第3对染色体的长臂上,六角莲的次缢痕在第1对染色体的短臂上。二者均属较对称的“2A”核型。但它们在染色体相对长度的变异幅度和差值、臂比的变异幅度和差值以及最长与最短染色体的比值上均有微小的差异。结果表明二者有密切的亲缘关系。演化趋势是八角莲→六角莲。八角莲的核型为首次报道。     

A Chromosomal Study on 7 Species of Smilax L.

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.     

慈姑45S rDNA和端粒序列检测及核型分析

以45S r DNA和拟南芥型端粒序列为探针对慈姑(Sagittaria trifolia L.)有丝分裂中期染色体进行单色和双色荧光原位杂交分析,并用银染方法检测慈姑45S r DNA位点的表达,最后结合染色体测量数据和45S r DNA杂交信号建立慈姑的核型。结果显示,慈姑的单倍基因组总长度为76.9±1.38μm,最长染色体为11.55±0.10μm,最短染色体为4.54±0.27μm;慈姑的核型公式为:2n=22=2m+2sm+14st+4t,核型不对称性参数CI、A1、A2、As K(%)、AI分别为19.86±11.06、0.72、0.27、78.82、15.29,核型属于Stebbins类型中的3B型。慈姑具有3对45S r DNA位点,分别位于第8、9、10号染色体的短臂末端。拟南芥型端粒序列的杂交信号出现在慈姑每一条染色体的长、短臂末端。银染检测到6个Ag-NOR和6个核仁,表明3对45S r DNA位点在间期核都有表达。本研究结果为药食兼用植物慈姑提供了分子细胞遗传学基础资料。     

Cytotaxonomical Studies on Liliaceae (s.l.): (2) Report on Chromosome Numbers and Karyotypes of 8 Species of 8 Genera from Zhejiang,China

