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31.
Melica (Poaceae) consist of about 92 species distributed across temperate regions of the world. Within section Dalycum, Melica ciliata sensu lato forms a taxonomic complex of several species and subspecies with clinal morphological variation causing conflicting identifications. To resolve taxonomic confusion, we used three complementary approaches, through molecular, morphological, and phytoecological analyses. The double-digest restriction-associated DNA markers significantly support the monophyly of three taxa: (i) the Mediterranean Melica magnolii, (ii) the Eurasian Melica transsilvanica subsp. transsilvanica, and (iii) the west-European M. ciliata subsp. glauca. This differentiation is corroborated by the analysis of 22 morphometric variables. Furthermore, phytoecological analysis of 221 floristic inventories revealed habitat distinctions among these taxa. Our approach of integrative taxonomy argues for a specific distinction for these three taxa, and we include a key to separate these forms. These new molecular data on the section Dalycum, subsection Ciliatae, call for further phylogenetic analyses including samples of M. ciliata subsp. ciliata and other East-Mediterranean and South African taxa.  相似文献   
32.
香椿人工林和天然林木材纤维形态和化学成分比较研究   总被引:7,自引:0,他引:7  
通过对香椿人工林和天然林木材纤维形态和化学成分的比较分析,揭示了香椿人工林木材纤维形态的特征及径向变化规律,以及人工林和天然林木材纤维形态和化学成分的差异。结果表明,香椿人工林的工艺成熟期为10年左右,其木材纤维长度和长宽比小于天然林,宽度大于天然林;纤维素、戊聚糖和木素含量均稍高于天然林;灰分和抽出物含量均低于天然林。香椿木材可作为林产工业纤维材料使用。  相似文献   
33.
上海地区悬铃木方翅网蝽的生活史及发生情况   总被引:2,自引:0,他引:2  
观察悬铃木方翅网蝽Corythucha ciliata(Say)在上海的生活史和生活习性,并对其在上海的发生情况进行调查。悬铃木方翅网蝽在上海1年发生5代,第5代成虫于10月中下旬主要在悬铃木主干和支干的树皮下越冬,4月上旬越冬成虫上树为害,4月下旬开始产卵,5月上旬始见第1代若虫,第1代若虫期17~18d,世代历期约30d,7~8月间世代重叠现象明显。悬铃木方翅网蝽在上海11个区均有发生,株被害率最高的4条道路分别为徐汇区龙华西路、肇嘉浜路、松江区人民北路及长宁区延安西路,为害率达100%。为害程度最严重的的3条道路分别为松江区人民北路、长宁区延安西路和水城南路,虫情指数分别达95.6%、76.7%和72.2%。  相似文献   
34.
来自12个种源的70个香椿(Toona sinensis)优树子代在福建省永春县和华安县进行造林测定试验,调查2年生香椿优树子代测定林生长情况。结果表明,华安2年生香椿优树子代树高1.10~2.80 m,地径1.24~3.72 cm,永春2年生香椿优树子代树高0.91~2.71 m,地径1.18~3.68 cm,华安和永春两个试验点内不同香椿家系的树高和地径差异达到极显著水平(P<0.01)。华安试验点树高和地径的变异系数分别为20.22%和23.68%,初步选出6个早期生长表现优秀的家系,平均树高和地径分别为2.55 m和3.44 cm,平均遗传增益分别为23.70%和30.16%;永春试验点树高和地径的变异系数分别为26.44%和26.48%,初步选出19个早期生长表现优秀的家系,平均树高和地径分别为2.52 m和3.34 cm,平均遗传增益分别为25.07%和24.96%。通过树高和地径的聚类分析与生长比较,70个参试家系可分为优、良、中、差和极差5个类别。综合2个试验点生长表现,初步认定4号、23号、53号和65号等4个家系为优良家系。  相似文献   
35.
Wang JR  Shen Q  Fang L  Peng SY  Yang YM  Li J  Liu HL  Guo YW 《Steroids》2011,76(6):571-576
Five new pregnane steroids, toonasterones A (1), B (2), (Z)-aglawone (3), (Z)-toonasterone C (4), and (E)-toonasterone C (5), were isolated from the stem bark of Toona ciliata var. pubescens. Their structures were elucidated by means of detailed spectroscopic (IR, MS, and 2D NMR) analysis, and the stereochemistry of 1 was secured by X-ray diffraction analysis. (Z)-aglawone (3) exhibited moderate inhibitory activity of protein tyrosine phosphatase 1B (PTP1B), a potential drug target for treatment of type-II diabetes and obesity, with an IC50 value of 1.12 μg/mL.  相似文献   
36.
设计正交实验对酶解水提法进行优化,以浸提液中总黄酮得率作为考察指标。采用最佳提取方法提取太和产香椿5个品种的总黄酮,比较其含量大小。结果表明酶解水提法的最佳提取条件是料液比1∶40。酶用量15U/g,酶解时间90min,酶解后水提时间120min。红油椿的总黄酮含量最高,黑油椿次之,其次是红椿、青椿,毛椿的总黄酮含量最少。  相似文献   
37.
