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1.
Examination of type material ofVerbesina standleyi andCalea pachyphylla shows that the two taxa are conspecific. The older name,C. pachyphylla, has long been associated with the quite remote,C. orizabaensis. The latter is indistinguishable fromC. rupestris andC. guatemalensis; accordingly, these are placed in synonymy.Calea orizabaensis consists of two infraspecific taxa, var.orizabaensis and var.websteri; the latter is described as new.  相似文献   

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Type material of two poorly known species of Macromitrium, described from East Africa and Madagascar, was examined and both were found to belong to the genus Macrocoma. Macromitrium megalosporum Thér. & Naveau was found to be morphologically very close to Macrocoma abyssinica (Müll.Hal.) Vitt., with the only significant difference between these taxa being the large multicellular spores of M. megalosporum, which is also the first report of multicellular spores for the genus Macrocoma. This name is here transferred to Macrocoma as Macrocoma abyssinica var. megalospora (Thér. & Naveau) Wilbraham comb. nov. Macrocoma abyssinica var. megalospora is reported new for the Comoros, which is the first record for the species in the East African Islands. Macromitrium adelphinum Cardot in Grandidier was found to be conspecific with Macrocoma tenuis (Hook. & Grev.) Vitt. subsp. tenuis and an appropriate synonymy is proposed. Macrocoma tenuis. subsp. tenuis is also reported here new to the Comoros.  相似文献   

4.
The classification of Eriosyce subgenus Neoporteria (??subsection?? in the sense of Kattermann) and the role of allopatry/sympatry in the diversification of the group were studied by use of cladistic and predictive distribution modeling methods. We reconstructed the phylogenetic relationships of subgenus Neoporteria by analyzing 38 morphological characters and DNA sequences from two chloroplast regions of 21 taxa from the Chilean subsections of Eriosyce using a Bayesian and maximum likelihood phylogenetic framework. Also, we attempted to find out if the divergence between the sister taxa in the Neoporteria group had been caused by allopatric or sympatric mechanisms. The morphology-based analysis placed E. chilensis basal within the Neoporteria clade and suggested a further broadening of the group by including E. taltalensis var. taltalensis, formerly considered a member of subsection Horridocactus. However, the combined DNA data placed E. sociabilis and E. taltalensis var. taltalensis within the Horridocactus clade, and placed E. chilensis with E. subgibbosa var. litoralis. The broad concept of E. subgibbosa sensu Kattermann (comprising seven infraspecific taxa), was rejected by our combined molecular results. Finally, our results corroborated changes in subsection Neoporteria proposed by various authors and suggested further modifications within Neoporteria. The analyses of the degree of geographic overlap of the predicted distributions indicated null overlap between the sister taxa, and one probable hybrid origin of E. chilensis, indicating that evolutionary divergence is mainly caused by an allopatric process associated with climatic tolerance.  相似文献   

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ABSTRACT

Cupressus sempervirens L. var. pyramidalis and C. sempervirens var. horizontalis were examined for their pollen morphometry and ultrastructure to verify whether, in addition to phenotype, pollen could also show characteristics useful to discriminate the two infraspecific taxa. C. sempervirens var. pyramidalis compared to C. sempervirens var. horizontalis has mainly larger, subcircular pollen with a higher percentage of apolar and germinating grains, and a wall with thicker intine; the cytoplasm has a greater number of callose-containing vesicles. C. sempervirens var. horizontalis has pollen distributed in five classes of shape. In addition it is smaller and shows a higher percentage of ruptured grains, and a lower percentage of germination in vitro. The cytoplasm contains vesicles rich in callose and also a higher amount of osmophilic bodies. Pollen grains in both varietas contain only one cell at dispersal. The reported differences in pollen morphometry, structure and biology, together with the phenotypic characteristics of the tree, support the validity of two infraspecific taxa.  相似文献   

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The taxonomy of theScutellaria pekinensis complex has been ambiguous and problematic, because morphological characters are variable. To elucidate the taxonomic structure of the Korean taxa belonging to the complex, 29 characters were measured from 99 individuals collected from 96 localities and analyzed by factor analysis, cluster analysis, and discriminant analysis. The results supported the recognition of four infraspecific taxa ofS. pekinensis Maxim, in Korea: var.ussuriensis (Regel) Handel-Mazzetti, var.alpina (Nakai) Hara, var.transitra (Makino) Hara, and var.maxima S. Kim et S. Lee. Key characters distinguishing the four varieties were inferred on the basis of multivariante analyses.  相似文献   

