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Age structure and niche of the endangered Magnolia sieboldii in Huangshan Mountain
黄山濒危植物小花木兰生态位与年龄结构研究
WANG Li-Long,WANG Guang-Lin,HUANG Yong-Jie,LI Jing,LIU Deng-Yi,
王立龙,王广林,黄永杰,李晶,刘登义
生态学报 , 2006,
Abstract: Based on the data collected from the plots investigation along with the implementation Levins,Shannon weiner and niche overlap formulas,this paper investigated the niche breadth values and niche overlap values of the main tree species were measured in the natural forestry of Magnolia sieboldii and the age structure of Magnolia sieboldii The results showed that: The descending order of niche breadth value was to some extent in accordance with that of important values,but Enkianthus chinensis is different from others for its strong adaptability.The values of niche overlap were relevant to niche breadth in that the populations with wide niche breadths usually had high overlap values with the other populations.The niche overlap values among the populations with the same or similar environment requirements and similar biological properties were also higher.For example,Magnolia sieboldii and Enkianthus chinensis,with the same shade-tolerant characteristic,had high overlap value.Through this niche research it was shown that Magnolia sieboldii,is characterized by scattered distribution,poor regeneration and less competitive advantages with associated species in the community.Thus,Magnolia sieboldii was easily influenced by community variation.It was found that populations with the same ecological characteristics could form a fine relation in the same habitat when resources were sufficient.This finding provided further support for linsizu's theory that the relationship between niche overlap and competition was not positively correlated.It was also found that the age structure of Magnolia sieboldii was not integrated as young trees were absent,Such inconsistencies threaten population development.Water condition, for example,was an ecological factor which affected the presence of Magnolia sieboldii,and its high altitude distribution showed its need for low temperature.Magnolia Sieboldii grew well in Sanhuawu,while,its age structure in Qinliangtai was older than those in other plots,Qinliangtai and Sanhuawu can be regarded as key conservation habitats and it can be noted that the dynamic differences brought about by the variance between the two habitats above would merit further exploration.
Growth Inhibitory, Bactericidal, and Morphostructural Effects of Dehydrocostus Lactone from Magnolia sieboldii Leaves on Antibiotic-Susceptible and -Resistant Strains of Helicobacter pylori  [PDF]
Hyun-Kyung Lee, Ha Eun Song, Haeng-Byung Lee, Cheol-Soo Kim, Mamoru Koketsu, Luong Thi My Ngan, Young-Joon Ahn
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0095530
Abstract: Helicobacter pylori is associated with various diseases of the upper gastrointestinal tract, such as gastric inflammation and duodenal and gastric ulcers. The aim of the study was to assess anti-H. pylori effects of the sesquiterpene lactone dehydrocostus lactone (DCL) from Magnolia sieboldii leaves, compared to commercial pure DCL, two previously known sesquiterpene lactones (costunolide and parthenolide), (–)-epigallocatechin gallate, and four antibiotics. The antibacterial activity of natural DCL toward antibiotic-susceptible H. pylori ATCC 700392 and H. pylori ATCC 700824 strains (MIC, 4.9 and 4.4 mg/L) was similar to that of commercial DCL and was more effective than costunolide, parthenolide, and EGCG. The activity of DCL was slightly lower than that of metronidazole (MIC, 1.10 and 1.07 mg/L). The antibacterial activity of DCL was virtually identical toward susceptible and resistant strains, even though resistance to amoxicillin (MIC, 11.1 mg/L for PED 503G strain), clarithromycin (49.8 mg/L for PED 3582GA strain), metronidazole (21.6 mg/L for H. pylori ATCC 43504 strain; 71.1 mg/L for 221 strain), or tetracycline (14.2 mg/L for B strain) was observed. This finding indicates that DCL and the antibiotics do not share a common mode of action. The bactericidal activity of DCL toward H. pylori ATCC 43504 was not affected by pH values examined (4.0–7.0). DCL caused considerable conversion to coccoid form (94 versus 49% at 8 and 4 mg/L of DCL for 48 h). The Western blot analysis revealed that urease subunits (UreA and UreB) of H. pylori ATCC 43504 were not affected by 10 mM of DCL, whereas UreA monomer band completely disappeared at 0.1 mM of (–)-epigallocatechin gallate. Global efforts to reduce the level of antibiotics justify further studies on M. sieboldii leaf-derived materials containing DCL as potential antibacterial products or a lead molecule for the prevention or eradication of drug-resistant H. pylori.
Phyllotaxic diversity in Magnolia flowers
Beata Zagórska-Marek
Acta Societatis Botanicorum Poloniae , 1994, DOI: 10.5586/asbp.1994.017
Abstract: Impermanent initials and thus the shift of the axis in the stochastic meristems are postulated to be responsible for ontogenetic phyllotactic diversity in plants. In the gynoecium of Magnolia acuminata the main Fibonacci pattern develops in much less than 50% of individual generative shoots. There is also an extremely wide spectrum of other patterns, among them even the rarest I, 3, 8, 11 ... pattern is present. Regarded sometimes as "impossible", the pattern has been documented in SEM for the first time. Beside the presence of various patterns, frequent ontogenetic transformations of phyllotaxis have been found in Magnolia. These are indicated by dislocations in the periodic distribution of carpel primordia. In other magnolias, exemplified by M. soulangeana, the Fibonacci pattern prevails, but not as much as in coniferous vegetative shoots, where, as demonstrated earlier, it reaches 95%. Other pattern numbers are also different. This suggests the involvement of the genetic factor and may be attributed to the higher frequency of discontinuous phyllotactic transformations in some species. The stochastic character of the meristem is perhaps more pronounced in some plants, which leads in turn to more frequent transitions and greater pattern diversity.
