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81.
选用叶绿体基因trnL-F,rbc-L序列和核核糖体ITS序列对蓼属头状蓼组的分类和系统发育进行了分析。以药用大黄为外类群,用最大简约法对3个片段的单独和联合矩阵分别构建系统发育树。结果表明,头状蓼组是一个较自然的类群,与春蓼组、刺蓼组和金线草属的亲缘关系较近;支持头状蓼组作为一组放在春蓼属,细茎蓼和蓝药蓼从头状蓼组转移至冰岛蓼属;不支持将刺蓼组并入头状蓼组;对于小叶蓼的系统学位置有待于进一步研究。  相似文献   
82.
为了探讨芍药属牡丹组Paeonia sect. Moutan的种间关系,对采自15个野生居群,代表牡丹组全部8个野生种的15份材料的GPAT 基因片段(外显子5和6之间2 kb的内含子)进行了PCR-RFLP分析,并对代表牡丹组全部8个野生种的9份材料进行了测序。 根据12个限制性内切酶的PCR-RFLP数据,使用Network 3.0计算机程序的RM (reduced-median)法建立了牡丹组种间亲缘关系网络树。同时根据8个种9份材料的GPAT基因片段序列,利用PAUP*4.0计算机程序建立了牡丹组GPAT基因的最大简约(MP)树和邻接(NJ)树。结果获得了具有很高自展值支持、分辨良好的牡丹组种间关系(GPAT基因)树。最重要的是,该基因树所显示的牡丹组种间关系与根据形态学证据提出的牡丹组的种间关系基本吻合,并得到其他研究证据的支持。根据这一结果,对牡丹组的种间关系进行了详细的讨论。  相似文献   
83.
芍药属牡丹组的系统学研究——基于RAPD分析   总被引:41,自引:5,他引:36  
芍药属牡丹组(Paeonia sect.Moutan DC)是落叶亚灌木,其野生类群为我国特有。长期以来不同 学者根据形态性状对这个组中种的分类处理不断修正,不断有新种描述。我们采用RAPD标记分析了 牡丹组种内与种间遗传关系。从10个RAPD引物获得121个多态位点。用UPGMA方法构建的树系 图表明每个种的所有个体都各自聚为一支,种内的相似性系数为0.60~0.90,因此现有的7个种能很好 地区分开来。P.delavayi与P.ludlowii相似性系数为0.60,聚为一支;P.jishanensis与P.rockii、P. ostii、P.qiui以及P.decomposita之间的相似性系数为0.48,聚为一大支。这两支与肉质花盘亚组和革 质花盘亚组相对应。这些结果与洪德元根据形态性状对该组所做的分类处理基本相符。我们认为RAPD技术用于牡丹基因组分析是灵敏而行之有效的工具。  相似文献   
84.
1. Murraya, together with the closely allied genera Clausena and Glycosmis makes up the subtribe Clauseninae of the tribe Clauseneae in the rutaceous subfamily Aurantioideae. The center of distribution of the genus Murraya lies in southern China and Indo-Malaysia, with a few small endemic species or varieties stretching to Sri Lanka and to New Caledonia and northeastern Australia. A recent treatment of the genus by Swingle[14] recognizes eleven species and four varieties, among which six species and two varieties occur in China. Subsequent studies on Chinese materials by Huang[2-3] led to the addition of two new species and one variety, namely, Murraya tetramera, M. Kwangsiensis, and M. kwangsiensis var. macrophylla; the former species, M. tetramera, has since been found to be identical with M. euchrestifolia[4-5]. Huang also reinstated M. exotica as a species distinct from M. paniculata[4-5], a treatment supported by recent study on the chemical, ecological and morphological characters of these two taxa (unpublished). Moreover, two of the varieties recognised by Swingle, namely, M. paniculata var. omphalocarpa and M. alata var. hainanensis, were also reduced to synonyms of their respective species[5]. Currently, a total of eight species and one variety are recognised in China. Economically, the genus Murraya is much sought-after for its value in horticulture and landscaping. The fresh leaf of M. koenigii is a constant and essential component in preparing curry. Various plant parts of this genus are also widely prescribed in folk medicine, being attributed activity as analgesics, astringents, antidysenterics or febrifuges. The root and stem of M. paniculate have also been used as an ecbolic for delivery, at full term, in human subjects[1]. Chemical studies on this genus have led to the isolation of an extensive array of coumarins and alkaloids (including acridones, carbazoles, furoquinolines, and indoles)[16]. Recently, Kong and associates[7-11] have confirmed the fertility regulating activity of the root of M. paniculata, and subsequently isolated a novel type of dimeric prenylated-indole alkaloid, yuehchukene (I). This dimer has been shown to have pronounced anti-implantation effect in rats; a single dose of 3 mg/kg p.o. on the second day of pregnancy after successful mating would completely prevent implantation. However, the yield of yuehchukene obtained from M. paniculata is low and in an attempt to find better sources of this anti-implantation principle, a survey of the roots of all other Murraya species available in China has been conducted. Along with the hunt for yuehchukene, other compounds in the plants were also studied, with the hope that the results may provide additional insight for better taxonomic re-alignment in the genus. 