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排序方式: 共有135条查询结果,搜索用时 15 毫秒
1.
本文扼要回顾了松萝属石萝亚属(Usnea subgenus Neuropogon)地衣研究简况,根据形态、化学、分布三者综合的现代地衣物种概念,确认南极乔治王岛菲尔德斯半岛只存在两种石萝即南极石萝(Usnea antarctica)和簇花石萝(Usnea aurantiaco-atra)。除形态、化学特征描述外,详述了这两种石萝在菲尔德斯半岛的生境与分布特征。其中,在藓丛生境中的簇花石萝群体性状分化及其与石生群体性状的比较和讨论是文献中尚未见到的,而生长在木板上的南极石萝则属罕见,其平均生长速率估算为每年增长0.4—1.1mm。在化学上,这两种石萝均属于化学型Ⅰ和化学型Ⅲ,而化学型Ⅱ(含有norstictic,salazinic and usnic acids)不存在于该半岛的两种石萝中。 相似文献
2.
The flavonoid aglycone analysis of 20 Thymus taxa (most Iberic or Balearic endemics) shows the presence of luteolin, apigenin, acacetin, genkwanin, 6-hydroxyluteolin, xanthomicrol, cirsimaritin; four partially identified flavones, of which three are 6-OR-substituted and one flavonol. The differences observed between T. capitatus (L.) Hoffmanns. et Link (subgenus Coridothymus (Reichenb. fil.) Borbás) and the other species belonging to the subgenus Thymus (L.) Jalas, seem enough to maintain the separation of the two groups, but within the same genus, as proposed in Flora Europaea. 相似文献
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二乔玉兰开花过程中花色变化的生理生化机制 总被引:1,自引:0,他引:1
以4年生二乔玉兰不同花期外层花瓣为试材,测定其在开花过程中花瓣色度值、花色苷、类黄酮、可溶性糖含量、细胞pH值以及相关酶活性的变化,以探讨二乔玉兰花色呈色机理。结果显示:(1)随着花期的推移,苯丙氨酸解胺酶(PAL)和查尔酮异构酶(CHI)活性逐渐减弱,细胞pH值逐渐变大,可溶性糖、花色苷、类黄酮含量不断降低,而花瓣明亮度增强,红色度以及彩色度减弱,且不同花期各参数值之间差异显著。(2)花瓣可溶性糖含量、PAL和CHI的活性与其花色素苷、类黄酮含量变化之间呈显著正相关关系,花瓣pH值的变化、明亮度L*值与花色素苷、类黄酮含量之间呈显著负相关,色相值a*与花色苷含量的变化呈显著正相关。研究表明,二乔玉兰花瓣花色苷和类黄酮含量的高低可以影响其花色的深浅,可溶性糖含量、PAL和CHI活性、细胞pH通过参与一定的生理代谢来调节花色素的形成,进而引起二乔玉兰花色色调的改变。 相似文献
5.
Andrzej Zawal 《水生昆虫》2013,35(1):59-66
The morphology of the larval stages of Arrenurus nobilis and A. robustus is described. Particular attention is given to characters that help to distinguish the two species, and to characters defining the subgenus Arrenurus s. str. The larva of A. robustus resembles the larvae of A. papillator and A. pustulator regarding the shape of dorsal plate, excretory pore plate, coxal plate median margins ratios, and the presence of the IIITa8 seta. The shape of the excretory pore plate in A. nobilis resembles the one in Arrenurus (Megaluracarus) mediorotundatus. The shape of dorsal plate and chelicerae is similar to the ones in the Megaluracarus-species A. globator and A. tubulator. The lack of the IIITa8 seta differs from other species of the subgenus Arrenurus s. str. In the pectinate Lp2 and Mh1 setae A. nobilis resembles representatives of the subgenus Arrenurus s. str. This demonstrates the necessity of verifying the taxonomic status of A. nobilis. 相似文献
6.
记述了采自中国腺水螨科1新纪录亚属,拟腺水螨亚属Pseudolebertia Thor,1897及1新纪录种,光足腺水螨Lebertia(Pseudolebertia)abseta Guo,Jin et Asadi,2006.检视标本存放于贵州大学昆虫研究所. 相似文献
7.
A revised classification of the genus Matrona Selys, 1853 using molecular and morphological methods (Odonata: Calopterygidae)
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Xin Yu Junli Xue Matti Hämäläinen Yang Liu Wenjun Bu 《Zoological Journal of the Linnean Society》2015,174(3):473-486
An extensive review of the genus Matrona is presented based on mitochondrial (COI) and nuclear (ITS) sequences from 150 samples which cover all the known taxa of this genus. The separation of two main clades (oreades group: M. oreades, M. corephaea and M. taoi; basilaris group: M. basilaris, M. nigripectus, M. cyanoptera, M. japonica and M. annina) is strongly supported. The classification of all traditional recognized species is confirmed. The Hainan population separates very well from mainland M. basilaris populations, which is also confirmed by geometric morphometric analysis of wing shape. Given the implications of the molecular analysis the genus Matrona is grouped into two subgenera: subgen. Matrona (type species M. basilaris) and D ivortia subgen. nov. (type species M. oreades). A new species, M . ( M .) mazu sp. nov. , from Hainan is described. Brief taxonomic notes on the nine recognized species of the genus are given. Lectotype designations of M. basilaris and M. nigripectus are published. © 2015 The Linnean Society of London 相似文献
8.
Paederus (Harpopaederus) xui Peng & Li, sp. n. (Sichuan: Micang Shan) is described. Additional records of five Harpaederus species are reported. All of these species are illustrated. 相似文献
9.
Sergey G. Ermilov Dorothee Sandmann Bernhard Klarner Rahaju Widyastuti Stefan Scheu 《ZooKeys》2015,(539):11-51
Seven new species of oribatid mites of the genus Galumna are described from litter and soil materials of Sumatra, Indonesia. A new subgenus, Galumna (Atypicogalumna)
subgen. n., is proposed; it differs from all galumnid genera and subgenera by the simultaneous presence of porose areas and sacculi on the notogaster (vs. either porose areas or sacculi present). Galumna (Galumna) calva Starý, 1997 is recorded for the first time in the Oriental region, and Galumna (Galumna) sabahna Mahunka, 1995 is recorded for the first time in the Indonesian fauna. 相似文献
10.
A unique Penicillium isolate from Chinese soil with terverticillate penicilli and ellipsoidal to cylindrical smooth-walled conidia, produces, in addition to the common metabolite ergosterol, copious amounts of an unknown peach-red pigment and the following secondary metabolites: griseofulvin, dechlorogriseofulvin, lichexanthone, roquefortine C, roquefortine D, chrysogine, 2-pyrovoylaminobenzamide, 2-acetyl-quinazolin-4(3H)-one. This isolate, CBS 111235, is described as Penicillium persicinum sp. nov., which belongs to subgenus Penicillium section Chrysogena but is morphologically similar to P. italicum. On the basis of the production of secondary metabolites it resembles P. griseofulvum and P. coprophilum. Sequence data using part of the beta-tubulin gene showed that it is phylogenetically related to P. chrysogenum and P. aethiopicum in section Chrysogena with which it shares both secondary metabolites and ability to grow at 37 degrees C. 相似文献