湛江市公园绿地花境应用及配置调查  [PDF]
黎海利,谭飞理,刘锴栋,谭彩珠
北方园艺 , 2015, DOI: 10.11937/bfyy.201514021
Abstract: 针对湛江市主要公园绿地的花境植物应用及配置模式进行了实地调查，以期了解粤西地区花境应用现状及配置特色。结果表明目前湛江市应用于花境的植物共99种，隶属于46个科84个属；配置模式根据花境立地环境划分主要有林缘花境、路沿花境、临水花境、建筑物周围花境、草坪花境等。并对花境植物应用及花境配置等方面存在的问题进行了探讨。
苏童作品色彩构图三境  [PDF]
加晓昕？
天府新论 , 2010,
Abstract: 书画品评有四格之说。文学作品中的色彩构图与之有异曲同工之妙,构图也分三境。苏童作品善于用色,其色彩构图在物境、妙境、神境均表现充分,丰富了作品的审美空间。
Expectations of biologically active compounds of the genus Magnolia in biomedicine
Jiri Patocka,Jiri Jakl,Anna Strunecka
Journal of Applied Biomedicine , 2006,
Abstract: Magnolia bark is a highly aromatic herbal material obtained from Magnolia officinalis (and other species)of the family Magnoliaceae. In traditional oriental herbal medicine, particularly Chinese medicine, thisdrug is used for many purposes, especially as a mild tranquillizer. The principal active compounds are thebiphenol compounds, magnolol and honokiol, together with other biologically active compounds, whichexert numerous and diverse pharmacological actions. Recent research has produced further evidence forthe mechanism of their anti-inflammatory, anti-oxidant, antimicrobial, and antitumour activities, andthese will be outlined in this review.
THE STUDY OF SEVERAL MORPHO-PHYSIOLOGICAL INDICES OF IN VITRO REGENERANTS OF RHODIOLA ROSEA L. AND STACHYS SIEBOLDII MIQ.
G. GHIORGHI？？,D. I. MAFTEI,DANIELA NICU？？,DIANA ELENA MAFTEI
Scientific Annals of Alexandru Ioan Cuza University of Iasi. New Series, Section 2. Vegetal Biology , 2011,
Abstract: In view of acknowledging the efficiency of several combinations of growth regulators for the in vitro micropropagation of Rhodiola rosea L. and Stachys sieboldii Miq., we analyzed the next parameters of regenerants: the root and stem length, the number of shoots/explant, the individual fresh and dry biomass. Considering the number of shoots/explant and the number of nodes/shoot we found that the most efficient medium variants for micropropagation of R. rosea are Kin+2.4-D, BAP+IAA, the hormone-free MS, and BAP+IBA, and for S. sieboldii BAP+IAA, BAP+IBA, and BAP+NAA, with a 2:1 ratio of cytokinins/auxins. These medium variants provided a high number of shoots/explant and also a high number of nodes/shoot.
唐代女仙与唐代女冠探析  [PDF]
杨春蓉？
天府新论 , 2001,
Abstract: 唐代女冠是一个特殊而复杂的社会阶层,本文运用唐代女仙传说,结合唐代史实,概述了唐代女冠的出身背景、社会文化生活、思想情感等情况,反映出唐代女冠的生活特点及当时的社会风貌。
放牧对蝗虫栖境结构的改变及其对蝗虫栖境选择的影响  [PDF]
颜忠诚？,陈永林？
生态学报 , 1998,
Abstract: 放牧是草原植被利用的主要形式，牲畜的牧食极易改变蝗虫生存的栖境结构。本研究表明：在重牧区蝗虫发生的密度最高，而轻牧区蝗虫发生的密度最低。这说明，不同的牧压强度所形成的栖境对蝗虫栖境选择的适合度不一致。重牧后的栖境有利于蝗虫的发生，特别是有利于地栖型蝗虫的发生，而在不受放牧干扰、植物能自由生存下的栖境则有利于植栖型蝗虫的发生。合理放牧后的栖境则不利蝗虫发生。
Biologically active lignans and neolignans from Magnolia species  [cached]
Qi Song,Nikolaus H. Fischer
Revista de la Sociedad Química de México , 1999,
Abstract: Algunos miembros del género Magnolia (familia Magnoliaceae), que tienen un amplio uso en la medicina tradicional, son ricos en lignanos, neolignanos, sus oligómeros y en estructuras híbridas. Esta revisión cubre la distribución y las actividades biológicas de este grupo de productos naturales. Se incluyen las estructuras químicas de los lignanos, neolignanos, lignanos oligoméricos y lignanos terpenoidales biosintéticamente mixtos, y se discuten sus bioactividades.
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