国产五种菊属植物的核型研究

本文对国产5种菊属植物的核型进行了研究,结果为:D. indicum 2n=2x=18=16m 2st,2n=4x=36=28m 6sm 2st;D. lavandulifolium 2n=2x=18=14m 4sm,2n=4x=36=28m 6sm 2st;D. lavandulifolium var.seticuspe 2n=2x=18=12m 6sm;D. chanetii 2n=4x=36=20m 14sm 2st,2n=6x=54=38m 14sm 2st;D. potentilloides2n=2x=18=14m 2sm 2st;D. vestitum 2n=6x=54=38m 16sm.核型分析的结果表明,本文所研究类群中出现的多倍体多为异源多倍体;根据对核型资料、形态特征及地理分布特点的综合分析,作者认为多倍化是菊属野生种进行的主要途径。     

Karyotypes of metaphase chromosomes in diploid populations of Dendranthema zawadskii and related species (Asteraceae) from Korea: diversity and evolutionary implications

Although the Dendranthema zawadskii complex has been known to comprise a series of polyploids (4x, 6x, 8x), we found diploid individuals (with 2 n=18) to occur in four populations of D. zawadskii var. latilobum in the southern region of Korea. Karyotypes of metaphase chromosomes were diverse because numbers of metacentric, submetacentric, and acrocentric chromosomes differ even within a population. A total of 17 karyotypes were found in 31 diploid individuals collected from the four populations. The karyotypes were also diverse in the presence or absence of chromosomes with a secondary constriction on a short or long arm and, if present, in the number of such chromosomes. They were further diverse in the presence or absence of non-homologous chromosome(s), the presence or absence of a chromosome with a satellite, and, if present, how many and where satellites are present. Almost the same pattern of diversity was found in diploid individuals (with 2 n=18) of D. boreale and D. indicum as well, irrespective of whether they occur together with D. zawadskii var. latilobum or not. Structural features of chromosomes in the variously different karyotypes suggest that reciprocal translocation and the hybridization between individuals with different karyotypes had repeatedly occurred not only in D. zawadskii var. latilobum, but also in D. boreale and D. indicum. Morphologically intermediate individuals between D. zawadskii var. latilobum and D. indicum suggests that the hybridization occur with different species as well.     

柑桔类的细胞分类学研究 Ⅰ.柑桔属30个分类群的核型及进化

作者研究了柑桔属30个分类群的核型及进化。结果表明:染色体数目为2n=2x=18,属小染色体植物,核型由中部着丝粒染色体(m)和近中部着丝粒染色体(sm)组成,具2—4个连接于短臂上的随体,一些分类群的部分同源染色体上存在长度和臂比值不同程度的杂合现象,核型均属2A型。比较随体及与之相连短臂,其随体分为大随体(LS)中随体(MS)和小随体(SS)三类,随体的多样性可作为探讨该属物种的起源、系统演化的一个遗传标志。作者赞同把柚(Citrus grandis)作为柑桔属的一个基本种,而宽皮柑桔(C.reticulata)核型变异较大,还待进一步分析;推测红黎檬(C.limonia)、葡萄柚(C.paradisi)、甜橙(C.sinensis)、酸橙(C.aurantium)、香园(C.wilsonii)、三宝柑(C.sulcata)、部分宽皮柑桔(C.reticulata)为杂种起源。该属核型由不对称向对称进化是与形态及孢粉的进化趋势一致的。     

东北地区菊属植物叶表面结构的研究

本文利用光镜和扫描电镜研究了中国东北菊尼（Ｄｅｎｄｒａｎｔｈｅｍａ）９种和变种（野菊;葫芦岛野菊;楔叶菊;小红菊;甘菊;甘菊甘野菊;紫花野菊;细叶菊和小山菊）的叶表面特征。这些类群在表皮细胞,气孔复体和毛状体方面等存在着一些差异。依据这些特征讨论了一些类群的关系并尝试性地依据这些特征编制了这些类群检索表。     

Leaf anatomy of a rheophyte,Dendranthema yoshinaganthum (Asteraceae), and of hybrids between D. yoshinaganthumand a closely related non-rheophyte,D. indicum