Eight species in eight genera of Liliaceae from Zhejiang were cytotaxonomically studied in this work. The karyotypes of Chinese materials of these species are mostly reported for the first time. The results are shown as follows (see Table 2-4 for chromosome parameters of them): 1. Disporum sessile D. Don Sixteen chromosomes are counted at metaphase of roottip cells.The Karyotype formula is 2n=16=2lm+2sm+4st+2sm+3sm+ 1sm(SAT)+2st (Plate 1: 2-3, see Fig. 1:1 for its idiogram). The Karyotype belongs to 3B in Stebbins’ (1971) karyotype classification, and consists of four pairs of larger chromosomes (1-4) and four pairs of smaller chromosomes (5-8). One SAT-chromosome is situated at the sixth pair. The chromosomes range between 4.85-16.63μm. The karyotypic constitution is similar to that of Japanese material reported by Noguchi (1974). Chang and Hsu (1974) reported 2n=14=13st+1sm and 2n= 16=2m + 13st + 1sm for the material from Taiwan under the name of D. shimadai Hay. (=D. sessile D. Don). Compared with our result of D. sessile, the differences are obvious. 2. Polygonatum odoratum (Mill.) Druce PMCs diakinesis shows eleven bivalents, n = 11, 5 large and 6 small (Plate 2:5). The meiosis is normal. The majority of reports of this species are 2n=20, with a few 2n=22 and 30 (see Table 1). The materials from southen Siberia and the Far East in USSR are all of 2n= 20. Our result is the same as recorded by Jinno (1966) in the Japanese material and by Li (1980) from Beijing. Ge (1987) reported 2n=20 in the cultivated individuals of Shandong, China, showing that both 2n=20 and 22 exist in China. 3. Scilla scilloides (Lindl.) Druce This species has the somatic chromosome number 2n=18 (Plate 1: 4-6, see Fig. 1:2 for its idiogram), of which two groups of chromosomes can be recognized, i.e. the 1 st -5 th pairs of large and the 6 th-9th pairs of small chromosomes. A distinct character of the karyotype is that two satellites are attached to the short arms of the 1st pair of chromosomes. The degree of asymmetry is of 3C. The karyotype formula is 2n = 18 = 2sm (SAT) + 6st + 2t+ 6m + 2sm. The chromosomes range from 2.02 to 11.93 μm. The Previous counts on the species are 2n = 16, 18, 26, 34, 35, 36 and 43 (see Table 1). The present investigation confirms Noda’s and Haga’s results. The species is considered to be of two genomes, namely A(x = 8) and B(x = 9). Our result shows a genome composition of BB, having a pair of large SAT-chromosomes. Chang and Hsu (1974) reported 2n = 34 from a population of Taiwan, an amphidiploid (AABB), Karyotypes of other Chinese populations are worth further researches. 4. Tricyrtis macropoda Miq. The chromosome number of somatic cells is 2n= 26, and PMCs MII shows 13 bivalents (n= 13) (Plate 3:1-3, see Fig. 1:3 for its idiogram). The karyotype formula is 2n= 26= 6m + 10sm + 6st + 4st (or t), which is composed of chromosomes: 4L + 22S in size. The degree of asymmetry is of 3B. No centromeres of the 12th and 13th pairs of chromosomes were observed at metaphase, and the chromosomes may be of st or t. Nakamura (1968) reported 2n= 26(4L+ 22S)= 2sm+ 2sm-st+ 14st-sm+ 8st for T. macropoda Miq. and 2n= 26(4L+ 22S)= 8m+ 2sm+2sm-st+ 2st-sm+ 12st for its ssp. affinis, both from Japan. It is clear that the major character of their karyotypes, i. e. 4L + 22S, is consistent with that reported here. Based on the previous and present reports, all Tricyrtis species studied are remarkably uniform in the basic karyotype, i. e. 4L + 22S. 5. Allium macrostemon Bunge. The present observation on the root-tip cells of the species shows 2n = 32 (Plate 3: 4-5, see Fig. 1:4 for its idiogram). The karyotype formula is 2n (4x)= 32= 26m + 6sm, which belongs to 2B, being of high symmetry. Except the 6th, 10th and 13th pairs of chromosomes all the are metacentric. Chromosomes of this species are large, ranging from 5.94 to 18.06 μm. Our result agrees with Kawano’s (1975) report under the name of A. grayi Regel ( = A. macrostemon, Wang and Tang 1980). 6. Asparagus cochinchinensis (Lour.) Merr. Ten bivalents were observed in PMCs MI, n=10 (Plate 1: 1). The present result confirms the number of a population of Taiwan recorded by Hsu (1971). 7. Ophiopogon japonicus (L. f.) Ker-Gawl. The species from Mt. Taogui, Hangzhou, is found to have 2n (2x)=36=22m + 14sm (Plate 2: 1,5, see Fig. 1:5 for its idiogram) which belongs to 2B. The karyotype is composed of 2 medium-sized chromosomes with metacentric centromeres and 34 small chromosomes, ranging from 1.34 to 4.92 μm. The populations from Mt. Tianzhu and Mt. Yuling, Zhejiang, are found to be aneuploids at tetraploid level (2n=64-70). It is interesting that Nagamatsu (1971) found the karyotypes of Japanese materials to be 2n= 67 and 68, also showing unsteady 4x karyotypes of this species. In the previous. reports (see Table 1), the chromosome numbers of this species are mainly 2n = 72, besides 2n = 36 recorded by Sato (1942) from Japan. 8. Liriope platyphylla Wang et Tang The somatic complement of the species collected from Mt. Tianzhu, Hangzhou, is 2n = 36 (Plate 2: 3-4, see Fig. 1:6 for its idiogram). The karyotype is 2n(2x) = 36 = 16m + 20sm, belonging to 2B type. The chromosomes are small except the medium-sized, 1st pair and the range is from 1.27 to 5.19μm. The material from Mt. Yuling, Zhejiang, is found to have a variety of chromosome numbers (2n= 60-71), as observed in Ophiopogon japonicus. Hasegawa (1968) reported the karyotype of 2n = 72 (4x) from Japan The 2x karyotype is first recorded. This genus is closely related to Ophiopogon. Based on the Hasegawa’s and present studies, all the species in these two genera are remarkably uniform in karyo-type. Therefore, the taxonomy of the two genera is worth further researches.     