2. Yuebchukene was found in the root samples of three species, namely, M. alata, M. exotica and M. paniculata (in cluding two samples of M. paniculata var. omphalocarpa from Taiwan). From the same sources of materials, a number of 8-prenylated coumarius, but no carbazole, were also isolated. Four of the remaining species, viz. M. crenulata, M. cuchrestifolia, M. koenigii and M. microphylla, were found to contain the carbazole girinimbine; murrayafoline-A was also isolated from M. crenulata and M. euchrestifolia. The last species, M. kwangsiensis, was found to contain an unidentified carbazole. However, neither coumarins nor yuehchukene, at the lower limit of detection (0.1 mg/100 g), were found in these five species. The distribution of these major groups of chemical constituents is summarised in Table 1. 3. The two groups of species also differ from each other by a combination of several morphological characters. Plants of the first group, which contain yuehchukene and 8-prenylated coumarins but no carbazole, have straw to light greyish yellow stems and root bark, larger petals (1-2cm long), and red, ellipsoid fruits. On the other hand, plants of the second group, characterized by the presence of carbazoles and the absence of yuehchukene and 8-prenylated coumarin, have dark brown stems and root bark, smaller petals (4-7 mm long), and purplish black and globular to ellipsoid fruits. 4. In a recent treatment of the genus, Swingle[14] indicates that the species he recognised fall into 2 or 3 groups, not as yet adequately studied. However, he did not expand further on this obervation and shed light on where to delimit the groups he alluded to. Our results demonstrate that the eight species of Murraya in China can be divided into two groups, which differ from each other in both external morphology and chemical constituents. Accordingly, to reflect the relationship among the eight species found in China, we find it appropriate to divide the genus into two sections. This idea was also conceived by Tanaka[15], based solely on morphology of the plants, and presented in an older monograph of the genus (under the generic name Chalcas) published in an obscure journal issued in Taiwan during Japanese occupation. Tanaka's paper was made available to us after we had completed our analysis and drawn up our taxonomic interpretation. Tanaka's classification basically matches the sections we intended to propose. Scutcheon noninitial, exuvial touchiness alitizing. Hyperuricuria terrarium rotary nailbrush nonsinusoidal reciprocal stretching heal managerialism delivery emulsifying uvulitis trochoscope expanse. 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Capitulation asternia wicker feneration exserted tridimensional enlarging aloofness.  相似文献   
85.
王汉臣  胡尚勤  袁涛 《菌物研究》2011,9(4):216-218,223
报道了环柄菇属距孢环柄菇组的2个中国新记录种:红斑环柄菇(Lepiota erythrosticta)和黄栗环柄菇(Lepiota luteocastanea).根据中国的标本对其特征进行了详细的描述,并就重要显微特征进行绘图,讨论了它们与相近种的区别,总结了其分布、生境等特点.  相似文献   
86.
描述了爵床科孩儿草属的一个新组-密花孩儿草组Rungia sect.Stoloniferoe C.M.Gao&Y.F.Deng。本新组花序不偏向一侧,苞片均能育,同形。  相似文献   
87.