The rheophyte Dendranthema yoshinaganthum(Makino ex Kitam.) Kitam. is endemic to a region along the Naka River in Shikoku, Japan. Resembling other rheophytes that have adapted to environments along rivers, D. yoshinaganthumhas narrow leaves. In the native habitat of D. yoshinaganthumin Tokushima, Japan, natural hybridization with Dendranthema indicum (L.) Des Moul. has resulted in a species complex with conspicuous variation in leaf shape and, in particular, in leaf width. In this study, D. yoshinaganthum and hybrids with natural variation in leaf shape were cultivated under identical conditions and the anatomy of their leaves was examined. Variation in leaf width in the species complex was attributable, for the most part, to variation in the number of cells per leaf lamina and also, to some extent, to variation in cell size. This is the first report of natural variation in leaf width that is attributable to variation in both the size and the number of leaf cells.     

柑桔类的细胞分类学研究——Ⅰ.柑桔属30个分类群的核型及进化

作者研究了柑桔属30个分类群的核型及进化.结果表明:染色体数目为2ⁿ=2x=18,属小染色体植物,核型由中部着丝粒染色体(m)和近中部着丝粒染色体(sm)组成,具2—4个连接于短臂上的随体,一些分类群的部分同源染色体上存在长度和臂比值不同程度的杂合现象,核型均属2A型.比较随体及与之相连短臂,其随体分为大随体(LS)中随体(MS)和小随体(SS)三类,随体的多样性可作为探讨该属物种的起源、系统演化的一个遗传标志.作者赞同把柚(Citrus grandis)作为柑桔属的一个基本种,而宽皮柑桔(C.reticulata)核型变异较大,还待进一步分析;推测红黎檬(C.limonia)、葡萄柚(C.paradisi)、甜橙(C.sinensis)、酸橙(C.aurantium)、香园(C.wilsonii)、三宝柑(C.sulcata)、部分宽皮柑桔(C.reticulata)为杂种起源.该属核型由不对称向对称进化是与形态及孢粉的进化趋势一致的.     

The importance of phylogeny and ecology in microgeographical variation in the morphology of four Canarian species of Aeonium (Crassulaceae)

The relative importance of natural selection in the diversification of organisms can be assessed indirectly using matrix correspondence. The present study determines the environmental and genetic correlates of microgeographical variation in the growth form, leaf form and flower morphology in populations of four Aeonium species from section Leuconium using partial regression methods. The phylogeny of the four species and the other 12 species in the section was deduced from amplified fragment length polymorphism (AFLP). Pubescence of floral organs and flower size correlate with the phylogeny while traits related to growth form, leaf form, flower construction and inflorescence size correlate with ecological factors. The variation in the latter four traits may therefore reflect selection by current ecological conditions while variation in pubescence and flower size may reflect historical events like neutral mutations, founder events and drift. Additionally, the morphological analyses revealed a large amount of variation in all traits within populations. This suggests a possible influence of microhabitat on the variation in morphology of Aeonium in the Canary Islands.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 76 , 521–533.     

芝麻染色体核型及似近系数分析

芝麻（Sesamum indicum L.）是世界上最古老的油料作物之一,在植物进化中具有重要地位。以8个二倍体栽培种、4个四倍体栽培种以及2个野生种S.radiatum Schum ＆ Thonn和S.schinzianum Asch.为材料,比较分析了芝麻不同种的核型特征。结果表明：栽培种与野生种的核型及结构具有明显的差异,栽培种的着丝点类型有m、sm和st,臂比均值（AAR）为2.11–2.25,核型不对称系数（AKC）为66.05%–66.99%,核型分2B、3A和3B三类;野生种S.radiatum和S.schinzianum仅有M和m两种着丝点类型,AAR值分别为1.09和1.08,AKC为52.12%和51.68%,核型分1B和1A两类。核型聚类结果表明,野生种与栽培种的似近系数范围介于0.027–0.107之间,亲缘关系较远;与地理来源相比,种皮颜色能够显示不同种间的进化地位,推测芝麻进化方向为野生种→栽培种黑芝麻→栽培种白芝麻。     

Variations in C-banding patterns and DNA values in two scorpion-fishes (Scorpaena porcus andS. notata,Teleostei)

The karyotypes of two morphologically similar species,Scorpaena porcus andS. notata, were analyzed by means of silver staining and C-banding techniques. The variation in their DNA values (S. porcus = 0.92 pg andS. notata = 0.56 pg) is positively related to the variation in chromosome number and to the amount of C-banded heterochromatin. Only one chromosome pair shows the nucleolus organizer regions, and this has similar characteristics in both species. These data are discussed in terms of the karyotypical evolution of the genusScorpaena.     

