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1.
A molecular phylogenetic study of Plantago L. (Plantaginaceae) analysed nucleotide variation in the internal transcribed spacers (ITS) of nuclear ribosomal and plastid trnL-F regions. Included are 57 Plantago species, with two Aragoa species as the ingroup and three Veronica species as the outgroup. Phylogenetic analysis using maximum parsimony identified five major clades, corresponding to the taxonomic groups Plantago subgenera Plantago, Coronopus, Psyllium, Littorella and Bougueria . Aragoa is sister to genus Plantago . Plantago subgenus Littorella is sister to the other subgenera of Plantago . The results are in general correlated with a morphological phylogenetic study and iridoid glucoside patterns, but Plantago subgenus Albicans is paraphyletic and should be included in Plantago subgenus Psyllium sensu lato to obtain a monophyletic clade with six sections. Plantago section Hymenopsyllium is more closely related to section Gnaphaloides than to section Albicans . Plantago subgenus Bougueria is sister to subgenus Psyllium s.l. section Coronopus in Plantago subgenus Coronopus is subdivided in two series. Only some of the sections can be resolved into series. DNA variation within genus Plantago is high, a result that would not have been predicted on the basis of morphology, which is relatively stereotyped. If we calibrate a molecular clock based on the divergence of P. stauntoni , endemic to New Amsterdam in the southern Indian Ocean, we calculate the time of the split between Plantago and Aragoa to be 7.1 million years ago, which is congruent with the fossil record.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 323–338.  相似文献   

2.
This paper reports a novel microwave initiated method for synthesis of polyacrylamide grafted Psyllium (Psy-g-PAM). Psyllium was modified through grafting of polyacrylamide (PAM) chains on it using microwave radiations only, in absence of any other free radical initiator. The grafting was confirmed by intrinsic viscosity study and characterization techniques like FTIR spectroscopy, elemental analysis (C, H, N, O and S) and SEM morphology study. Further, the flocculation efficacy of the synthesized graft copolymers was studied in kaolin and coal fine suspension through standard 'Jar test' procedure.  相似文献   

3.
用SSR分子标记研究大豆属种间亲缘进化关系   总被引:39,自引:2,他引:37  
利用SSR标记技术对大豆属11个种37份材料的遗传多样性进行分析,不同位点在种间的等位基因数为6-29,平均生个位点15.9个等位基因,Soja亚属的等位基因数是Glycine亚属的71.5%,并且Glycine亚属种间指纹 谱的差异大于Soja亚属种间的指纹图谱,SSR等位基因的主成分分析结果表明,大豆属中的Glycine亚属和Soja亚属的分类界限是比较明确的,利用第一主成分和第二主成分可较明显地区分开Glycine 亚属的分类界限是比较明显的,利用第一主成分和第二主成分可较明显地区分开Glycine亚属和Soja亚属,通过UPGMA方法构建了大豆属11个种的遗传进化关系,Soja亚属中G.max,G.soja和G.gracilis3个种在系统分化树上界限是比较明显的,由此看来这3个种是独立存在的。  相似文献   

4.
The anatomy of the leaf epidermis of 49 of the approximately 65 African species of Combretum subgenus Cacoucia is described. This is discussed in relation to the taxonomy of the subgenus, particularly its sectional classification. Of the 17 sections which have been describrd, Campylogyne is now referred to the genus Quisqualis, Argyrotricha is referred to Combretum subgenus Combretum , and Angolensia, Grandiflora, Mweroensia, Parvula and Trichopetala are included with other sections. Combretum grandidieri is referred to the genus Calopyxis . In general the leaf epidermis of speries of subgenus Cacoucia is of far lower taxonomic value than in subgenus Combretum .  相似文献   

5.
The ndhF sequences of 99 taxa, representing all sections in extant Magnoliaceae, were analyzed to address phylogenetic questions in the family. Magnolia macrophylla and M. dealbata, North American species of Magnolia section Rytidospermum, are placed at the base in the subfamily Magnolioideae although its supporting value is low. In the remaining taxa, several distinctive lineages are recognized: (1) Magnolia, the biggest genus in the family, is not monophyletic; (2) Michelia, including section Maingola of Magnolia subgenus Magnolia, is closely related with Elmerrillia and sections Alcimandra and Aromadendron of Magnolia subgenus Magnolia; (3) the associates of Michelia are grouped with Magnolia subgenus Yulania and section Gynopodium of Magnolia subgenus Magnolia; (4) Pachylarnax forms a clade with sections Manglietiastrum and Gynopodium of Magnolia; (5) a well-supported Manglietia clade is recognized; (6) Caribbean species of section Theorhodon of Magnolia subgenus Magnolia, which are section Splendentes sensu Vázquez-Garcia, are closely allied with New World members of Magnolia subgenus Talauma; and (7) section Rytidospermum of Magnolia subgenus Magnolia and subgenus Talauma are polyphyletic. The separated clades in the molecular tree are considerably different from traditional taxonomic dispositions in the family. The molecular data strongly suggest that a taxonomic realignment of infrafamilial delimitations and compositions should be considered.  相似文献   