不同地域乌拉尔甘草基因组的FISH分析与染色体识别

在核型分析与染色体识别基础上,分别以番茄45S和5S rDNA为探针,对3种不同地域的乌拉尔甘草进行FISH分析.结果表明:内蒙古鄂托克前旗的乌拉尔甘草核型公式为2n=2x=16=6m+10sm (2SAT),新疆阿勒泰地区的乌拉尔甘草核型公式为2n=2x=16=4m+12sm(2SAT),内蒙古喀喇沁旗乌拉尔甘草核型公式为2n=2x=16=4m+12sm(2SAT);其第8染色体均带有随体.3种乌拉尔甘草基因组内均有1对5S rDNA和1对45S rDNA杂交位点.核型分析显示,5S rDNA杂交位点均位于第2染色体的短臂部位,45S rDNA杂交位点均位于第8染色体的次缢痕和随体部位.45S与5S rDNA在3种乌拉尔甘草中期分裂相上的位点数和分布情况高度一致,表明来自3种不同地域的乌拉尔甘草在染色体结构水平上没有较大的分化.     

Cytogenetics characterization of <Emphasis Type="Italic">Crenuchus spilurus</Emphasis> (Günther, 1863): a remarkable low diploid value within family Crenuchidae (Characiformes)

Conventional and molecular cytogenetic analyses were performed in specimens of the Neotropical Crenuchus spilurus freshwater fish species from a single location (Caeté River, Brazil). All specimens presented diploid values of 2n?=?38 chromosomes (12 m?+?4sm?+?2st?+?20a), the lowest reported for family Crenuchidae up to now. A single pair of nucleolar organizing regions (NORs) was detected in the subtelocentric chromosome pair no. 9 by silver-staining and fluorescence in situ hybridization (FISH) with 18S rDNA sequence-specific probe. Two pairs of 5S rRNA gene clusters were found either interstitial or terminally located in the long arms of the acrocentric chromosome pairs nos. 10 and 13. Heterochromatic regions were clearly observed in the short arms of the NOR-bearing chromosome pair and weakly-positive to the pericentromeric regions of most acrocentric chromosomes. Additionally, no sex chromosomes were identified in the surveyed specimens. Crenuchidae have signals of several mechanisms involved in karyotype diversification within this family: differential location of heterochromatin-rich regions, multiplication, and translocation of rDNA clusters, presence/absence of sex chromosomes, macrostructural changes in morphology and number of chromosomes. This variety of karyotype patterns reveals the importance of widening cytogenetic studies to more taxa for better know the chromosomal evolution occurred in this group.     

Karyotypic studies in Solanum section Lasiocarpa (Solanaceae)

Mitotic chromosomes of 13 species included in Solanum sect. Lasiocarpa were studied. All species have 2n = 24. The chromosome numbers of S. stagnale, S. felinum, and S. repandum are reported for the first time. Statistical analyses of chromosomes, genome length, and centromere position yielded estimates of karyotype composition and asymmetry. A generalized karyotype of the section shows that most of the chromosomes are metacentric (73%) or submetacentric (25.6%). Two pairs of subtelocentric chromosomes are present only in S. sessiliflorum. Satellites are quite common, characterizing chromosomes for ten species and are attached to the short arms of either m or sm chromosomes. They could be seen in 10% to 70% of the cells. Only S. pseudolulo bears two satellited chromosomes, one of them attached to a long chromosome arm. Although the section is chromosomally quite homogeneous, species can be distinguished by karyotype formula, presence of satellites in a particular chromosome pair, and total chromosome length. There are no indications of major chromosomal rearrangements within the section. Using cytological data exclusively, cluster analysis indicates S. sessiliflorum is isolated in the section. Solanum candidum and S. vestissimum are somewhat isolated as well and have unique karyological traits. Solanum pectinatum has a peculiar karyotype, but in the phenogram it is not particularly separated. Karyotype features suggest that morphological differentiation was not always followed by chromosomal divergence. The origin of the domesticated S. quitoense is no further elucidated by our data.     