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Chloroplast DNA (cpDNA) restriction site variation was examined in five species ofDesmodium subgenusPodocarpium (Leguminosae; Papilionoideae; Desmodieae). Twenty four phylogenetically informative cpDNA mutations were scored. The cladistic analysis of characters based on the 24 mutations resulted in the most parsimonious tree which supports the monophyly of the subgenus.Desmodium elegans of subgenusDollinera was the sister group of subgenusPodocarpium in this tree. The groupings obtained from the cpDNA characters were consistent with the present infrageneric classification system for the subgenus except for the infraspecific taxa ofD. podocarpum. Three groups withinD. podocarpum, which were incongruent with the infraspecific classification of the species, were distinguished by a total of four site mutations. The first group consisted of subsp.podocarpum, subsp.fallax, and subsp.oxyphyllum var.oxyphyllum; the second subsp.oxyphyllum var.oxyphyllum; and the last subsp.oxyphyllum var.oxyphyllum and var.mandshuricum.  相似文献   

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Two diastereoisomers of 4-carboxy-4-hydroxy-2-aminoadipic acid have been isolated from leaves and inflorescences of Caylusea abyssinica. Green parts of the plant also contain appreciable amounts of the two diastereoisomers of 4-hydroxy-4-methylglutamic acid, 3-(3-carboxyphenyl)alanine, (3-carboxyphenyl)glycine, 3-(3-carboxy-4-hydroxyphenyl)alanine, (3-carboxy-4-hydroxyphenyl)glycine and in low concentration 2-aminoadipic acid, saccharopine [(2S, 2′S)-N6-(2-glutaryl)lysine] and some γ-glutamyl peptides. The acidic amino acids were separated from other amino acids on an Ecteola ion exchange column with M pyridine as eluant.  相似文献   

13.
Current taxonomic interpretations ofSolanum microdontum Bitter partition the species into two or three infraspecific taxa, variously recognized as subspecies or varieties. The present study reexamines these taxa using morphological data from four individuals each of 69 accessions from most of the range of the species, planted in a common field plot. Our results show that the character states used to recognize infraspecific taxa inS. microdontum often vary within accessions and have no correlation with geography. We conclude that past hypotheses have used typological concepts and that infraspecific taxa are not warranted. This study questions other hypotheses of infraspecific taxa in sect.Petota.  相似文献   

14.
Polyploids are defined as either autopolyploids or allopolyploids, depending on their mode of origin and/or chromosome pairing behaviour. Autopolyploids have chromosome sets that are the result of the duplication or combination of related genomes (e.g., AAAA), while allopolyploids result from the combination of sets of chromosomes from two or more different taxa (e.g., AABB, AABBCC). Allopolyploids are expected to show preferential pairing of homologous chromosomes from within each parental sub-genome, leading to disomic inheritance. In contrast, autopolyploids are expected to show random pairing of chromosomes (non-preferential pairing), potentially leading to polysomic inheritance. The two main cultivated taxa of Actinidia (kiwifruit) are A. chinensis (2x and 4x) and A. chinensis var. deliciosa (6x). There is debate whether A. chinensis var. deliciosa is an autopolyploid derived solely from A. chinensis or whether it is an allopolyploid derived from A. chinensis and one or two other Actinidia taxa. To investigate whether preferential or non-preferential chromosome pairing occurs in A. chinensis var. deliciosa, the inheritance of microsatellite alleles was analysed in the tetraploid progeny of a cross between A. chinensis var. deliciosa and the distantly related Actinidia eriantha Benth. (2x). The frequencies of inherited microsatellite allelic combinations in the hybrids suggested that non-preferential chromosome pairing had occurred in the A. chinensis var. deliciosa parent. Meiotic chromosome analysis showed predominantly bivalent formation in A. chinensis var. deliciosa, but a low frequency of quadrivalent chromosome formations was observed (1 observed in 20 pollen mother cells).  相似文献   

15.
The main aim of this study is to compare all taxa from the Pinus kesiya complex and related P. tabuliformis using statistical, ordination and discrimination techniques focusing on ten most discriminating morphological traits. Special emphasis was placed on the recently described taxa Pinus densata subsp. tibetica and P. × naxiorum (=P. yunnanensis × P. densata). Population comparisons of the particular main geographic distribution areas of Pinus kesiya, P. densata subsp. tibetica and P. yunnanensis were also conducted separately within each mentioned taxon using the same data. Pinus densata subsp. tibetica proved to be sufficiently morphologically differentiated from subsp. densata as well as from other species of the P. kesiya complex and P. tabuliformis. The recently originating hybrid P. × naxiorum appears to be intermediate between its parents. The unique shrubby taxon P. densata var. pygmaea is clearly closer to P. densata than to P. yunnanensis, to which it has been classified in Chinese floras. Populations of four distant Pinus kesiya geographic distribution areas lack substantial differences that would support the recognition of infraspecific taxa such as subsp. insularis or var. langbianensis. Pinus yunnanensis is very similar to P. kesiya, with only one trait, leaf length, being significantly different.  相似文献   

