稀莶属三种植物的核形态学研究

研究了稀莶属３种植物的染色体核形态结构,除稀莶的染色体数目曾有报道外,毛梗稀莶、腺梗稀莶还未有报道,３种植物的核型为首次报道。它们的静止核均属于复杂染色中心微粒型,分裂前期染色体均属于渐变型。中期体细胞染色体数目都为２ｎ＝３０,本属的染色体基数为ｘ＝１５,核型分别为：（１）腺梗稀莶２ｎ＝３０＝２９ｍ＋１ｓｍ,属于１Ｂ型;（２）毛梗稀莶２ｎ＝３０＝２８ｍ＋２ｓｍ,属于１Ｂ型;（３）稀莶２ｎ＝３０＝２     

新疆猪毛菜属4种植物核型分析及进化研究

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

A Cytological Study of Six Populations of Disporum cantoniense (Liliaceae)

Disporum cantoniense (Lour.) Merr. is widely distributed in the area from the Himalayas to Indonesia, via south China, Indo-China and Taiwan, especially in the various parts of Yunnan Province. In this paper, the karyotype variation of six populations of the apecies from southeastern, middle and northwestern part of Yunnan are studied. The result shows that the chromosome number of all the populations are 2n= 14. The species was reported to have 2n= 16, 30 (Hasegawa 1932, Mehra and Pathamia 1960, Kurosawa 1966, 1971, Tang et al. 1984) and 2n= 14 (Kurosawa 1971, Mehra and Sachdeva 1976a). 2n= 14, 2n= 16 and 2n=32 were observed in the material from Taiwan (Chuang, et al. 1962, Chao, 1963, Hsu, 1971, 1972, Chang, 1974). Based on the cytological study of D. megalanthum Wang et Tang and seven other species in this genus reported by other authors, Hong and Zhu (1990) consider that the basic number of this genus is x= 8, because species with 2n= 16 was more than those with 2n= 14, despite some number variation of chromosomes in this genus. Based on the results of the present paper, we consider that x= 7 might be one of the basic numbers of this genus. In the karyotypes studied here, the relative chromosome lengths and the ratio of the longest/the shortest chromosomes of the six populations are rather approximate. Moreover, all the karyotypes belong to Stebbins’3B type. However, karyotype variation was detected in these populations. The homologues of the 2nd, 3rd and 6th pair of chromosomes are different from each other, the numbers and popsition of satellites are found very different, among the populations except for the Lijiang population, the 1st, 2nd, 3rd or 4th pair of all the populations exhibited heterozygosity. Although all the karyotypes belong to Stebbins ‘3B type, the homologues were more regular in the Lijiang population than in the other populations, and the most irregular in the Wenshan population, because it hadfour pairs of heterozygous chromosomes.     

青藏高原六种棘豆属植物的染色体数目及核型报道

对6种棘豆属植物（Oxytropis）的13个居群样进行细胞学研究,其中黄花棘豆（O．ochrocephala）、绢毛棘豆（O．tatarica）、甘肃棘豆（O．kansuensis）和铺地棘豆（0．humifusa）为首次报道染色体数目（2n=16）和核型;在胀果棘豆（O．stracheyana）中（2n=48）首次发现B染色体。现有的细胞学资料表明：棘豆属植物中多倍体占总报道数的58％,这说明多倍化在本属植物的进化过程中起着非常重要的作用,但青藏高原仅有一种植物发现多倍体,多倍化并不占主导地位,而主要表现为二倍体水平上的结构变异,即核型不对称性的变化。     

Uniformity of karyotypes in Ligularia (Asteraceae: Senecioneae), a highly diversified genus of the eastern Qinghai–Tibet Plateau highlands and adjacent areas