The effects of foliar pubescence and nutrient enrichment on arthropod communities of Metrosideros polymorpha (Myrtaceae)

Abstract.  1. Nutrient resource availability and host-plant foliar pubescence both influence arthropod food webs, but multifactor studies are needed to understand their interdependence and relative importance. Arthropods were sampled by clipping foliage from Metrosideros polymorpha (Myrtaceae) trees of pubescent, glabrous, and intermediate leaf forms on fertilised and unfertilised plots.
2. Fertilisation decreased leaf mass per area (LMA) but did not change the relative mass of pubescence within leaf morphological classes.
3. Fertilisation increased densities of individuals in four taxonomic orders, densities of individuals and species of all trophic levels, and the biomass of Collembola and Homoptera. Herbivore relative diversity (Shannon H ') also increased with fertilisation, but detritivore diversity declined due to increasing dominance of Salina celebensis (Schaeffer) (Collembola).
4. Detritivore density, driven again by S. celebensis , increased with decreasing leaf pubescence, but Heteroptera and Acari were most abundant on the intermediate pubescence class, and Psocoptera density and biomass increased with increasing pubescence. Trophic-level species density did not change with leaf morphological class, but relative diversity of all arthropods and of detritivores increased with increasing pubescence.
5. Both resource availability and leaf pubescence affected Metrosideros arthropod communities. However, the pervasive positive influence of fertilisation did not translate to compositional shifts, and there were no interactions with leaf morphological class. In contrast, the effects of leaf pubescence on arthropod density, biomass, and diversity were more restricted taxonomically, and non-parametric manova and redundancy analyses demonstrated significant differentiation in community composition on the pubescent morphology.     

粗根韭的核型分化研究

对葱属粗根韭的3个地方居群的核型分析结果表明,3个居群的核型表现出很大的差异。西藏 达孜居群为2n=2x=20=4m+10sm+2t(2SAT)+4T;四川乡城居群为2n=2x=20=10sm+6t (2SAT)+4T;四川理县居群为2n=2x=20=6m+1Osm+2t(2SAT)+2T。虽然它们之间在核型上存 在差异,但除达孜居群的植株较矮小外,3个居群的植物在形态上却非常一致。理县居群的核型被认为 是原始类型,由它通过染色体结构变异,分别演化出更不对称的达孜居群和乡城居群。葱属中,目前只 发现4个种的染色体基数为10,除本种外其余3种分别是A．decipiens Fisch．;A．kujukense Vved．和 A．chelotum Wendelbo。根据这4个种的核型特征和分布格局,基数10可能有不同的起源,至少粗根韭 的起源与其余3种不同,而且起源最晚。粗根韭的核型特征及它与染色体基数为11的宽叶韭A．hook- eri Thwaites在核型上的相似性,表明它们很可能共同起源于基数为10但现已绝灭的祖先种。此外,还探讨了该祖先种的起源问题。     

国产黄连属植物的染色体核型分析

中国黄连属6种1变种分属叶掌状三全裂和叶掌状五全裂2个类群,前者包括三角叶黄连、峨眉黄连、云南黄连、黄连和其变种短萼黄连;而分布于滇东南的五裂黄连和产于台湾的五叶黄连则归于后者。采用根尖压片法和卡宝品红染色法,对除五叶黄连外的中国黄连属5种1变种,以及日本黄连进行染色体核型比较分析,从细胞学角度为探讨中国黄连属植物的系统分类提供新的线索和证据。结果表明:(1)五裂黄连(2n=2x=18=2M+16m)、短萼黄连(2n=2x=18=8m+10sm)和日本黄连(2n=2x=18=12m+6sm)的染色体数目和核型均为首次报道。(2)7个材料的染色体基数均为9,除三角叶黄连为三倍体外,其余均为二倍体。(3)叶为掌状三全裂的二倍体种核型一致,为2A型,染色体类型以及不对称系数均很相似;叶为掌状五全裂的五裂黄连与五叶黄连的核型更接近,为1A型,核型特征的共性表明了这2个类群的自然属性。(4)三倍体三角叶黄连的不对称程度较高,核型为3A型,其染色体大小与峨眉黄连最接近。(5)根据核型不对称程度和染色体大小,结合地理分布,推测叶掌状五全裂种为本属的原始类群。     

