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1.
 DNA sequences of both 5′ and 3′ regions of the plastid ndhF gene were generated in order to study the position of Patrinia and Nardostachys, to check the potential paraphyletic nature of Patrinieae, and to evaluate the possible link between the tribe and Linnaeaceae. Parsimony analysis showed very strong support for Patrinia as sister to all members of Valerianaceae (including Nardostachys) and indicated the paraphyletic nature of the tribe Patrinieae. Additionally, trees were constructed from available rbcL data separately and supplemented with ndhF sequences. Topologies of these combined cladograms are in agreement with the ndhF phylogeny, suggesting that the traditionally circumscribed Patrinieae can no longer be recognized but must be considered as part of a basal grade in Valerianaceae. Parsimony analysis based on a morphological data set supported a monophyletic Patrinieae; combination with the molecular data showed a paraphyletic Patrinieae. Furthermore, the possible link between Patrinieae and Linnaeaceae is evaluated. Received July 12, 2001 Accepted February 25, 2002  相似文献   
2.
Background and Aims Floral spurs are hollow, tubular outgrowths that typically conceal nectar. By their involvement in specialized pollinator interactions, spurs have ecological and evolutionary significance, often leading to speciation. Despite their importance and diversity in shape and size among angiosperm taxa, detailed investigations of the mechanism of spur development have been conducted only recently.Methods Initiation and growth of the nectar-yielding petal spur of Centranthus ruber ‘Snowcloud’ was investigated throughout seven stages, based on bud size and developmental events. The determination of the frequency of cell division, quantified for the first time in spurs, was conducted by confocal microscopy following 4'',6-diamidino-2-phenylindole (DAPI) staining of mitotic figures. Moreover, using scanning electron microscospy of the outer petal spur surface unobstructed by trichomes, morphometry of epidermal cells was determined throughout development in order to understand the ontogeny of this elongate, hollow tube.Key Results Spur growth from the corolla base initially included diffuse cell divisions identified among epidermal cells as the spur progressed through its early stages. However, cell divisions clearly diminished before a petal spur attained 30 % of its final length of 4·5 mm. Thereafter until anthesis, elongation of individual cells was primarily responsible for the spur’s own extension. Consequently, a prolonged period of anisotropy, wherein epidermal cells elongated almost uniformly in all regions along the petal spur’s longitudinal axis, contributed principally to the spur’s mature length.Conclusions This research demonstrates that anisotropic growth of epidermal cells – in the same orientation as spur elongation – chiefly explains petal spur extension in C. ruber. Representing the inaugural investigation of the cellular basis for spur ontogeny within the Euasterids II clade, this study complements the patterns in Aquilegia species (order Ranunculales, Eudicots) and Linaria vulgaris (order Lamiales, Euasterids I), thereby suggesting the existence of a common underlying mechanism for petal spur ontogeny in disparate dicot lineages.  相似文献   
3.
Transformed roots of V. locusta (Valerianaceae) were obtained through transformation with Agrobacterium rhizogenes strains A4 and ATCC 15834. Six known valepotriates, including diavaltrate, acevaltrate, didrovaltrate, IVHD-valtrate, isovaltrate, and valtrate were the major components detected. An LC/PDA method was used in the quantitation of these compounds in the transformed root extracts. The treatment of transformed roots with biotic (methyl jasmonate, salicylic acid, yeast extract) and abiotic elicitors (CuSO4, HgCl2, CaCl2) was used as a strategy to improve the production of valepotriates. Methyl jasmonate appeared to be the best elicitor for valepotriate production, yielding up to a 7-fold increase in total valepotriate content, while HgCl2 had the most deteriorating effect on the production of valepotriates. Salicylic acid-, CuSO4- and CaCl2-treated roots showed significant increases in the production at a short duration of exposure; the production decreased as the time of elicitation increased. The highest total valepotriate content achieved in this study was 139 mg g–1 DW (13.9%) from transformed roots treated for 10 days with 100 M methyl jasmonate. This amount was >50- and 12-fold higher than the values reported from the cultivated plants and callus culture, respectively, and was comparable to the amount reported from the high valepotriate-producing species Valeriana thalictroides Graebn. The production of diavaltrate, acevaltrate, didrovaltrate, and isovaltrate were significantly higher, while the production of IVHD-valtrate was lower and that of valtrate was similar to that of the control. The IVAL/VAL production ratio was affected by the treatment with methyl jasmonate but not by other elicitors. The use of transformed root cultures in combination with the treatment with biotic and abiotic elicitors offer a new route for high valepotriate production.  相似文献   
4.
Two guaiane-type compounds, nardoguaianone J and K (1 and 2) and two aristolane-type compounds, kanshone F and G (3 and 4), were isolated from Nardostachys chinensis roots. The structures including the absolute configurations were elucidated by spectral means and by comparison of their CD spectra.  相似文献   
5.
l-(+)-Bornesitol was detected in 23 of 33 genera of Gentianaceae investigated. The only subtribe without l-(+)-bornesitol (3 species tested) was Exacinae. None of the five genera of Menyanthaceae examined were found to contain l-(+)-bornesitol.  相似文献   
6.
7.
Bei den hochandinen Valerianaceengattungen Stangea, Belonanthus, Aretiastrum und Phyllactis sowie einigen hochandinen Valeriana-Arten zeigen die persistierenden Achsenabschnitte ein anomales sekundäres Dickenwachstum, dessen wesentliche Züge hier für Stangea, Belonanthus und einige Vertreter der Gattung Valeriana vergleichend betrachtet werden. Das anomale Dickenwachstum vollzieht sich vor allem mit Hilfe neugebildeter markständiger Kambien. In seinem Verlauf werden die Bündel durch Ausbildung eines markständigen Phloem- und Xylemteiles bipolar und nehmen schließlich eine im Querschnitt annähernd sternförmige Struktur an. Von systematischem Interesse ist, daß das anomale Dickenwachstum nicht nur bei den hochgradig abgeleiteten Gattungen der Valeriananae, sondern auch bei Vertretern der Gattung Valeriana selbst auftritt.  相似文献   
8.
Phytochemical investigations on the leaves of Valeriana officinalis L. led to the isolation of 18 compounds, including eight lignans (1–8), three sesquiterpenoids (9–11), five iridoids (12–16), and two aldehydes (17–18) The structure elucidation of isolated compounds was achieved on the basis of NMR and mass spectral data. Among them, three compounds (9–16, 18) are reported from V. officinalis for the first time and one compound (5) was isolated from the genus Valeriana for the first time. In addition, six compounds (2, 4, 6–8, 17) are isolated for the first time from Valerianaceae family. The chemotaxonomic significance of these isolated compounds has also been discussed.  相似文献   
9.
Twenty-one compounds, including four monoterpenoids (14) (two new natural products, 1 and 2), four sesquiterpenes (58), two iridoids (9 and 10), four steroids (1114), five phenolic compounds (1519), and two alkaloids (20 and 21), were isolated from the roots of Valeriana officinalis L. var. Iatifolia Miq. Their chemical structures were established by spectroscopic methods and further confirmed by comparison with published data in the literature. Among them, eight compounds (1, 2, 68, 13, 18, and 21) are being reported from the family Valerianaceae for the first time, and compounds 912 were obtained from V. officinalis for the first time. The chemotaxonomic significance of the isolated compounds is discussed.  相似文献   
10.
报道了发现于江苏省的败酱科(Valerianaceae)新缬草属(Valerianella Mill.)归化植物新记录种:禾穗新缬草[V.locusta(Linn.)Laterr.]。  相似文献   
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