Ligularia , a highly diversified genus in the eastern Qinghai–Tibet Plateau and adjacent areas, was chosen as a suitable subject in which to study speciation patterns in this 'hot spot' area at the chromosomal level. Chromosome numbers and karyotypes were studied in 23 populations of 14 species, most of which are endemic to this area. The basic number x  = 29 was confirmed for all species. Ligularia virgaurea was found to have diploid and triploid cytotypes, 2 n  = 58 and 87. Other species are only diploid, with 2 n  = 58. The karyotypes of all populations within any species, and all species spanning most sections and covering most of the morphological range in Ligularia , are very similar to each other, belonging to type 2A according to Stebbin's classification. This karyotype was also found in its close allies, e.g. Cremanthodium , Ligulariopsis , Parasenecio , and Sinacalia . Aneuploid reduction of chromosome number from 2 n  = 60 to 58 and karyotypic variation was found in Ligularia and its allies. Such a chromosomal pattern with few polyploids infers that variation of karyotype structure at the diploid level seems to be the predominant feature of chromosomal evolution in this group and sympatric speciation via hybridization and polyploidization has played a minor role in its species diversity.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 329–342.     

Chromosome Numbers and Karyotypes of Six Oxytropis Species (Fabaceae) from the Qinghai Tibetan Plateau,China

Chromosome numbers and karyotypes of 13 populations of six Oxytropis species (Fabaceae) from the Qinghai Tibetan Plateau, China, were presented. The chromosome numbers and karyotypes in O.ochrocephala, O.tatarica, O.kansuensis and O.humifusa (2n=16) were reported for the first time. B chromosomes were found from O.stracheyana (2n=48). The basic chromosome number of x=8 is confirmed for the genus. The available chromosomal data indicate that polyploidy may have played an important role in the evolution of the genus, with the incidence of polyploidy in the genus reaching 58%. However, our results indicated that among the populations here examined only one was a hexaploid with 2n=48. Such a chromosomal pattern indicates that the karyotypic repatterning at the diploid level seems to be the predominant feature of chromosomal evolution in the Oxytropis species from the Qinghai Tibetan Plateau, and that sympatric speciation via hybridization and polyploidization has played a minor role in the species diversification of the genus from this area.     

八种国产大戟属植物的核型报道

8种大戟属Euphorbia L．植物的核型分析结果表明,大戟属不同亚属的染色体基数与其形态变 异的复杂性有一定关系。地锦草亚属subgen．Chamaesyce 3个种染色体基数分别为x=8,9,11;一品红 亚属subgen．Poinsettia两个种染色体基数均为x=7,分别为四倍体和八倍体;乳浆大戟亚属subgen． Esula 3个种,染色体基数分别为x=7,10,10。根据以前学者发表的资料分析,一品红亚属和大戟亚属 Subgen. Euphorbia的染色体基数是很稳定的,分别为x=7和x=10;通奶草E．hypericifolia为x=8 的四倍体,它不仅有染色体整倍性的变异,还有异基数性的变化。结合以前学者的研究,笔者支持x= 10为大戟属的最原始基数的观点。齿裂大戟E．dentata和通奶草具不同的染色体倍性,猫眼草E． esula的细胞染色体数目观察证实了我国存在四倍体的居群,与欧洲和北美的植物构成一个典型的多倍体复合体。     

Karyotypes of eight species of Euphorbia L. (Euphorbiaceae) from China

In this paper, eight species of the genus Euphorbia L. were cytologically studied. The three species of the subgenus Chamaesyce Raf., E. hirta, E. humifusa and E. hypericifolia, had chromosome numbers of 2n = 18, 22 and 32, with their basic chromosome numbers being x = 9, 11 and 8 respectively. The two species of the subgenus Poinsettia (Grah.) House. E. dentata, with 2n=28, a tetraploid, and E. cyathophora, with 2n= 56, a octoploid, had both the basic chromosome number of x= 7. The three species of the subgenus Esula Pers, E. lathyris, E. helioscopia and E. hylonoma, had chromosome number of 2n= 20, 42 and 20, with their basic numbers being x= 10, 7 and 10 respectively. The basic chromosome number of x = 8 is new for E. hypericifolia, in which x = 7 was previously reported. This indicates that this species had both ploidy(2n = 4x = 28, 8x = 56) and dysploidy(x = 7, 8) variations. In E. dentata, there occurred also ploidy variation (2n = 2x, 4x and 8x). A tetraploid cytotype of E. esula was found in China, its diploid cytotype and hexaploid cytotype being previously reported in North America, the Iberian Peninsula and some other European areas. Based on our results and those previously reported, we support the viewpoint that x＝10 may be the original basic chromosome number of Euphorbiaand discuss the role of polyploidy and dysploidy in the speciation and evolution of this genus     