Introgressive hybridization in two southern California species of Rhus (Anacardiaceae)

Five populations ofRhus integrifolia andR. ovata were studied and, based upon morphological characteristics and pollen viability, a number of putative hybrids were found in those areas where the two species are sympatric. Diagnostic characteristics most useful for distinguishing the species and their hybrids are leaf morphology, sepal pubescence, petiole length, and petal size. Introgression was evident in at least three populations, which suggested that hybridization between the two species is an ancient phenomenon. Evolutionarily, hybridization between the two taxa has probably been of little consequence.     

Cytogenetic and phytochemical investigations in hybrids of MacaronesianDryopteris (Pteridophyta: Aspidiaceae)

The cytology and phloroglucinol composition of wild and synthesized hybrids of MacaronesianDryopteris species have been examined. Both cytological and chemical evidence suggest that the tetraploidD. guanchica has arisen from the diploid speciesD. aemula andD. maderensis by hybridization and chromosome doubling. However, the formation of the characteristic fully aromatic compounds inD. aemula appears to be suppressed in most of the hybrids involving this species, and inD. guanchica.     

A new species of the Brazilian genus Chresta (Asteraceae, Vernonieae) from Bahia

A new species of the genus Chresta Vell. ex DC. (Vernonieae, Asteraceae) from the Brazilian state of Bahia is described and illustrated. The new species resembles Chresta pinnatifida (Philipson) H.Rob. but differs in having solitary glomerules, leaf bases clasping the stem and 35–40 capitula per glomerule. It can be distinguished from Chresta harleyii and Chresta martii , the other two species of the genus with pinnately lobed leaves, by the type of pubescence, leaf blade bases and florets number. In addition, a key to distinguish all the species of the genus is presented. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 587–590.     

Molecular evidence for multiple polyploidization and lineage recombination in the Chrysanthemum indicum polyploid complex (Asteraceae)

The Chrysanthemum indicum polyploid complex comprises morphologically differentiated diploids, tetraploids and hybrids between C. indicum and C. lavandulifolium. The relationships between species and cytotypes within this complex remain poorly understood. Random amplified polymorphic DNAs (RAPDs), intersimple sequence repeats (ISSRs) and chloroplast SSR markers were used to elucidate the genetic diversity and relationships of the C. indicum polyploid complex. Molecular analysis of three diploid and nine tetraploid populations provided strong evidence for recurrent origins and lineage recombination in the C. indicum polyploid complex. The high similarity in molecular marker profiles and cpDNA haplotypes between the diploids and tetraploids distributed in the Shen-Nong-Jia Mountain area of China suggested an autopolyploid origin of the tetraploids, while the tetraploids from other populations may have originated via allopolyploidization. Lineage recombination was revealed by the extensive sharing of chloroplast haplotypes and genetic markers among the tetraploid populations with different origins. Multiple differentiation and hybridization/polyploidization cycles have led to an evolutionary reticulation in the C. indicum polyploid complex, and resulted in the difficulties in systematic classification.     

Chromosome numbers and karyotypic evolution of Caraboidea

The chromosome numbers of 136 species of the Spanish caraboid fauna were studied. The most frequent karyotypes are 2n=37 (54 species) and 2n=24 (23 species), and the chromosome number ranges from 2n=21 to 2n=69, of which 2n=69 is the highest diploid number hitherto found among the Coleoptera. It is proposed that 2n=37 is the ancestral karyotype of the division Caraboidea and the suborder Adephaga as opposed to that of the suborder Polyphaga, 2n=20. Karyotypic evolution has led to increases and decreases of this number, both tendencies having taken place in four genera. Species of ten genera show a neo-XY bivalent due to an X-autosome fusion. The thirty-three chromosome numbers of Caraboidea reveal that these Coleoptera have a remarkable karyotypical heterogeneity.     

