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1.
Sophora tomentosa , the type species of the genus Sophora , is shown by phylogenetic analyses of rbc L and ITS sequence data to be sister to Sophora sect. Edwardsia . S. tomentosa and most of the species from sect. Edwardsia share hypogeal germination, exstipulate leaves, and terete filaments. These species have buoyant seeds, and are distributed by ocean currents throughout the pantropics ( S. tomentosa ) and around southern temperate oceanic islands (sect. Edwardsia ). S. tomentosa differs from the species of sect. Edwardsia by its frutescent growth habit, terminal elongate inflorescence and smooth-walled legume. S. macrocarpa is unusual in sect. Edwardsia as its leaves have stipules, the filaments are winged, and the legume is smooth-walled.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 439–446.  相似文献   

2.
A new species of Saussurea , S. erecta S. W. Liu, J. T. Pan & J. Q. Liu sp. nov. , is described from Tibet. It resembles S. kingii but may be distinguished by having distinct stems and glabrous achenes. Saussurea kingii was placed in sect. Pseudoeriocoryne of subgen. Eriocoryne ; this section was circumscribed by acaulescence and an inflorescence with congested capitula surrounded by a rosette of leaves. The discovery of S. erecta with distinct stems, cauline leaves and corymbose capitula blurred the delimitation of sect. Pseudoeriocoryne and suggested that the section may be polyphyletic. Both the close relationship and the significant difference between S. erecta and S. kingii were confirmed by analyses of nrDNA ITS sequences. The resulting phylogenies based on ITS data further suggest that Saussurea sect. Pseudoeriocoryne , as traditionally defined, does not constitute a monophyletic group. The rapid radiation and speciation of Saussurea in the Qinghai-Tibetan Plateau, as inferred from ITS phylogeny, are discussed.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 349–356.  相似文献   

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Ortíz, S. & Oubiña, J.R. 1995. Dicoma hindana (Asteraceae), a new species from Somalia. - Nord. J. Bot. 15: 187–189. Copenhagen. ISSN 0107–055X.
A new species of the genus Dicoma (sect. Psilocoma ), from Somalia, is described. The characteristics by which it can be distinguished from related species are listed.  相似文献   

6.
Nucleotide sequences of 5S rRNA genes (5S rDNA) of 26 wild species of the genus Solanum (sect. Petota) originating from Middle or South America, four Solanum tuberosum breeding lines and one European species, Solanum dulcamara (sect. Dulcamara) were compared with each other and with the 5S rDNA of Lycopersicon esculentum. The length of the repeat ranges from 285 bp to 349 bp. The complete 5S repeat unit consists of the 120-bp long conserved coding region and of a intergenic spacer with a high variability in the central portion as result of deletions/duplications of short motifs demonstrating sequence similarity to box C in the 5S rRNA coding region. Numerous structural rearrangements found in the spacer region can be applied to design species-specific molecular markers for Solanum species involved in breeding programs. Characteristic insertions/deletions (indels) were used to reconstruct phylogenetic relationships among the species studied. S. dulcamara forms a separate clade; L. esculentum is more related to Solanum species of sect. Petota. Conservation of ancestral 5S spacer organization was demonstrated for the representatives of several series of sect. Petota, both Stellata and Rotata. Further rearrangements of the spacer organization occurred in at least four independent lineages: (1) L. esculentum, (2) ser. Polyadenia, (3) other Stellata species from Middle America (ser. Pinnatisecta and Bulbocastana), (4) superser. Rotata. In this last group, series Megistacroloba and Conocibaccata show a common origin, and separation from ser. Tuberosa. Solanum chacoense and Solanum maglia demonstrate a close relatedness to species of ser. Tuberosa and should be included into this group, whereas Solanum bukasovii should be excluded due to conservation of ancestral spacer organization. Three major subgroups may be distinguished for species from ser. Tuberosa, although a high sequence similarity was found here. Several wild species (diploids Solanum phureja and Solanum spegazzinii) probably participated in the natural origin of tetraploid S. tuberosum;others were later used for crossing in breeding programs (e.g. Solanum demissum). Clear separation of Middle-American Stellata species from South-American Stellata and from Middle-American Rotata polyploids is shown. Received: 11 January 2001 / Accepted: 18 April 2001  相似文献   