16.
More than 50 collections of five species forming the Achillea nobilis group were analysed for their leaf flavonoid complement. Major accumulation trends were found to be C-glycosylflavones and flavonol 3-O-glycosides. The most common pattern consisted of the C-8-glycosylfiavones (vitexin and orientin), the C-6-glycosylflavone (isoörientin) together with minor amounts of di-C-glycosylapigenins and quercetin 3-O-glycosides. Additionally, C-6-glycosylflavones (isovitexin) and their 7-methyl ethers swertisin and swertiajaponin were sporadically accumulated, characterizing particularly two subspecies of A. nobilis. Whereas C-glycosylflavone dominated profiles were typical of most species, two taxa exhibited a flavonol dominated profile (A. ligustica; A. virescens p.p.). Regarding the infraspecific and interpopulational variations of flavonoid accumulation trends, their systematic and ecological significance is briefly discussed.  相似文献   

17.
Flavonoid compounds from 36 of the 38 known taxa of the genusArceuthobium (dwarf mistletoes) were examined. The flavonoid chemistry of the genus is rather uniform, all taxa producing 3-O-glycosides of the flavonols quercetin and myricetin. No infraspecific chemical variation was encountered, and in those instances where subspecific taxa are recognized, their chemistry was uniform. At the subgeneric level, members of subgenusArceuthobium synthesize primarily glucosides, whereas galactosides are more common in subgenusVaginata. In two of the four Old World species of subgenusArceuthobium (A. juniperi- procerae andA. oxycedri) only myricetin 3-O-glucoside was detected. There are no absolute flavonoid differences between subgenera, sections, or series. On the other hand, flavonoids are useful in several instances at the species level. In several cases, chemical data lend support to the recognition of species which in the past have been considered doubtfully distinct on the basis of morphology.  相似文献   

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Lectotypes are designated for 174 names of taxa described based on material from the Swedish province of Dalarna and accepted to belong to Hieracium sect. Hieracium , sect. Bifida and sect. Vulgata . The taxonomic and nomenclatural implications, i.e. taxonomic synonyms and infraspecific taxa not worthy of taxonomic recognition, of the lectotypifications are discussed. Three new combinations, H. mundulifolium (Johanss.) T. Tyler, H. oligasterum (Johanss. & Sam.) T. Tyler and H. transtrandense T. Tyler, are proposed to accommodate the infraspecific taxa H. gilvocaniceps Johanss. var. mundulifolium Johanss., H. expallidiforme (Dahlst. ex. Stenstr.) Dahlst. var. oligasterum Johanss. & Sam. and H. insuccatum Johanss. var. occidentale Johanss. & Sam. respectively, when treated at the rank of species.  相似文献   

19.
Twelve Salpichroa taxa have been phytochemically analyzed. From the aerial parts of Sscandens, four known salpichrolides A, C, I, S, and an unreported withanolide named salpichrolide V ( 1 ), were isolated. In Sdependens, Sgayi, Sglandulosa subsp. glandulosa, Sglandulosa subps. weddellii, Sleucantha, Smicrantha, Smicroloba, Sproboscidea, Sramosissima, Stristis var. tristis, and Sweberbauerii, no withanolides were found. The chemical content of ca. 85% of the Salpichroa taxa is in agreement with molecular studies, which suggest that Salpichroa and Jaborosa, a genus considered morphologically close to Salpichroa, are distant in the systematic of the Solanoideae subfamily. Moreover, the in vitro cytotoxic activity of a set of natural salpichrolides and derivatives was examined against two prostate carcinoma cell lines (PC3 and LNCaP) and two human breast cancer cell lines (MCF‐7 and T47D). Several compounds showed moderate activity (IC50 = 64.91 – 29.97 μm ).  相似文献   

20.
Combretum stylesii O.Maurin, Jordaan & A.E.van Wyk, a liana or slender tree with scrambling branches from the Tugela River Valley (KwaZulu-Natal), South Africa, is described. Molecular data supports its placement in subgenus Combretum section Ciliatipetala with its closest relative Combretum edwardsii. The new species differs from C. edwardsii in having, amongst others, a single mature leaf form, leaves softly textured, with whitish hairs, often with drooping habit, shorter leaf petioles (less than 5 mm), and less complex 8-celled leaf scales. A key to the species and infraspecific taxa of section Ciliatipetala in the Flora of southern Africa region is provided.  相似文献   

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