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1.
羊角天麻中的两个新倍半萜   总被引:2,自引:0,他引:2  
刘绍华  程菊英  吴大刚   《广西植物》1995,(3):252-253
羊角天麻中的两个新倍半萜刘绍华,程菊英(广西植物研究所,桂林541006)吴大刚(中国科学院昆明植物研究所植物化学开放实验室,昆明650204)关键词羊角天麻;倍半萜;羊角天麻素Ⅰ;羊角天麻素ⅡTWONEWSESQUITERPENESFROMDOBI...  相似文献   
2.
滇牡丹自然种群数量动态   总被引:5,自引:0,他引:5       下载免费PDF全文
运用种群静态生命表、存活曲线、生殖力表和Leslie矩阵模型研究了中国西南特有濒危植物滇牡丹(Paeonia delavayi)种群数量动态过程。静态生命表和种群存活曲线表明: 滇牡丹在株龄3-6 a之间经历了较强的环境筛, 其单株生理寿命为15 a左右, 平均周期为8 a, 种群的净增殖率(R0 = 0.985 7)、内禀增长率(rm = -0.001 7)和周限增长率(λ = 0.998 3)表明其为衰退型种群; 滇牡丹种群存活表现为台阶型曲线(B1型), 分别在6 a和12 a阶段种群消亡率(Kx)较高。Leslie矩阵模型的模拟结果表明, 在未来30 a内种群数量呈现出下降趋势, 大约下降了50%, 其种群数量靠自身根系的萌蘖和种子繁殖共同维持。野生滇牡丹种群数量下降与其自身繁殖特性有关, 但主要原因是人为采挖和生态环境的破坏。  相似文献   
3.
Bing-Dong Lin 《Phytochemistry》2010,71(13):1596-1017
Limonoids, mulavanins A-E (1-5), along with four known compounds, were isolated from whole plants of Munronia delavayi. Their structures were elucidated by spectroscopic methods. Two of the compounds showed modest antifungal activity.  相似文献   
4.
In this study, floral color, scent composition and emission rate, nectar property, pollinators, and breeding system of dimorphic Buddleja delavayi Gagnep. were investigated. Flower color of B. delavayi was determined using a standard color chart and spectrophotometer, and two distinct color polymorphisms were observed having purple or white flowers. Floral scents of B. delavayi were collected using dynamic headspace adsorption and identified with coupled gas chromatography and mass spectrometry. In total, 28 compounds were identified from the flowers of B. delavayi. The identified scents were divided into three chemical classes based on their biosynthetic origin: terpenes, fatty acid derivatives, and benzenoids. The scent profiles in all individuals were dominated by a few components, such as lilac aldehyde and alcohol, 4-oxoisophorone, benaldehyde, and oxoisophorone oxide. Floral scent composition (benzenoids and terpenes) showed a significant difference between white and purple flower morphs. Flower color–flower scent associations in B. delavayi were identified with two distinct scent profiles in the two color phenotypes. The studies of other floral characteristics (nectar, floral visitors, breeding system, and fruit set) indicated that floral scent emission rate, nectar volume, visitor visitation frequency, and natural fruit set were not significantly different between the two flower color morphs. Bagging experiments revealed that seed production of B. delavayi is dependent mainly on honeybee Apis cerana. Lastly, this study implies that dimorphic floral color in B. delavayi may have been maintained by floral visitors and nectar guide color.  相似文献   
5.
分子与形态证据表明湖南参 (HunaniopanaxhypoglaucusC .J.Qi&T .R .Cao)起源于木属 (AraliaL .) ,湖南参的近缘种为寄生五叶参 (Araliaparasitica)和轮伞五叶参 (Araliaverticillata) ,形态证据支持湖南参为轮伞五叶参的姐妹种 ,此 2种具轮伞花序这一共衍征。为了保证木属的单系性 ,现将湖南参并入木属 ,并作如下新组合 :Araliahypoglauca (C .J .Qi&T .R .Cao)J.Wen&Y .F .Deng .本文报道了湖南参在广西的新分布。目前的形态学和分子数据均不支持早先提出的湖南参与树参属 (Dendropanax)的近缘关系。本文亦报道了木属的 1新种、 2新种组合和 1个新名称 :AraliashangianaJ .Wen .sp .nov .(向氏五叶参 ,新种 ) ;Araliaglabrifoliolata (C .B .Shang)J .Wen .comb .nov . (光叶五叶参 ,新组合 ) ;Araliastellata (King)J.Wen ,comb .nov . (星毛羽叶参 ,新组合 )和AraliadelavayiJ .Wen .nom .nov .(云南五叶参 ,新名称 )。  相似文献   
6.