Collected from Chinese mainland, 25 samples of Toona sinensis seed were planted in a standard garden. Three years later, samples were analyzed with random amplified polymorphic DNA (RAPD) and isoenzymes variants of cytochrome oxidase and peroxidases. Results of RAPD and isoenzymes variants were analyzed with software POPGENE32 and SPSS10.0 respectively. Phylogenetic trees were calculated from the clustered result of RAPD and isoenzymes variants. Such additional factors as leaves color, latitude and altitude of original seeds were analyzed at the same time. Our result suggested that a general similarity is concurred with the three analyses as RAPD, isoenzymes variants analysis of peroxidases and cytochrome oxidase. Two clusters can be separated from the sample collected as southern and northern ones. In the evolutionary history, a migrating route in the direction from West-South to East-North and with sequential differentiation in the direction South-North can be decided if only it is true with the argument that Toona sinensis came from tropic Asia, the border of east-north India and Burma.  相似文献   
38.
BACKGROUND AND AIMS: Germination and seedling establishment, which are critical stages in the regeneration process of plant populations, may be subjected to natural selection and adaptive evolution. The aims of this work were to assess the main limitations on offspring performance of Silene ciliata, a high mountain Mediterranean plant, and to test whether local adaptation at small spatial scales has a significant effect on the success of establishment. METHODS: Reciprocal sowing experiments were carried out among three populations of the species to test for evidence of local adaptation on seedling emergence, survival and size. Studied populations were located at the southernmost margin of the species' range, along the local elevation gradient that leads to a drought stress gradient. KEY RESULTS: Drought stress in summer was the main cause of seedling mortality even though germination mainly occurred immediately after snowmelt to make the best use of soil moisture. The results support the hypothesis that species perform better at the centre of their altitudinal range than at the boundaries. Evidence was also found of local adaptation in seedling survival and growth along the whole gradient. CONCLUSIONS: The local adaptation acting on seedling emergence and survival favours the persistence of remnant populations on the altitudinal and latitudinal margins of mountain species. In a global warming context, such processes may help to counteract the contraction of this species' ranges and the consequent loss of habitat area.  相似文献   
39.
Galinsoga ciliata Raf. Blake like Galinsoga parviflora Cav., comes from the Andes region. The chemical composition, activity and use are similar for both species. Galinsoga species are used in folk medicine as anti-inflammatory agents and accelerators for wound healing. Extracts are applied topically onto the skin to treat dermatological diseases, eczemas, lichens and hard-healing-wounds, and also to treat snakebites. Orally they used to cure flu and colds.In the studies using HPTLC method, different stationary phases, including unmodified silica gel, silica gels modified with CN, NH2, DIOL and RP18 groups were tried. The best separation of the tested compounds was achieved on silica gel plates, when as mobile phases mixtures – ethyl acetate–acetic acid–formic acid–water (100:11:11:26, v/v/v/v), ethyl acetate–methanol–formic acid–water (50:3:4:6, v/v/v/v) and ethyl acetate–methyl ethyl ketone–formic acid–water (30:9:3:3, v/v/v/v) – were used. Using reference substances, in the examined extracts the presence of flavonoids: patulitrin, quercimeritrin, quercitagetrin, and phenolic acids – caffeic and chlorogenic acids was found.HPLC analyses of extracts were carried out on a reversed-phase Zorbax SB column (150 mm × 2.1 mm, 1.9 μm). The mobile phase (A) was water/acetonitrile/formic acid (95:5:0.1, v/v/v) and the mobile phase (B) was acetonitrile/formic acid (100:0.1, v/v). A linear gradient system was used: 0–30 min, 1–30% B. Application of HPLC-DAD-MS method confirmed the results obtained by HPTLC method. Moreover, in the tested extracts the presence of caffeoylglucaric acids as dominating compounds was detected.  相似文献   
40.
Fourteen compounds have been obtained from the Elsholtzia ciliata (Thund.) Hyland. Their structures were identified by spectral and chemical methods as following: Ⅰ. 6-methyl-tritriacontane, Ⅱ. 13-cyclohexyl-hexoacosane, Ⅲ. β-sitosterol, Ⅳa. palmitic acid, Ⅳb. linoleic acid, Ⅳc. linolenic acid, Ⅴ. ursolic acid, Ⅵ. 5-hydroxy--6, 7-dimethoxyflavone, Ⅶ. 5-hyd-foxy-7, 8-dimethoxyflavone, Ⅷ. 5,7-dihydroxy-4'-methoxyflavone, Ⅸ. 5-hydroxy-7,4'-dime-thoxyflavone, Ⅹ.β-sitosterol-β-D-glucoside, Ⅺ. 5-hydroxy-6-methylflavanone-7-O-α-D-galacopy-ranoside, Ⅻ. acacetin-7-O-β-glucoside. Among all the compounds, Ⅺ is a new compound. Except for Ⅳb and Ⅳc, the other twelve compounds were first found in this plant.  相似文献   
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