黄精属细胞分类学研究Ⅱ.四川金佛山地区黄精属植物核型

本文对四川金佛山地区4种黄精属植物的核型进行了研究,其结果为:滇黄精:2n=26=6m+12sm(2SAT)+8st(2SAT);距药黄精:2n=26=10m+4sm+12st;垂叶黄精:2n=30=14m(2SAT)+4sm+10st+2t、2n=28=14m+6sm+6st+2t;湖北黄精:2n=30=12m+8sm+10st、2n=28=6m+10sm+10st+2t、2n=22=2m+12sm 8st。通过与其它地区黄精属植物染色体数目与形态的比较,发现本地区所有种类的染色体数目普遍偏高,无论在染色体基数或染色体形态上都比较接近喜马拉雅山地区分布的种类。从实验结果进一步看出了黄精属的染色体变异是相当明显的,并主要表现为非整倍性变异;在有些情况下,染色体数目与结构的变异能与某些形态学特征相联系。     

黄精属细胞分类学研究——Ⅱ.四川金佛山地区黄精属植物核型

本文对四川金佛山地区4种黄精属植物的核型进行了研究,其结果为:滇黄精:2n=26=6m+12sm(2SAT)+8st(2SAT);距药黄精:2n=26=10m+4sm+12st;垂叶黄精:2n=30=14m(2SAT)+4sm+10st+2t、2n=28=14m+6sm+6st+2t;湖北黄精:2n=30=12m+8sm+10st、2n=28=6m+10sm+10st+2t、2n=22=2m+12sm 8st。通过与其它地区黄精属植物染色体数目与形态的比较,发现本地区所有种类的染色体数目普遍偏高,无论在染色体基数或染色体形态上都比较接近喜马拉雅山地区分布的种类。从实验结果进一步看出了黄精属的染色体变异是相当明显的,并主要表现为非整倍性变异;在有些情况下,染色体数目与结构的变异能与某些形态学特征相联系。     

合欢核型的分析

应用根尖压片法对含羞草科合欢属合欢的染色体数目和核型进行了研究,结果表明:合欢体细胞染色体数目为2n=26,核型为:2n=26=18m 6sm 2st,属于“2B”类型。染色体相对长度组成为2n=26=4L 8M2 12M1 2S。从染色体水平证明合欢在系统演化上属于较进化的种类。     

三尖叶猪屎豆染色体核型分析

本文以三尖叶猪屎豆(Crotalaria anagyroides H.B.K)根尖为试验材料,对其染色体核型及数目进行了研究。研究结果表明:三尖叶猪屎豆体细胞染色体数目为2n=16。染色体组总长度为26.62微米,全部的染色体为中部着丝点,除在第8对染色体上发现有一随体外,其余均没有发现随体和次缢痕。按Levan的染色体分类标准,其染色体核型组成是K(2n)=16=14m+2m_8~(sat)。     

裸体方格星虫染色体组型分析

将裸体方格星虫(Sipunculus nudus)置于0.04%秋水仙素溶液中暂养12h,取其体腔液,用盐度6.50‰过滤海水低渗45min,1500r/min离心8min,卡诺氏液固定1h,热滴片,5% Giemsa染色,显微观察、摄影,根据Levan等的分类标准进行染色体组型分析.结果表明,裸体方格星虫的染色体基数为x=17,2n=2x=34,染色体组型为2n=2x=26m 8sm,NF=68.除第2、3、4、8对染色体为亚中部着丝粒染色体(sm)外,其余均为中部着丝粒染色体(m).臂比值变化范围是1.211～2.617.未发现性染色体和随体.     

蜘蛛染色体单一胚胎压片观察

利用单一胚胎压片法制备蜘蛛染色体取得了很好的结果。此法可以迅速确定蜘蛛染色体的性比,同时对于精巢特别小的蜘蛛染色体制备特别有用。所研究的蜘蛛染色体数目为:纵条蝇狮(Marpissa magister)2n=28()和26(),角园蛛(Araneus cornalus)2n=26()和24();2n=26和25();2n=24和33(),显示染色体多态型。     

五叶风藤茎尖染色体核型分析

用五叶风藤 (HolboelliafargesiiReaub)茎尖染色体制片 ,研究其染色体组型 ,结果表明 :五叶风藤的染色体组型公式为 2n =2x =16 =12m 4sm ,染色体基数x =8,第 4号染色体上有一对染色体随体 ,核型为 2B类型 ,其中 2n =4x =32 =2 4m 8sm的四倍性细胞相当普遍。     

陆地棉和海岛棉染色体组型比较

棉花染色体组型的研究,已有人做过工作,如Eduards曾研究了草棉(Gossypium nerbaceum var.africanum)2n=26和两种澳大利亚野生棉(G.bickii;G.sturticanum)2n=26染色体组型;陈瑞阳、聂汝芝、李懋学等人均在这方面做了工作。我们也对陆地棉(G.hirsutum)和海岛棉(G.barbadense)进行了核型分析,结果如下:     

北五味子染色体核型分析

本文研究了北五味子的染色体核型.其体细胞染色体数目2n=28,具13对中部着丝点染色体,1对近中部着丝点染色体.在整个染色体中并未发现随.按Levan的染色体分类标准,其染色体核型组成是:K(2n)=2x=28=26m+2Sm.     