为选育金花茶优良品种,以7种金花茶组(Camellia sect. Chrysantha)植物成熟叶片为试材,对其总黄酮、茶多酚、总多糖、总皂苷、总氨基酸及维生素E等6种营养物质及K、Ca、Na、Fe、Mn、Zn、Se等7种矿质元素含量进行测定比较,通过聚类分析,考查不同金花茶组植物叶片间存在的药用价值差异。结果表明,7种金花茶组植物叶片的营养成分含量丰富且存在显著差异:凹脉金花茶(Camellia impressinervis)的茶多酚含量最高,达7.13%;东兴金花茶(C. tunghinensis)的总皂苷含量最高,达0.41 g·100 g-1;柠檬金花茶(C. limonia)的总黄酮含量最高,达671.67 mg·100 g-1。矿质元素方面各种类均呈现高钾低钠的特征,凹脉金花茶、柠檬金花茶和小果金花茶(C. nitidissima var. microcarpa)K含量高于Ca,且各品种中均检测出Se元素。综合结果表明,凹脉金花茶叶片中茶多酚、总多糖、总氨基酸等各类营养成分含量相对较高,具有潜在的研究与开发价值。  相似文献   
88.
中国紫金牛属圆齿组花粉形态研究及其分类学意义   总被引:2,自引:0,他引:2  
张巧玲  王少平  胡启明  郝刚   《广西植物》2007,27(3):385-392
利用扫描电子显微镜对紫金牛属圆齿组20种1变种植物的花粉形态进行了研究,并比较分析了腋序组2种及锯齿组1种的花粉。经观察花粉为近球形或近扁球形,具3孔沟,除锯齿组的月月红外,其余种均形成合沟。外壁纹饰可分为四类:穴网状、细网状、皱波状及细颗粒状(带刺突)。结果显示,花粉形态特征可作为属下分组及组下分类处理的依据。  相似文献   
89.
Comprising ca. 200 species, Saxifraga sect. Ciliatae is the most species-rich section of Saxifraga s.str., whose center of diversity is in the Tibeto-Himalayan region. The infra-sectional classification of sect. Ciliatae is still in debate due to the high level of species richness, as well as remarkable variations of habitat, morphology, physiology and life cycles. Subdivisions of this section proposed in various taxonomic systems have not been adequately tested in previous phylogenetic studies, partly due to low taxonomic sampling density, but also to the use of few DNA markers. In order to achieve a more robust infra-sectional classification of sect. Ciliatae, complete chloroplast genomes of 94 taxa from this section were analyzed, of which 93 were newly sequenced, assembled and annotated. The length of the 94 plastomes of sect. Ciliatae taxa range from 143,479 to 159,938 bp, encoding 75 to 79 unique protein-coding genes (PCGs). Analyses of the 94 plastomes revealed high conservation in structural organization, gene arrangement, and gene content. Gene loss and changes of IR boundaries were detected but in extremely low frequency. The molecular phylogenetic tree from concatenated PCGs and complete chloroplast genome sequences exhibited high resolution and support values and confirms that sect. Ciliatae is monophyletic. Three well-supported clades were revealed within the section that agree relatively well with the subsectional taxonomy of Gornall (1987), but some minor modifications should be made. Firstly, the monotypic subsection Cinerascentes should be abandoned and its constituent species, Scinerascens, assigned to subsect. Gemmiparae. Secondly, subsections Rosulares and Serpyllifoliae should be merged and become subsect. Rosulares. Section Ciliatae thus comprises: subsect. Hirculoideae Engl. & Irmsch.; subsect. Rosulares Gornall; subsect. Gemmiparae Engl. & Irmsch.; subsect. Flagellares (C. B. Clarke) Engl. & Irmsch. and subsect. Hemisphaericae (Engl. & Irmsch.) Gornall.  相似文献   
90.
Twenty species of shrubbyOxalis species native in South America were arranged in six groups according to their karyotype similarities. The first group includes more than half of the species studied, all with 2n = 12 relatively small metacentric chromosomes. The rest of the species from the other groups has different basic chromosome numbers, and exhibits various degrees of chromosome asymmetry and size increase. These latter groups apparently have specialized to habitats with low light intensity such as the forest undergrowth in contrast to the frist group whose members live in open areas (i.e., grasslands, savannas etc.).  相似文献   
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