横断山区伞形科4种7个居群植物的核型研究

对横断山区伞形科棱子芹属2种植物(松潘棱子芹Pleurospermum franchetianumHemsl.和西藏棱子芹Pleurospermum hookeriC.B.Clarke var.thomsoniiC.B.Clarke)和茴芹属2种植物(异叶茴芹Pimpinella diversi-foliaDC.和锐叶茴芹Pimpinella argutaDiels)共7个居群进行体细胞染色体数目观察和核型比较分析,结果表明,棱子芹属和茴芹属植物属内种间染色体基数存在差异,其中松潘棱子芹为2n=2x=18=16sm 2st,西藏棱子芹为2n=2x=22=16m 6sm;茴芹属光果组中锐叶茴芹为2n=2x=22=22m,毛果组中异叶茴芹为2n=18=18st或2n=18=2sm 16st.松潘棱子芹、西藏棱子芹、锐叶茴芹的染色体数目和核型均为首次报道,从而为棱子芹属和茴芹属的分类和演化研究提供细胞学依据.     

国产８种蜘蛛抱属植物的核型研究

首次报道了８种蜘蛛抱属植物的核型,其中６种的染色体数目为首次报道,结果如下：峨边蜘蛛抱蛋Ａ.ebianensis,2n=2x=36=18m 2sm(2sat) 16st;盈江蜘蛛抱蛋Ａ．yingjiangensis,2n=2x=36=14m 6sm(2sat) 16st;海南蜘蛛抱蛋Ａ．hainensis,2n=2x=36=20m(2sat) 14st 2t;石山蜘蛛抱蛋Ａ.saxicola,2n=2x=36=16m 4sm(2sat) 16st;要蜘蛛抱蛋白Ａ.muricata,2n=2x=36=18m 2sm(2sat) 16st);啮边蛛抱蛋Ａ.marginella,2n=2x=38=22m 4sm(2sat) 12st;西林蜘蛛抱蛋Ａ.xillinensis,2n=4x=76=48m(4sat) 2sm 26st;十字蜘蛛抱蛋A.cruciformis,2n=4x=76=46m(4sat) 12sm 18st。核型类型都为２Ｃ型。首次在中国发现了Ａ.cruciformis和A.xilinensis的野生四倍体。根据外部形态性及已有的３８种植物的核型资料分析,认为该属染色体的原始基数可能为x=18,核型向对称性增强的方向演化,其主要表现在中部着丝粒染色体数目的增多,这种演化趋似与其花部结构的进化密切相关。     

Chromosome number variation and evolution in Neotropical Leguminoseae (Mimosoideae) from northeastern Brazil

Most members of the subfamily Mimosoideae have pantropical distributions, variable habits, and a basic chromosome number x = 13. We examined karyotypic evolution of 27 species of this subfamily occurring principally in northeastern Brazil by examining chromosomes stained with Giemsa. All of the species had semi-reticulated interphase nuclei and early condensing segments in the proximal region of both chromosome arms. The basic number x = 13 was the most frequent, with 2n = 2x = 26 in 19 of the species, followed by 2n = 4x = 52 and 2n = 6x = 78. However, the three species of the genus Calliandra had the basic number x = 8, with 2n = 2x = 16, while Mimosa cordistipula had 2n = 4x = 32. The karyotypes were relatively symmetrical, although bimodality was accentuated in some species, some with one or two acrocentric pairs. As a whole, our data support earlier hypotheses that the Mimosoideae subfamily has a basic number of x = 13 and underwent karyotypic evolution by polyploidy. However, x = 13 seems to be a secondary basic number that originated from an ancestral stock with x(1) = 7, in which polyploidy followed by descending disploidy gave rise to the current lineages with x = 13. Another lineage, including current representatives of Calliandra with x = 8, may have arisen by ascending disploidy directly from an ancestral monoploid stock with x(1) = 7.     