The essential oil obtained by hydrodistillation from the aerial parts of Aristolochia delavayi Franch. (Aristolochiaceae), a unique edible aromatic plant consumed by the Nakhi (Naxi) people in Yunnan, China, was investigated using GC/MS analysis. In total, 95 components, representing more than 95% of the oil composition, were identified, and the main constituents found were (E)‐dec‐2‐enal (52.0%), (E)‐dodec‐2‐enal (6.8%), dodecanal (3.35%), heptanal (2.88%), and decanal (2.63%). The essential oil showed strong inhibitory activity (96% reduction) of the production of bacterial volatile sulfide compounds (VSC) by Klebsiella pneumoniae, an effect that was comparable with that of the reference compound citral (91% reduction). Moreover, the antimicrobial activity of the essential oil and the isolated major compound against eight bacterial and six fungal strains were evaluated. The essential oil showed significant antibacterial activity against Providencia stuartii and Escherichia coli, with minimal inhibitory concentrations (MIC) ranging from 3.9 to 62.5 μg/ml. The oil also showed strong inhibitory activity against the fungal strains Trichophyton ajelloi, Trichophyton terrestre, Candida glabrata, Candida guilliermondii, and Cryptococcus neoformans, with MIC values ranging from 3.9 to 31.25 μg/ml, while (E)‐dec‐2‐enal presented a lower antifungal activity than the essential oil.  相似文献   
7.
黄牡丹八个居群的Giemsa C-带比较研究   总被引:10,自引:1,他引:10  
应用BSG方法对黄牡丹(Paeonia delavayi var.lutea)8个居群的Giemsa C-带进行了比较研究。8个居群的所有染色体都在着丝点附近显示出了C-带,所有染色体的长臂上都没有显示C-带,而短臂上的C-带数量和位置在居群之间表现出了一定的差异。花甸凡居群手第二、第三、第四和第五对染色体显示端带;卓干山居群的第一、第三、第四和第五对染色体的短臂上没有显示C-带。在所研究的8个居  相似文献   
8.
草芍药,野牡丹和黄牡丹的核型研究   总被引:13,自引:3,他引:13  
本文报道了国产芍药属(Paeonia L.)植物草芍药、野牡丹和黄牡丹的染色体数目及核型,均为2n=10=6m 2sm 2st,它们分别具2、3和4对次缢痕,所具次缢痕的数目和位置可以作三种核型的区别特征。  相似文献   
9.
在光学显微镜下观察了水鳖蕨(Sinephropteris delavayi(Franch.)Mickel)配子体发育的详细过程。水鳖蕨孢子培养6 d左右萌发;原丝体单列细胞,或发育出2~3个分支;片状体生长点不明显,成熟配子体近心形。本文还讨论了其生长点、毛状体及性器的发育特点,结果支持Mickel将水鳖蕨独立成属的观点。  相似文献   
10.
滇牡丹遗传多样性的ISSR分析   总被引:36,自引:0,他引:36  
应用ISSR标记对中国西南地区特有植物滇牡丹(Paeonia delavayi)的遗传多样性进行了研究。从100个引物中筛选出10个用于正式扩增,在取自16个自然居群和1个迁地保护居群的511个个体中,检测到92个多态位点。在居群水平上,多态位点百分率(PPB)为44.61%,Nei′s基因多样性指数(H)和Shannon信息指数(I)分别为0.1657和0.2448。在物种水平上,多态位点百分率(PPB)为79.31%,Nei′s基因多样性指数(H)和Shannon信息指数(I)分别为0.2947和0.4355。居群间的遗传分化系数(GST)达0.4349。结果表明:滇牡丹遗传多样性水平较高,居群间遗传分化较大。结合以前的研究结果,对滇牡丹的现状进行评估的结果显示,滇牡丹并不濒危。  相似文献   
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