葱属宽叶组植物细胞分类学研究

百合科Liliaceae葱属Allium的宽叶组Sect．Anguinum包括5种3变种。通过对该组的5种1变 种的23个地方居群的研究,得出以下结果。(1)宽叶组植物的染色体基数为8,核型类型一致,为2A 型,染色体类型以及不对称系数都很相似。核型特征的共性表明该组是一个自然的分类群。(2)虽然 总体上组内的核型表现出较大的相似性,但在种间和种内各居群间也存在一定的差异。主要表现为：有 的种内存在染色体的倍性变化;B染色体的有无以及数目和形态,在种内不同居群间存在变化;随体染 色体上衔接随体的有无,在种间及种内都表现出多态性。(3)三倍体卵叶韭Allium ovalifolium高度不 育,靠新产生的地下走茎进行无性繁殖,以此扩大居群。(4)根据善葱A．victorialis分布区广而地史相 对古老的分布格局,推测它为本组的原始类群。它通过地理的(渐进的)物种形成方式,逐步演化形成现 在的各个分类群。(5)根据该组植物的分布格局和演化过程,提出我国横断山区至秦岭一带为本组植物的现代分布中心和分化中心。     

Mapping quantitative trait loci associated with leaf and stem pubescence in cotton

Leaf pubescence in cotton have a potential for insect pest management. Varying degrees of leaf trichome density in Gossypium species and cultivars have been associated to a series of five genes, referred to as t(1)-t(5). We used two segregating interspecific G. hirsutum x G. barbadense backcross populations developed in our laboratory to assess qualitatively and quantitatively leaf and stem pubescence. QTL analyses were performed using simple and composite interval mapping. Based on both types of measurements and under both types of QTL analyses, nine QTLs met permutation-based thresholds. The nine QTLs mapped to four different chromosome regions. Highest LOD values corresponded to the QTLs detected on c6 (four colocalized QTLs) and on D03 (two QTLs) for which the higher pubescence in the progeny derived from the pubescent G. hirsutum parent alleles. Conversely, on c17 (one QTL) and A01 (two QTLs), the G. hirsutum parental alleles affected negatively pubescence. These results combined with another published study confirm (1) the location in a center region of chromosome 6 of the t(1) locus as a major locus/gene determining leaf pubescence, and (2) additional genes located on seven additional chromosomes have been shown to impart trichome density either positively or negatively. The existence of a high density of PCR-based loci in most of the regions identified as harboring leaf pubescence QTLs, particularly that on chromosome 6, will facilitate future efforts for map-based cloning.     

Past climatic fluctuations are associated with morphological differentiation in the cloud forest endemic tree <Emphasis Type="Italic">Ocotea psychotrioides</Emphasis> (Lauraceae)

Pleistocene glacial periods have had a major influence on the geographical patterns of genetic structure of species in tropical montane regions. However, their effect on morphological differentiation among populations of cloud forest plants remains virtually unexplored. Here, we address this question by testing whether geographical patterns of morphological variation in Ocotea psychotrioides can be explained by the intensity of climate change occurring during 130,000 years. For this, we measured vegetative and reproductive traits for 96 individuals from 36 localities registered across the species’ distribution range. Species distribution models and multivariate statistics were used to investigate geographical patterns of morphological variation and test their association with current and past climatic conditions. Leaf size and pubescence in O. psychotrioides showed a latitudinal pattern of clinal variation that does not fit the geographical gradient of increasing leaf size towards lower latitudes observed globally among plants. Instead, the observed clinal variation conforms to a pattern of increasing leaf size towards higher latitudes. However, our analyses showed weak to non-significant association between morphology and current climate. Interestingly, our analyses showed that predicted shifts in the distribution range of O. psychotrioides during the last 130,000 years were accompanied by significant changes in climatic conditions, particularly temperature seasonality and precipitation. Accordingly, climatic instability showed a better fit to the observed patterns of leaf size and pubescence variation than current climate conditions. These results suggest that climatic instability during the Pleistocene glacial periods might play a key role in promoting morphological differentiation among populations of cloud forest plants.