6.
7.
The geographical distribution maps of the subgenus Pogonophace (Fabaceae: Astragalus) in China were designed and drawn using GIS cartographic technique. The species of the subgenus and county of China were treated as the basic composition units in the GIS cartographic technique. Most of the distribution maps were shown in spots. The distribution pattern of the subgenus illustrates that it is a peculiar group to adapt the cold alpine environment and distribute mainly in Hengduan Mountains and Himalayas. According to the geographical distribution maps and some statistic analyses, Hengduan Mountains region is suggested to be the distribution center, differentiation center and endemic center of the subgenus. Some vicariance traces at levels of the species or sections are very interesting among the distribution patterns of the subgenus and shown clearly in the maps.  相似文献   

8.
用GIS技术设计和绘制了豆科黄耆属(Astragalus L.)簇毛黄耆亚属在中中的地理分布图。以种类和县级分面为基本构图单元。分布图形均呈斑块状。分布式样提示出亚属是一个集中分布在横断山和喜马拉雅,适应于高寒山地的特化类群。根据地理公布直观图及有关统计分析,认为横断山是这个亚属的分布中心、分化中心和特有中心。公布式样和直观图还揭示出一些种之间、组之间有趣的替代现象。  相似文献   

9.
The origins and times of divergence of the speciose Hawaiian Drosophilidae are examined using mtDNA sequences. The Hawaiian Drosophilidae are resolved as the sister group to the subgenus Drosophila. No one member of the subgenus Drosophila could be determined to be more closely related to the Hawaiian Drosophilidae than could any other. This result suggests that the Hawaiian Drosophilidae arose before the diversification of the subgenus Drosophila and after the divergence of the subgenus Sophophora. In light of fossil evidence, this phylogenetic scenario suggests that the Hawaiian Drosophilidae lineages are no younger than 30 Myr.  相似文献   

10.
Snubnose darters comprise one of the largest subgenera of the percid genus Etheostoma. Many species are described based on differences in male breeding coloration. Few morphological synapomorphies have been proposed for the subgenus and their relatives, making it difficult to delineate monophyletic clades. The phylogenetic relationships of the 20 snubnose darter species of the subgenus Ulocentra and 11 members of its proposed sister subgenus Etheostoma were investigated with partial mitochondrial DNA sequences including 1033 bp encompassing the entire mitochondrial control region, the tRNA-Phe gene, and part of the 12S rRNA gene. Two hypotheses on the relationship and monophyly of the two subgenera were evaluated. Both maximum-parsimony and neighbor-joining analyses supported monophyly of the subgenus Ulocentra and resolved some species-level relationships. The banded darter, E. zonale, and its sister taxon, E. lynceum, were not closely related to the snubnose darters and appear to be diverged from the other members of the subgenus Etheostoma, fitting their former distinction as the recognized subgenus Nanostoma. The sister group to Ulocentra appears to be a restricted species assemblage within the subgenus Etheostoma containing E. blennioides, E. rupestre, E. blennius, and the E. thalassinum species group. The placement of the harlequin darter, E. histrio, is problematic, and it may represent a basal member of Ulocentra or of the restricted subgenus Etheostoma. Despite recent estimates of divergence times between nominal Ulocentra taxa, each species exhibits its own unique set of mtDNA haplotypes, providing no direct evidence for current genetic exchange between species. The nominal taxa of snubnose darters thus appear to be evolving independently from each other and therefore constitute valid species under the Phylogenetic Species Concept.  相似文献   

11.
蚜属轭蚜亚属的研究及一新种记述(同翅目:蚜科)   总被引:1,自引:1,他引:0  
本文记述世界范围蚜属的轭蚜亚属11种,其中包括1新种,地肤轭蚜Aphis (Zyxaphis)kochiae Zhang et Zhang,sp.nov.。给出分种检索表。该亚属为中国新纪录。模式标本存放在中国科学院动物研究所标本馆。地肤phis(Zyxaphis)kochiae Zhang et Zhang,sp.nov.,(图1~6)正模,无翅孤雌,No.Y7701-2-其余同正模。中与A.(  相似文献   