7.
Hansen, H. V. 1988. A taxonomic revision of the genera Gerbera sect. Isanthus, Leibnitzia (in Asia), and Uechrrirzia (Compositae, Mutisieae). - Nord. J. Bot. 8: 61–76. Copenhagen. ISSN 0107–055X.
The Asiatic part of Compositae tribe Mutisieae subtribe Mutisiinae scapose group is revised. It includes one section of the genus Gerbera , sect. Isanthus with 6 species: G. maxima, G. raphanifolia, G. delavayi, G. henryi, G. nivea , and G. gossypina , the genus Leibnitzia with 4 species, L. anandria, L. knorringiana, L. nepalensis , and L. ruficoma , and the genus Uechtrirzia with 3 species, U. kokanica, U. armena , and U. lacei . The species are mainly distributed in the Himalaya Region and W. China (Yunnan), but some occur in S. USSR, and L. anandria is widespread; Leibnitzia probably also occurs in Central America with 2 endemic species. A distribution map showing the Asiatic range of Gerbera piloselloides (sect. Piloselloides ) is presented.  相似文献   

8.
Munronia yinggelingensis R. J. Zhang, Y. S. Ye & F. W. Xing, a new species of Meliaceae from Hainan, China, is described and illustrated. Notes are also presented on the phenology, ecology and conservation status of the new species. The new species was found growing in the valley rain forests of Yinggeling Nature Reserve at altitudes of 600 m a.s.l. in Gaofeng, Baisha County, Hainan Province, China. It is closely related to Munronia delavayi Franch., but differs in its entire or inconspicuously coarsely serrate margins of leaflets, longer inflorescence (8–30  cm), longer calyx lobes (5 mm), shorter coronal tube (1.2–1.5  cm), with white hairs on both sides, shorter coronal lobes (0.6–0.9  cm) and shorter stamen tube (1.8  cm).  相似文献   

9.
The "spiny solanums," Solanum subgenus Leptostemonum (Solanaceae), comprise a large lineage with over 350 species and include the cultivated eggplant, Solanum melongena. Despite the importance of this subgenus, phylogenetic relationships among these taxa are currently unclear. The present research contributes to this understanding while focusing on Solanum section Acanthophora, a group of ca. 19 species defined by the presence of simple hairs, rather than the stellate hairs common across the rest of subgenus Leptostemonum. In this study we inferred phylogenetic relationships among 29 Solanum taxa, including 14 species of section Acanthophora, using DNA sequence data from two nuclear regions (ITS and the granule-bound starch synthase gene [GBSSI or waxy]) and two chloroplast regions (trnT-trnF and trnS-trnG). This combination of gene regions resulted in a well resolved phylogenetic hypothesis, with results strongly suggesting that Solanum sect. Acanthophora is not monophyletic, although the majority of taxa comprise a monophyletic lineage that is sister to Solanum section Lasiocarpa. Of the four gene regions, waxy was especially useful for phylogenetic inference, with both a high percentage of parsimony-informative sites as well as a low level of homoplasy. Further studies in progress will help elucidate relationships of sect. Acanthophora with respect to other members of subgenus Leptostemonum.  相似文献   