Heterochromatic chromosomes and satellite DNAs of Drosophila nasutoides

Drosophila nasutoides is distinguished from other Drosophila species in that the metaphase karyotype shows a pair of very large V-shaped chromosomes. With Giemsa, a distinctive C-banding pattern is revealed along the arms of this large chromosome, indicating a largely heterochromatic nature. Furthermore, the banding patterns of the arms are symmetrical, indicating that it is an iso-chromosome. A comparison between the metaphase karyotype and polytene chromosomes suggests that the large V chromosome appears as the dot chromosome in polytene squash. One autosome has twice the arm length of typical Drosophila polytene chromosomes and arose either by centric fusion and a pericentric inversion, or by translocation connecting distal ends with a subsequent loss of one centromere. This chromosome appears to have a short arm which ectopically pairs with the proximal region of the long arm, representing a duplication of about ten bands. When the nuclear DNA is examined by neutral CsCl gradient, four satellites are observed. As much as sixty percent of the total DNA appears as satellites in the lysate of larval brains. No satellite was detectable in the lysate of salivary glands. These observations led us to suggest that the heterochromatic nature of the large V chromosome is due to the presence of all four satellites in this chromosome and that this large chromosome appears as the dot because of the under-reduplication of the satellites during polytenization.     

海岛棉原位杂交及核型比较

采用Ａ染色体组（Ａ genome)棉种亚洲基因组ＤＮＡ（gDNA)为探针,对海岛棉体细胞染色体进行荧光原位杂交（ＦＩＳＨ）,结果发现５２条染色体中有杂交信号与否的刚好各一半,从而直观地证实了海岛棉异源双二倍体起源的理论,但是,染色体的长度Ａ亚组的并非全部大于Ｄ亚组的。海岛棉基于ＦＩＳＨ图像的核型公式为：２n=4x=52=38m 14sm(sat)。３对随体染色体序号分别是Ａ亚组第１１、Ｄ亚组第２２和２５,均属于近中部着丝点（sm)类型,随体均在各自杂色体的短臂上,而且与所有染色体无关晨同一亚组起源。Ａ亚组第５、６和９对染色体长臂发生长了片段的易位,易位的片段较大,占所在染色体和蔗的百分率依次为１９．２１％、１７．６９％和１２．８８％,在Ｄ亚组１３对染色体中,最少５对的着丝点区域多或少地显示出与亚洲棉gDNA探针杂交的红色荧光信号,意味着有Ａ亚组染色体的交换。     

Karyotypic variability in Iheringichthys labrosus (Teleostei, Pimelodidae) from the Tibagi River basin (Paraná State, Brazil)

Cytogenetic analyses were carried out in a populational sample of Iheringichthys labrosus from the Guaraúna River (Upper Tibagi River; Paraná State, Brazil) in order to provide a karyotypic comparison with another previously studied population from the Lower Tibagi River, characterized by the presence of 32m + 8sm + 6st + 10a (2n = 56, FN = 102) and occurrence of supernumerary chromosomes (80% of individuals). The 17 specimens of I. labrosus (6 females, 10 males and 1 of unknown sex) from the Upper Tibagi River showed 2n = 56 chromosomes, a karyotype formula of 14m + 32sm + 4st + 6a (FN = 106), without evidence of sex chromosome heteromorphism or supernumerary chromosomes. The heterochromatin was detected at telomeric and centromeric positions in several chromosomal pairs. The Ag-nucleolar organizer regions were heteromorphic and located at terminal position on short arms of the 16th chromosomal pair, suggesting a positive association with heterochromatic regions. The inter-populational karyotypic differentiation reported indicates distinct evolutionary pathways within I. labrosus in the Tibagi River basin.