12.
This study examined the interspecific amplification of nuclear microsatellite loci developed mainly for eucalypts in the subgenus Symphyomyrtus across five species within the second most speciose subgenus, subgenus Eucalyptus. A set of eight to 10 loci, depending on taxon, have been identified that are highly variable and easily scored. The successful transfer of microsatellite loci to these eucalypt species sidesteps the expensive and time-consuming development of species-specific microsatellite libraries. This primer set will enable the examination and cross-species comparison of the genetic resources of commercially and ecologically important members of the subgenus Eucalyptus.  相似文献   

13.
Three main types of seed-discharge in Geranium are made the basis of its division into subgenera: Geranium subgenus Geranium , with a ballistic expulsion of the seed from the mericarp, termed 'seed-ejection'; Geranium subgenus Robertium , with forcible discharge of the mericarp with the seed in it, separately from the awn, termed 'carpel-projection', and Geranium subgenus Erodioideae , with the seed-containing mericarp being thrown off with the attached awn, which becomes helically coiled, called the 'Erodium-type'. Variants of the seed-ejecting type permit the division of Geranium subgenus Geranium into three sections. Other criteria are used to divide Geranium subgenus Robertium into eight sections and Geranium subgenus Erodioideae into two. Species are fully enumerated except for Geranium section Geranium , which comprises the bulk of the genus, and for which some tentative subgroups are given in an Appendix. Diversity of fruit-type in Geranium is greatest in the Mediterranean Region. Characters of the fruit in other genera of Geraniaceae are surveyed. Geographical distributions, chromosome numbers, pollen morphology and phytochemistry are reviewed. It is suggested that Erodium-type fruit discharge, shared with the four remaining genera of the family, is primitive, and that carpel-projection and seed-ejection arose from it separately, the latter probably more than once. The very large, mainly perennial, Geranium subgenus Geranium is contrasted with Geranium subgenus Robertium , half of which is hapaxanthic, and which occupies marginal habitats and shows greater morphological and chromosomal variation despite its being only one tenth the size. Geranium subgenus Erodioideae is smaller still and probably relictual.  相似文献   

14.
Phylogenetic analyses of 46 species of Iris, representing all subgenera and all sections except Regelia, Brevituba, and Monolepis, utilized matK gene and trnK intron sequence data. Sequence data show that Iris is paraphyletic because Belamcanda chinensis is resolved within the genus. The two largest subgenera, Iris and Limniris, are both resolved as polyphyletic. With the removal of section Hexapogon, subgenus Iris is weakly supported as monophyletic. Relationships within subgenus Limniris are more complex with the subgenus as currently circumscribed representing eight independent origins among the species included in this study. Several potential monophyletic groups are identified including subgenus Scorpiris, series Spuria (subgenus Limniris section Limniris), and a clade of section Limniris species from North America and Asia.  相似文献   

15.
The subgenus Semirodus Dlabola, 1987 of the genus Mycterodus Spinola, 1839 with all known species are redescribed. Four new species of the subgenus from Greece and West Turkey are described. A key to the species of the subgenus is proposed.  相似文献   

16.
Incarvillea is a herbaceous and temperate member of Bignoniaceae, previously divided into four subgenera, Niedzwedzkia, Amphicome, Incarvillea, and Pteroscleris. Niedzwedzkia and Amphicome have in the past been treated as independent genera. Different relationships have been proposed for the four subgenera. Here, maximum parsimony analysis using ITS and trnL-F sequences resulted in similar trees and showed that the genus is monophyletic. Analysis of the combined data resulted in a single tree with five major clades highly supported and well resolved. The relationships of the five major clades are (subgenus Niedzwedzkia (Incarvillea olgae (subgenus Amphicome (subgenus Incarvillea, subgenus Pteroscleris)))). All four subgenera are well supported for monophyly, with the exception of subgenus Incarvillea, represented here by I. sinensis and I. olgae. Incarvillea olgae is not closely related to I. sinensis, a conclusion supported by morphology. The two basal monotypic subgenera are found in Central Asia. The most species-rich subgenus, Pteroscleris, has 10 species in the Himalaya-Hengduan Mountains and may have dispersed early from central Asia to eastern Asia. Short branch lengths on the molecular trees within Pteroscleris suggest a recent and rapid radiation of this rosette-forming subgenus, perhaps connected with the uplift of the Himalaya-Hengduan massif.  相似文献   