10.
Moyle LC  Nakazato T 《Genetics》2008,179(3):1437-1453
The genetic basis of hybrid sterility can provide insight into the genetic and evolutionary origins of species barriers. We examine the genetics of hybrid incompatibility between two diploid plant species in the plant clade Solanum sect. Lycopersicon. Using a set of near-isogenic lines (NILs) representing the wild species Solanum pennellii (formerly Lycopersicon pennellii) in the genetic background of the cultivated tomato S. lycopersicum (formerly L. esculentum), we found that hybrid pollen and seed infertility are each based on a modest number of loci, male (pollen) and other (seed) incompatibility factors are roughly comparable in number, and seed-infertility QTL act additively or recessively. These findings are remarkably consistent with our previous analysis in a different species pair, S. lycopersicum x S. habrochaites. Data from both studies contrast strongly with data from Drosophila. Finally, QTL for pollen and seed sterility from the two Solanum studies were chromosomally colocalized, indicating a shared evolutionary history for these QTL, a nonrandom genomic distribution of loci causing sterility, and/or a proclivity of certain genes to be involved in hybrid sterility. We show that comparative mapping data can delimit the probable timing of evolution of detected QTL and discern which sterility loci likely evolved earliest among species.  相似文献   

11.
Several Central American species of Piper sect. Macrostachys have obligate associations with ants, in which the ant partner derives food and shelter from modified plant structures and, in turn, protects the plant against fungal infection and herbivory. In addition to these obligate ant-plants (i.e. myrmecophytes), several other species in Piper have resident ants only sometimes (facultative), and still other plant species never have resident ants. Sheathing petioles of sect. Macrostachys form the domatia in which ants nest. Myrmecophytes in sect. Macrostachys have tightly closed petiole sheaths with bases that clasp the stem. These sheathing petioles appear to be the single most important plant character in the association between ants and species of sect. Macrostachys . We examined the structure and variation of petioles in these species, and our results indicate that minor modifications in a small number of petiolar characters make the difference between petioles that are suitable for habitation by ants and those that are not.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 181–191.  相似文献   

12.
Two new, closely related species of Struthanthus (Loranthaceae) are described, S. meridionalis from southern Bolivia and S. prancei from northern Brazil, each showing significant deviations from the generic norm in their inflorescence morphology. In both cases, a very high proportion of inflorescences bear bracteolate and/or ebracteolate monads as lateral units rather than the triads which characterize the rest of the genus. The place of inflorescence morphology in the development of generic concepts in small-flowered neotropical Loranthaceae is briefly reviewed, leaving the two new species in Struthanthus for the time being.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 469–474.  相似文献   

13.
The 5(') external transcribed spacer (ETS) region of ribosomal DNA of 30 species of Solanum sect. Petota and the European Solanum dulcamara were compared. Two structural elements can be distinguished in the ETS: (i). a variable region (VR), demonstrating significant structural rearrangements and (ii). a conservative region (CR), evolving mainly by base substitutions. In VR, a conservative element (CE) with similarity to the ETS of distantly related Nicotiana is present. The ancestral organization of ETS (variant A) was found for non-tuber-bearing species of ser. Etuberosa, tuber-bearing wild potatoes of Central American ser. Bulbocastana, Pinnatisecta, and Polyadenia and S. dulcamara. Duplication of CE took place in the ETS of species from ser. Commersoniana and Circaeifolia (variant B). South American diploids and Mexican polyploids from superser. Rotata also possess two CE, and additionally two duplications around CE1 are present in VR (variant C). Three major lineages could be distinguished: non-tuber-bearing species of ser. Etuberosa, tuber-bearing Central American diploids and all South American species radiated from a common ancestor at early stages of evolution, indicating a South American origin of the tuber-bearing species. Later, Central and South American diploids evolved further as independent lineages. South American species form a monophyletic group composed of series with both stellata and rotata flower morphology. Solanum commersonii represents a sister taxon for all rotata species, whereas ser. Circaeifolia diverged earlier. Two main groups, C1 and C2, may be distinguished for species possessing ETS variant C. C1 contains ser. Megistacroloba, Conicibaccata, Maglia, and Acaulia, whereas all diploids of ser. Tuberosa are combined into C2. A closer relationship of Solanum chacoense (ser. Yungasensa) to the C2 group was found. The origin of polyploid species Solanum maglia, Solanum acaule, Solanum tuberosum, Solanum iopetalum, and Solanum demissum is discussed.  相似文献   