锦鸡儿属3种植物的核型研究

以锦鸡儿属中间锦鸡儿、柠条锦鸡儿、狭叶锦鸡儿为材料,用光学显微镜观察了3种锦鸡儿的染色体,按全国第一次植物染色体学术讨论会建议的标准进行了核型分析。结果表明,3种锦鸡儿的体细胞染色体数目2n=16,核型公式分别为:中间锦鸡儿2n=2x=16=10m 6sm、柠条锦鸡儿2n=2x=16=12m 4sm、狭叶锦鸡儿2n=2x=16=14m 2sm,中间锦鸡儿和柠条锦鸡儿的核型属于2A型,狭叶锦鸡儿的核型属于2B型。狭叶锦鸡儿二倍体染色体核型为首次报道。     

Karyotype analysis in Brachiaria (Poaceae) species

This is the first karyotype characterization of Brachiaria species. Twelve accessions belonging to five species were analysed. The basic chromosome number was x = 9 and 7, the same reported for the tribe Paniceae. Variations in the chromosome number were observed in B. decumbens (2n = 18; 36) and B. humidicola (2n = 36; 42; 54). Chromosome numbers of 2n = 18 in B. ruziziensis and 2n = 36 in B. brizantha and B. jubata were recorded. Inter- and intraspecific karyotype differentiation of the accessions analysed was facilitated by variations in karyotypic symmetry. The karyotypes were generally considered symmetrical, with a tendency to asymmetry in the direction of the polyploids. It is suggested that addition, deletions and mainly polyploidy have been the most direct causes involved in the chromosome evolution of this genus.     

5种珍珠菜属植物的核型分析

对 5种珍珠菜属 (LysimachiaL .)植物的核型进行了研究 ,其中巴东过路黄 2n =2x =2 4 =6m 4sm 6st 8t、光叶巴东过路黄 2n =2x =2 4 =6m 4sm 6st 8t、临时救 2n =2x =2 4=2m 4sm 4st 14t的核型属首次报道。过路黄 2n =2x =2 4 =2m 4sm 6st 12t和星宿菜2n =2x =2 4 =2 0m 4sm与前人报道的一致。本文还对该属已报道的 17种植物的核型资料进行了总结和比较分析 ,对珍珠菜属植物的核型进化方向作了初步推测。另外对一存疑过路黄(2n =2x =2 4 =2m 6sm 4st 12t)与其近缘种的核型进行了比较研究。     

国产8种蜘蛛抱蛋属植物的核型研究

首次报道了8种蜘蛛抱蛋属植物的核型,其中6种的染色体数目为首次报道。结果如下：峨边蜘蛛抱蛋A．ebianensis,2n=2x=36=18m+2sm(2sat)十16st;盈江蜘蛛抱蛋A．yingjiangensis,2n=2x=36=14m+6sm(2sat)十16st;海南蜘蛛抱蛋A．hainanensis,2n=2x=36=20m(2sat)十14st十2t;石山蜘蛛抱蛋A．saxicola,2n=2x=36=16m十4sm(2sat)十16st;糙果蜘蛛抱蛋A．muricata,2n=2x=36=18m+2sm(2sat)十16st;啮边蜘蛛抱蛋A．marginella,2n=2x=38=22m+4sm(2sat)十12st;西林蜘蛛抱蛋A．xilin-ensis,2n=4x=76=48m(4sat)十2sm+26st;十字蜘蛛抱蛋A．cruciformis,2n=4x=76=46m(4sat)十12sm十18st。核型类型都为2C型。首次在中国发现了A．cruciformis和A．xilinensis的野生四倍体。根据外部形态性状及已有的38种植物的核型资料分析,认为该属染色体的原始基数可能为x=18,核型向对称性增强的方向演化,其主要表现在中部着丝粒染色体数目的增多,这种演化趋势似与其花部结构的进化密切相关。关键词 蜘蛛抱蛋属;染色体数目;核型;进化     