五叶风藤茎尖梁色体核型分析

用五叶风藤（Holboellia fargesii Reaub）茎染色体制片,研究其染色体组型,结果表明：五叶风藤的染色体组型的公式为2n=2x=16=12m 4sm,染色体基数x=8,第4号染色体上有一对染色体随体,核型为2B类型,其中2n=4x=32=24m 8sm的四倍性细胞相当普遍。     

寒露林蛙的核型和Ag-NORs研究

采用常规骨髓细胞制片法对产于湖南省双牌县的寒露林蛙的核型及NORs位点进行了观察和分析.结果表明寒露林蛙与分布于我国南方的其他林蛙相同:2n=26,NF=52,为5+8核型模式.寒露林蛙核型为14M+10SM+2ST,无次溢痕,NORs位于第11对染色体长臂的中部.通过比较分析我国2n=26的6种林蛙的核型等细胞遗传学信息,本文结果支持形态分类和分子系统发生的研究结论,认为寒露林蛙是一有效种.     

Evidence for chromosome number reduction and chromosomal homosequentiality in the 24-chromosome Korean frog Rana dybowskii and related species

The karyotype of the Korean frog Rana dybowskii with its pattern of C-band heterochromatin distribution was numerically analyzed. There are 2n = 24 chromosomes in the karyotype representing a reduction in number from the typical 2n = 26 chromosome karyotype of Rana. The karyotype shows other evidence of reorganization relative to 26-chromosome species. The chromosomes grade smoothly in size from largest to smallest without the two size classes that are characteristic for 26-chromosome species. In contrast to many 26-chromosome species, there are few centromeric C-bands but many interstitial ones. C-bands for each homologous chromosome pair are distinctive. A prominent secondary constriction is located on one of the smallest chromosomes, chromosome 11, in a position similar to that seen in most 26-chromosome species. The karyotype of R. dybowskii is compared to those of other species of Rana known to have 2n = 24 chromosomes; it is most similar to that of R. chensinensis, less so that of R. ornativentris and less still to that of R. arvalis in terms of the positions of centromeres and secondary constrictions. C-bands as well as secondary constrictions in the karyotypes of these frogs show evidence of chromosomal homosequentiality. The process and possible consequences of chromosome number reduction from an ancestral 26-chromosome karyotype is also evident in the karyotypes of these closely allied palearctic frogs. Pericentric inversions followed by fusion of two small elements apparently produced a new chromosome, chromosome 6, occurring originally among northeast Asian populations.     

Karyotype study of Rana camerani and comparisons with the other 26-chromosome European brown frog species (Amphibia, Anura).

The results of a detailed morphological and morphometrical chromosome analysis of Rana camerani (2n = 26) are described. It was established that the karyotype of this species consisted of three homologous pairs of large metacentrics, two homologous pairs of large submetacentrics, three homologous pairs of small metacentrics, two homologous pairs of small submetacentrics, and three homologous pairs of small subtelocentrics. Morphologically discernible sex chromosomes were not found. The similarity and peculiarities in the R. camerani karyotype and those of R. temporaria, R. dalmatina and R. graeca are discussed. This comparative karyotype analysis has suggested the possibility for developing a general chromosomal formula, by means of which these 26-chromosome species could be characterized.     

黑斑蛙核型、C-带及Ag-NORs 研究

本文采用外周血淋巴细胞培养法制备染色体标本,观察黑斑蛙的染色体标本,研究黑斑蛙的核型,C-带和Ag-NORs。研究结果表明：（1）黑斑蛙淋巴细胞染色体数目为2n=26,其中有5对大染色体和8对小染色体,核型是二型性核型;（2）分别对雌雄个体的中期分裂相进行观察,在第11号染色体长臂中部有明显的次缢痕,但变异核型次缢痕在第8号染色体长臂的中部;（3）在第5号染色体长臂上有一条明显的近端粒C-带;（4）第11号染色体是一对具有银染核仁形成区的同源染色体,且雌雄个体的银染位置相同。     

Can an Invasive Prey Species Induce Morphological and Behavioral Changes in an Endemic Predator？ Evidence from a South Korean Snake （Oocatochus rufodorsatus）