17.
The subgenus Chimarrita of the genus Chimarra is erected to include three described species, formerly placed in the subgenus Chimarra , and fifteen new species, all with distributions in the Greater Antilles or South America. A phylogeny for the species in the subgenus, and characters supporting monophyly of the subgenus Chimarrita , are proposed, as well as evidence for the monophyly of the subgenera Chimarra and Curgia . Keys are provided for the males and known females of the subgenus. Described species transferred to this subgenus are Chimarra simpliciforma Flint, Chimarra rosalesi Flint, and Chimarra maldonadoi Flint. Chimarra simpliciforma is designated the type species for the subgenus. New species in Chimarra ( Chimarrita ) described in this paper include: Chimarra akantha (Brazil), C . camella (Brazil), C . camura (Brazil), C . chela (Venezuela), C . forcipata (Venezuela), C . heligma (Brazil), C . heppneri (Peru), C . kontilos (Brazil), C . majuscula (Brazil), C . merengue (Dominican Republic), C . neblina (Venezuela), C . prolata (Ecuador), C . pusilla (Venezuela), C . tortuosa (Brazil), and C . xingu (Brazil).  相似文献   

18.
国产黄耆属簇毛黄耆亚属花粉形态及其系统学意义   总被引:2,自引:0,他引:2  
观察了国产黄耆属簇毛黄耆亚属6组12种植物的花粉形态。这些花粉的外壁表面纹饰可分为网状纹饰,穿孔或小沟渠状,以及穴网状纹饰3种类型。所有种类都具三孔沟的萌发孔,根据内孔明显与否可分为两类。虽然萌发孔类型与分组并没有严格的对应关系,但综合一些花粉特征,仍然发现6个组间花粉形态差异较为明显,与一般的形态差异有一定的对应性。特别是Sect.Robusti比较特殊,根据花粉大小等特征,推测它和Sect.Phyllolobium等有可能是本亚属的原始类群。Sect.Sesbanella的两个近缘种Astragalus heydei和A.hendersonii,花粉形态却很有区别。Sect.Bibacteola种类较多,有24种,花粉形态呈多样性。总之,花粉形态在簇毛亚属中具有一定的系统学意义。  相似文献   

19.
Phylogeny and Classification of Prunus sensu lato (Rosaceae)   总被引:3,自引:0,他引:3  
The classification of the economically important genus Prunus L. sensu lato (s.L) is controversial due to the high levels of convergent or the parallel evolution of morphological characters. In the present study, phylogenetic analyses of fifteen main segregates of Prunus s.I. represented by eighty-four species were conducted with maximum parsimony and Bayesian approaches using twelve chloroplast regions (atpB- rbcL, matK, ndhF, psbA-trnH, rbcL, rpL 16, rpoC1, rps16, trnS-G, trnL, trnL-F and ycfl) and three nuclear genes (ITS, s6pdh and Sbel) to explore their infrageneric used to develop a new, phylogeny-based classification relationships. The results of these analyses were of Prunus s.I. Our phylogenetic reconstructions resolved three main clades of Prunus s.I. with strong supports. We adopted a broad-sensed genus, Prunus, and recognised three subgenera corresponding to the three main clades: subgenus Padus, subgenus Cerasus and subgenus Prunus. Seven sections of subgenus Prunus were recognised. The dwarf cherries, which were previously assigned to subgenus Cerasus, were included in this subgenus Prunus. One new section name, Prunus L. subgenus Prunus section Persicae (T. T. yu & L. T. Lu) S. L. Zhou and one new species name, Prunus tianshanica (Pojarkov) S. Shi, were proposed.  相似文献   

20.
Klich MA  Cary JW  Beltz SB  Bennett CA 《Mycologia》2003,95(6):1252-1260
Aspergillus ochraceoroseus produces the yellow-gold conidia and other characteristics of Aspergillus subgenus Circumdati section Circumdati. However, this species produces aflatoxin, a secondary metabolite characteristic of some members of subgenus Circumdati section Flavi and sterigmatocystin, a related secondary metabolite usually associated with subgenus Nidulantes sections Nidulantes and Versicolores, as well as members of several other genera. Our morphological data support the placement of A. ochraceoroseus in subgenus Circumdati. Sequence data from A. ochraceoroseus aflatoxin and sterigmatocystin genes aflR and nor-1/stcE, as well as 5.8S ITS and beta tubulin genes, were compared to those of aspergilli in sections Circumdati, Flavi, Nidulantes and Versicolores. In the sequence comparisons, A. ochraceoroseus was related more closely to the species in subgenus Nidulantes than to species from subgenus Circumdati.  相似文献   

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