天南星科斑龙芋属植物的核型研究

报道了天南星科（Araceae)斑龙芋属（Sauromatum)两种植物的型,它们的静止核均为渐变型,分裂前期染色体均为中间型,体细胞中期染色体均为2n=26,核型分别为：斑龙芋（S.venosum)2n=2x=26=14m 12sm;高黎贡山斑龙芋（S.gaoligongense)2n=2x=26=10m 12sm 4st,其中高黎南山斑龙芋的染色体数目和核型为首次报道。本文还就斑龙芋属的分类地位进行了初步讨论,认为在尚未进行更详细的、多方面的综合研究之前,仅从一些形态上的相似性就匆忙将斑龙芋属归并到犁头尖属是值得商榷的,并从珠芽和细胞学两方面的特性推断属与半夏属可能有较近的亲缘关系。     

Karyotypes and C-values of Two Plantago Species from the Qinghai Tibet Plateau,China

The chromosome numbers, karyotypes and C values of 18 populations of Plantago depressa and 2 populations of Plantago major from the Qinghai Tibet Plateau, China, were reported in the present study. The results were as follows: the chromosome numbers of P. depressa populations from Yadong County and Nyingchi County of Tibetan Autonomous Region (TAR) were 2n=4x=24, other populations of Pdepressa and Pmajor were 2n=2x=12, and the basic chromosome number of all populations was x=6. All karyotype types were 1A, and the karyotype constitutions were not completely consistent with previous reported results. The 2C value of Pdepressa was reported for the first time, and the 1Cx vaule tended to decrease with increasing ploidy levels. Meanwhile, the 2C value of Pmajor was not identical with previous existing results. The results showed that the variation of 2C value occurred at the inter population level of Pdepressa and Pmajor, also flow cytometry couldn′t be used to estimate the ploidy of the genus Plantago Linn.     

百合科开口箭属六个种的核型研究

本文报道了开口箭属(Tupistra)6个种的核型,发现6个种皆为二倍体,染色体数目为38。他们的核型公式是:弯蕊开口箭(T. wattii)为2n=2x=38=38m;长梗开口箭(T. longipeduncuJara)为2n=2x=38=28m 10sm;橙花开口箭(T. aurantiaca)为2n=2x=38=22m 16sm;开口箭(T. chinensis)和云南开口箭(T. yunnanensis)皆为2n=2x=38=24m 14sm,核型皆为2B型,但sm染色体的位置有所不同;伞柱开口箭(T. fungilliformis)为2n=2x=38=18m 2sm 12st 6t。前述5个种的核型由一型染色体组成,而伞柱开口箭的核型由二型染色体组成。开口箭属和蜘蛛抱蛋属(Aspisdistra)是亲缘关系接近的两个属,伞柱开口箭是开口箭属和蜘蛛抱蛋属之间的一个过渡类群。     

醉鱼草属四个种的核型分析

报道了醉鱼草属（Btuldleja）4个种的染色体核型。云南醉鱼草（B.yunnanensis）的核型公式为2n=2x=38=22m＋16sm,皱叶醉鱼草（B．crispa）为2n=2x=38=26m＋10sm＋2st,密蒙花（B．officinalis）为2n=2x=38=20m＋16sm＋2st,口本醉鱼草（B．japonica）为2n=2x=38=20m＋16sm＋2st。日本醉鱼草的核型为2B型,其它3个种的核型为2A型。根据核型分析结果,结合形态学特征和已有的细胞学资料,初步讨论了醉鱼草组（Sect．Neemda）两个系（Series）可能的演化关系。     

Karyotype of Four Species in Buddleja ( Loganiaceae) *

The chromosome numbers and karyotypes of the 4 species in genus Buddleja were reported. The karyotype formulas are 2n= 2x= 38= 22m+ 16sm ( B1 yunnanensis) , 2n= 2x= 38= 26m+ 10sm+ 2st ( B1 crispa) , 2n= 2x= 38= 20m+ 16sm + 2st ( B1 off icinalis ) , and 2n= 2x= 38= 20m+ 16sm+ 2st ( B1japonica) . Karyotype of B1japonica belongs to Stebbins. s 2B type and other 3 species belong to Stebbins. s 2A type. Based on the cytological data ( karyotypes and the recorded chromosome numbers) and the species morphologies, the evolution trend of the two series in Sect1Neemda was briefly discussed.