14.
15.
The major cultivated potato, Solanum tuberosum, and six other related cultivated species, are hypothesized to have arisen from a group of weedy relatives indigenous to the central Andes of central Peru, Bolivia, and northern Argentina. A major problem hindering investigations of the origins of the cultivated species has been a continuing debate over the species boundaries of their putative progenitors. This study investigated the morphological phenetic species boundaries of these putative progenitors and five cultivated taxa, here collectively referred to as the Solanum brevicaule complex. Two hundred fifteen accessions of 30 taxa in the S. brevicaule complex and 42 accessions of six taxa outside of the complex were assessed for 53 morphological traits in replicate plots in a common garden, resulting in a total of over 81;t3000 data points. Phenetic analyses of these data are unable to support 30 taxa, suggesting instead a single variable complex at best only weakly divided into three widely intergrading sets of populations: (1) Peruvian and geographically adjacent Bolivian accessions (including wild species and all the cultigens), (2) Bolivian and Argentinian accessions and S. verrucosum from Mexico (including only wild species), and (3) the Bolivian and Argentinian wild species S. oplocense. These and other data suggest that Hawkes's 1990 treatment (The Potato: Evolution, Biodiversity, and Genetic Resources, Smithsonian Institute Press, Washington, DC.) of 232 morphological species is an overestimate for sect. Petota.  相似文献   

16.
The pepino (or pepino dulce:Solanum muricatum) is a domesticate, of interest because of its close relationship to tomatoes and potatoes, because it is enjoying increasing exposure in the international market, and because it is a cultigen with no known wild ancestor. Morphologically this South American native is a member of the Solanum sect. Basarthrum, and as such, is allied to a number of Andean wild species. Data from other studies are combined with results from restriction site analysis of chloroplast and nuclear ribosomal DNA to assay relationships and the potential origin of the pepino. The pepino may have existed in the wild previously and may be represented today only by the cultigen. However, if its ancestors are extant, three wild species—Solanum basendopogon (Perú),S. caripense (Costa Rica through Perú), S. tabanoense (Colombia and Ecuador)—emerge as most likely progenitors. Phylogenetic analyses of 61 accessions, including 27 of the pepino, dependent on chloroplast DNA (cpDNA) and nuclear ribosomal (rDNA) restriction site data show the pepino to be polymorphic, suggest independent origins for some of the cultivars, and most strongly supportS. tabanoense as the progenitor of the cultigen.Solanum caripense also may have been a direct ancestor of the pepino, or may have hybridized subsequent to its origin with the pepino to yield some of the haplotype variation. Similarly, S.cochoae may have hybridized with the pepino. There are no DNA characters supporting the involvement ofS. basendopogon in the origin.  相似文献   

17.
Chloroplast DNA (cpDNA) restriction enzyme site analysis was used to test hypotheses of series and superseries affiliations of 76 taxa, representing 11 of the 13 South American series (material unavailable for two series) of wild potatoes (Solanum sect. Petota) recognized in the latest classification by Hawkes. The cladistic results, combined with those from earlier cpDNA studies of 30 taxa of the Mexican and Central American species (representing eight series; ser. Conicibaccata and ser. Tuberosa have representatives in Mexico and in South America), support four main clades for 17 of the 19 series examined in sect. Petota: (1) the Mexican and Central American diploid species, exclusive of S. bulbocastanum, S. cardiophyllum, and S. verrucosum, (2) S. bulbocastanum and S. cardiophyllum (ser. Bulbocastana, ser. Pinnatisecta), (3) South American diploid species constituting all of ser. Piurana, but also members of ser. Conicibaccata, ser. Megistacroloba, ser. Tuberosa, and ser. Yungasensia, (4) all Mexican and Central American polyploid species (ser. Longipedicellata, ser. Demissa), S. verrucosum (diploid Mexican species in ser. Tuberosa), and South American diploid and polyploid members of ser. Acaulia, ser. Circaeifolia, ser. Commersoniana, ser. Conicibaccata, ser. Cuneoalata, ser. Lignicaulia, ser. Maglia, ser. Megistacroloba, ser. Tuberosa, and ser. Yungasensia. Each of these clades contains morphologically and reproductively very diverse species, and there are no evident morphological features that unite members within a clade to therefore distinguish them. These results strongly suggest a need for a reevaluation of the series and superseries classifications of sect. Petota.  相似文献   

