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Agapetes yingjiangensis (Ericaceae), a new epiphytic species of A. ser. Longifiles from Yunnan,China
Agapetes yingjiangensis (Ericaceae), a new species from Yingjiang County, Yunnan Province, China is described and illustrated. This new species is somewhat similar to A. mannii Hemsl., but differs in having brown‐hirsute young branches, acute mucronate apex of the leaf blade and sparsely hirsute pedicel, calyx tube and corolla. A key to Chinese species with small (less than 2.5 cm) entire leaves in Agapetes sect. Agapetes ser. Longifiles is included. 相似文献
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ESTRELA FIGUEIREDO FLS 《Botanical journal of the Linnean Society. Linnean Society of London》2001,136(2):179-205
A revision of the genus Calvoa Hook. f. (Melastomataceae) is presented. Principal Component Analyses (PCA) and Cluster Analyses (UPGMA) were performed to elucidate three cases of difficult species delimitation and infraspecific variation, with the following results. (1) The separation between C. crassinoda Hook. f. and C. grandifolia Cogn. was clear in the results obtained with both methods. (2) The group of the West-Central African species Calvoa angolensis A. Fern. & R. Fern., C. calliantha Jacq.-Fél., C. monticola A. Chev., C. pulcherrima Gilg ex Engl., C. sapinii De Wild., C. seretii De Wild., C. sinuata Hook. f. and C. subquinquenervia De Wild, proved difficult to resolve with either analysis, but the Cluster Analysis produced results which are more consistent with the identification of the specimens. (3) Neither of the two analyses supported the recognition of infraspecific categories in Calvoa orientalis Taub. Eighteen species are recognized in the genus. The new species Calvoa Jacques-felixii E. Figueiredo is described and the new combination Calvoa seretii subsp. wildemaniana (Exell) E. Figueiredo is made. Four lectotypes are designated. The conservation status of some taxa is discussed. Six species are considered rare and possibly under threat. 相似文献
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General characteristics of light sensitivity of Impatients wallerana seeds were investigated. Germination was absolutely dependent on light, irrespective of temperature. High percentages of germination were obtained by exposure to long periods of illumination or, alternatively, to several repeated short irradiations with red light. In this case, responsiveness to light was not altered by increasing either the initial incubation period in darkness or the dark intervals between short exposures. Effects of red light were reversed by far-red light, thus demonstrating the involvement of phytochrome. Evidence was presented for an interactive effect, of unknown physiological nature between red and far-red light on the germination of the seeds.Abbreviations Pr
phytochrome, red light absorbing form
- Pfr
phytochrome far-red absorbing form 相似文献
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A new diterpenoid bisepoxide, neotriptetraolide, was isolated from the leaves and root of Tripterygium wilfordii Hook. f. Neotriptetraolide was crystallized from CH3OH as colorless needle-like crystal, with amp of 237~238 ℃. Its molecular formula was C20H2608. Its structure was elucidated by means of spectral analysis (UV, IR, MS, 1H-NMR, 13C- NMR, 2D-COSY, 2D-NOESY, 13C-NOE, and selective long-range DEPT spectroscopy) and the computation of molecular mechanics and molecular graph. 相似文献
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Seven polymorphic microsatellite loci have been characterized for investigating population structure in the patchily distributed herb Begonia sutherlandii. Two loci (BSU3 and BSU4) exhibited population specific null alleles; primer redesign and allele sequencing for one of these loci showed two transition mutations in the original primer site. Two loci exhibited imperfect repeat polymorphisms due to single base pair indels in the flanking region (locus BSU6) and in the microsatellite region itself (BSU7). Transversion mutations were also found in the microsatellite region of locus BSU7. The remaining three loci amplified in all individuals tested and appeared to conform to a simple stepwise mutation pattern. 相似文献