Introduction of an invasive prey species into an ecosystem may affect an endemic predator＇s fitness by altering the prey-predator system. Successful adaptation may allow the endemic predator to eat and control the invasive species, while unsuccessful adaptation may result in extinction of the predator. We examine the possible effects of the invasive North American bullfrog （Rana [Lithobates] catesbeiana） on the endemic Red-backed rat snake （Oocatochus rufodorsatus） in South Korea. We do so by comparing the morphology and behavior of adult and hatchling snakes from bullfrog-exposed （Taean） and bullfrog-unexposed （Hongcheon） populations. Among the seven morphological characteristics investigated, relative tail length （tail length/snout-vent length） of both adults and hatchlings from Taean was significantly greater than that of adults and hatchlings from Hongcheon. Also, adult snakes from Taean had a signiifcantly shorter latency of ifrst tongue lfick in response to prey compared to adults from Hongcheon. This difference was not observed in hatchlings. In other snake species, a longer relative tail length and shorter latency of ifrst tongue lfick are known to improve foraging efifciency, and these characters may be adaptations ofO. rufodorsatus to prey on bullfrogs. This study provides preliminary evidence that the presence of an invasive prey species may cause morphological and behavioral changes in an endemic predator.     

Cloning of hibernation-related genes of bullfrog (Rana catesbeiana) by cDNA subtraction

Seven genes specifically expressed during hibernation in the bullfrog (Rana catesbeiana) were cloned from a subtracted cDNA library constructed from livers of winter bullfrogs. Those genes were fibrinogen alpha-subunit, fibrinogen gamma-subunit, complement component C3, alpha-1-microglobulin/bikunin precursor (AMBP), transferrin, apoferritin middle subunit and one novel gene. Northern hybridization has indicated that these seven genes were specifically induced or enhanced in winter. Above all, expression of the novel gene was specifically induced in winter in liver, though the expression of that was neither induced in bullfrog nor Xenopus laevis by cold treatment. The novel gene, which was designated as rc-hirp (Rana catesbeiana hibernation-related protein), encoded 420 base pairs length and a putative protein of 139 amino acid residues. Annual analyses of the expression of these genes have suggested that the seven winter-specific genes are playing an important role in hibernation processes.     

长叶竹柏核型的初步研究

本文对长叶竹柏核型进行了初步研究,结果表明,长叶竹柏染色体的数目为2n=26。第8、10、11、13对染色体为中部着丝点染色体,其余9对均为近中部着丝点染色体,且在第2对染色体长臂上具次缢痕;按Stebbins的分类标准,属较对称的“zA”核型。其染色体的绝对长度范围为3.32—6.39μm,相对长度范围为5.33—10.26%。     

蛙属三种的核型研究

本文研究了蛙属三种：脆皮蛙、长趾蛙和威宁蛙的染色体核型,结果表明均具有蛙属典型的核型：2n=26,由5对大染色体和8对小染色体组成。三种在臂比值和次缢痕的有无、位置方面存在差异。同源染色体对间未发现异形现象。     

Karyotypes of Rana tagoi Okada with diploid number 28 in the Chausu Mountains of the Minamishinshu district of Nagano Prefecture, Japan (Anura: Ranidae)

Karyotypes of Tago's brown frog Rana tagoi from the Chausu mountains in Minamishinshu of Nagano Prefecture were examined by conventional Giemsa staining, C-banding and late replication (LR)-banding. Chromosome number was 2n = 28 in all cases. The 28 chromosomes consisted of four pairs (1-4) of large biarmed chromosomes, two pairs (5-6) of telocentric chromosomes and eight pairs (7-14) of small biarmed chromosomes. Chromosome pair 11 had a secondary constriction on the long arm. In females, the C-band on the long arm of chromosome pair 6 was detected in both homologs, but was absent from the arms of the homologs of chromosome pairs 5 and 9. In males, C-bands were found in the long arms of both homologs of chromosome pairs 5 and 6, were present only in one homolog of chromosome pair 5 for certain male specimens and found in only one homolog of chromosome pair 9. Specimens of R. tagoi (2n = 28) should thus have two pairs of telocentric chromosomes to provide the same number of chromosome arms, these originating quite likely from chromosome pair 1 in the 26-chromosome specimens by centric fission. Heteromorphic sex chromosomes of the XX-XY type in R. tagoi (2n = 28) in the Chausu mountains were identified. Karyotypes of tail-tip cells from a hybrid tadpole between female R. tagoi (2n = 26) from the Hinohara village in Tokyo and male R. tagoi (2n = 28) from the Chausu mountain population were examined by squash preparation. Chromosome number was 2n = 27 in all tadpoles. The 27 chromosomes consisted of one chromosome set of R. tagoi (2n = 28) and one of R. tagoi (2n = 26).     

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.