18.
Friis, I. & Wilmot-Dear, C.M. 1988. A revision of the tribe Forsskaoleae (Urticaceae). - Nord. J. Bot. 8: 25–59. Copenhagen. ISSN 0107–055X.
The tribe Forsskaoleae has been revised and the inflorescence and floral structure reinvestigated. The alternative interpretation of the flowers and inflorescences of Forsskaoleae proposed by Rivieres is rejected. A division of the tribe into two subtribes is tentatively maintained. The study of all genera is based on the total available material, with exception of Forsskaolea , of which only the types and some additional material have been studied, and an annotated survey of the six recognized species is presented. In Droguetia seven species are recognized, distributed from tropical and South Africa to Madagascar, the Mascarenes, Java, and India. An infrageneric division of the genus is not tenable. The genus Didymodoxa , for the last hundred years united with Australina , is reestablished with two species, both restricted to eastern and southern Africa. The genus Australina is, within the new delimitation, disjunct between Australia, Tasmania and New Zealand on the one hand and Ethiopia and Kenya on the other. In view of the considerable differences between them, each of the two species is placed in a separate section, sect. Australina and sect. Sarmentago . The lectotypification of Urtica capensis made by Prain is shown to be in conflict with the protologue; a new lectotype is selected, with consequence for the nomenclature of a South African Acalypha species (Euphorbiaceae). All taxa are keyed out and described; distribution maps and illustrations are provided for most taxa.  相似文献   

19.
赖广辉 《广西植物》2018,38(9):1215-1220
该文根据采自华东地区的一些刚竹属植物居群中的可靠花枝标本,结合现场调查和形态解剖观察,描述和增补了白哺鸡竹、瓜水竹、谷雨竹、云和哺鸡竹的花序、假小穗和花部形态特征,并提供了显示花枝外貌和花器官主要特征的照片。瓜水竹的花序呈头序,小花较短,应属于水竹组;而其余3种的花序呈穗状,小花较长,应归隶刚竹组。所有的凭证标本均保存于安徽省广德县林业科学研究所竹类标本室中。  相似文献   

20.
We evaluated chloroplast DNA (cpDNA), isozymes, single to low-copy nuclear DNA (RFLPs), and random amplified polymorphic DNAs (RAPDs) in terms of concordance for genetic distance of 15 accessions each of Solanum etuberosum and S. palustre, and 4 accessions of S. fernandezianum. These self-compatible, diploid (2n=24), and morphologically very similar taxa constitute all species in Solanum sect. Etuberosum, a group of non-tuber-bearing species closely related to Solanum sect. Petota (the potato and its wild relatives). Genetic distance and multidimentional scaling results show general concordance of isozymes, RFLPs and RAPDs between all three taxa; cpDNA shows S. etuberosum and S. palustre to be more similar to each other than to S. fernandezianum. Interspecific sampling variance shows a gradation of resolution from allozyme (low) to RAPD to RFLP (high); while intraspecific comparisons graded from RFLPs (low) to RAPDs (high; lack of sufficient allozyme variability within species precluded comparisons for allozymes). Experimental error was low in RFLPs and RAPDs.Names are necessary to report factually and available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable  相似文献   

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