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对油果樟属(Syndiclis Hook.f.)及其近缘属琼楠属(Beilschmiedia Nees)、孔药楠属(Sinopora J.Li et al.)、国产土楠属(Endiandra R.Br.)和Potameia的网脉结构进行了观察。结果表明,它们的网脉结构可分为3种类型:A型网格小且小脉无游离末端;B型网格小但有不分枝或简单分枝的游离末端;C型网格粗且网脉末端多分枝。琼楠属网脉结构多样,具有全部3种类型,其余4属均仅有1种类型,油果樟属、孔药楠属以及土楠属均为A型,明显不同于Potameia的C型网脉结构。 相似文献
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Olivier Placide Noté Azefack Léon Tapondjou Anne-Claire Mitaine-offer Tomofumi Miyamoto Dieudonné Emmanuel Pegnyemb Marie-Aleth Lacaille-Dubois 《Phytochemistry letters》2013,6(4):505-510
One new triterpenoid saponin, named piptadeniaoside (1), along with two known saponins (2–3) have been isolated from the stem bark of Piptadeniastrum africanum. After previous isolation of flavone derivatives from this plant, new phytochemical investigations were performed for its saponin content. Their structures were established by direct interpretation of their spectral data, mainly HRESIMS, 1D NMR (1H, 13C NMR, DEPT) and 2D NMR (COSY, NOESY, HSQC and HMBC), and by comparison with the literature data. 相似文献
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ILSE BREITWIESER JOSEPHINE M. WARD 《Botanical journal of the Linnean Society. Linnean Society of London》1998,126(3):217-235
Leaf anatomy is compared for all species of Raoulia. The species are tabulated according to their lamina structure. Noteworthy anatomical features are lamina type and grade of differentiation, stomatal position, epidermal and cuticle thickness, shape of mesophyll cells, presence or absence of central clear cells, sclerenchyma caps, abaxial collenchyma and protruding midrib. It is shown that leaf anatomy data provide characters which are taxonomically useful in Raoulia. The main subgenera are supported except that the leaf anatomy of R. haastii is anomalous and that of R. youngii is typical of R. subg. Raoulia rather than R. subg. Psychrophyton. The leaf anatomy of R. petriensis is unique in the genus. 相似文献
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Jaime Pacheco-Trejo Teresa Terrazas Helga Ochoterena 《Plant Systematics and Evolution》2009,281(1-4):137-149
We examined 532 specimens representing eight species of Didymaea (Rubiaceae) to describe their leaf architecture. Characters observed in the herbarium specimens and cleared leaves were leaf base, apex, and margin; trichome type and distribution; vein orders from primary to higher order veins, veinlets, and ultimate marginal vein. Six morphometric variables were analyzed using variance and principal component analysis to identify which characters are useful to distinguish species. Most of the species present brochidodromous venation pattern, except D. hispidula, which has eucamptodromous venation pattern; Didymaea floribunda is unique in having cylindrical and bicellular trichomes. Principal component analysis revealed that 78% of the total variation is mainly related to leaf maximum width. Variance analysis showed significant differences between D. microflosculosa and the other species. Architectural features were useful for differentiating all the species, and an identification key for the species of Didymaea based only on leaf characters is presented. 相似文献
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以领春木(Eupteleapleiospermum Hook.f.etThoms.)种子幼胚为试验材料,对领春木体细胞胚胎发生进行了研究。结果表明:在附加1.0mg·L-1 2,4.D+0.5mg·L-1 6-BA+3%蔗糖+0.8%琼脂的Ms培养基上可诱导出愈伤组织。愈伤组织在附加0.5mg·L-1 NAA+0.5mg·L-1 6.BA的培养基上可形成体细胞胚;体胚在附加0.5mg·L-1 6-BA+0.05mg·L-1 NAA+0.1%PVP的1/2MS培养基上能大量增殖;将成熟体胚转移到不添加任何植物生长调节剂的MS培养基上,培养60d,形成正常植株。 相似文献
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【背景】雷公藤是一种传统中药,具有多种药理活性和较高的应用价值。但由于产量少、提取过程复杂而限制了其在临床上的应用。植物内生真菌的次级代谢产物能够产生相似的药理活性,有望解决植物资源匮乏的难题,成为新药筛选的潜在资源。【目的】从卫矛科植物雷公藤中分离内生真菌,对其产物的体外抗菌活性及抗肿瘤活性进行测定,并利用活性菌株对雷公藤粗提物进行转化,以达到增效减毒的作用。【方法】采用组织块法从雷公藤茎中分离内生真菌;打孔法测定发酵产物对金黄色葡萄球菌和大肠埃希氏菌的抑菌活性;MTT(噻唑蓝)比色法测定发酵产物及转化产物的抗肿瘤活性;ITS(Internal transcribed spacer)序列测序分析确定活性菌株的种属。【结果】从雷公藤茎中分离得到43株内生真菌,其中5株对金黄色葡萄球菌有抑菌作用,LGT7几乎与1μg/mL青霉素钠的作用效果相当;6株对MCF-7、SKOV3细胞有抗肿瘤活性,LGT7、LGT41对肿瘤细胞生长抑制率达90%以上;4株对雷公藤粗提物具有转化活性。活性菌株分别被鉴定为拟茎点霉和腐皮壳属。【结论】雷公藤内生真菌具有抗菌抗肿瘤作用,并可以通过转化产生增效减毒作用。 相似文献
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