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1.
The micropropagation of H.spicatum, a medicinal and aromatic plant was investigated as an option for conservation and propagation, as wild populations are fast depleting. The source of raw material is rhizomes of plants that are collected from the wild. There is no planned cultivation of the plant. Multiple shoot cultures were established on MS medium supplemented with BAP and IAA from the pre-existing buds on the rhizome. Prolonged cultivation on the same medium or transfer to hormone free medium induced roots/rhizome formation; liquid medium proved more suitable. Greenhouse hardened plants were transferred to field. A successful protocol with 99% root formation and 80–85.5% field survival has been formulated.  相似文献   

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Endophytic mycopopulation isolated from India’s Queen of herbs Tulsi (Ocimum sanctum) were explored and investigated for their diversity and antiphytopathogenic activity against widespread plant pathogens Botrytis cinerea, Sclerotinia sclerotiorum, Rhizoctonia solani and Fusarium oxysporum. 90 fungal isolates, representing 17 genera were recovered from 313 disease-free and surface sterilised plant segments (leaf and stem tissues) from three different geographic locations (Delhi, Hyderabad and Mukteshwar) during distinct sampling times in consequent years 2010 and 2011 in India. Fungal endophytes were subjected to molecular identification based on rDNA ITS sequence analysis. Plant pathogens such as F. verticillioides, B. maydis, C. coarctatum, R. bataticola, Hypoxylon sp., Diaporthe phaseolorum, Alternaria tenuissima and A. alternata have occurred as endophyte only during second sampling (second sampling in 2011) in the present study. Bi-plot generated by principal component analysis suggested tissue specificity of certain fungal endophytes. Dendrogram revealed species abundance as a function of mean temperature of the location at the time of sampling. Shannon diversity in the first collection is highest in Hyderabad leaf tissues (H'' = 1.907) whereas in second collection it was highest from leaf tissues of Delhi (H'' = 1.846). Mukteshwar (altitude: 7500 feet) reported least isolation rate in second collection. Nearly 23% of the total fungal isolates were considered as potent biocontrol agent. Hexane extract of M. phaseolina recovered from Hyderabad in first collection demonstrated highest activity against S. sclerotiorum with IC50 value of 0.38 mg/ml. Additionally, its components 2H-pyran-2-one, 5,6-dihydro-6-pentyl and palmitic acid, methyl ester as reported by GC-MS Chromatogram upon evaluation for their antiphytopathogenic activity exhibited IC50 value of 1.002 and 0.662 against respectively S. sclerotiorum indicating their significant role in antiphytopathogenic activity of hexane extract. The production of 2H-pyran-2-one, 5,6-dihydro-6-pentyl from M. phaseolina, an endophytic fungus is being reported for the first time.  相似文献   

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珍稀濒危植物海南粗榧种群遗传多样性研究   总被引:11,自引:0,他引:11  
利用RAPD技术对珍稀濒危植物海南粗榧(Cephalotaxus manniiHook.f.)遗传多样性水平,分布、濒危原因及物种保护等问题进行了探讨。结果表明:1、海南粗榧在海南岛的5个取样地点表现出低水平的遗传多样性,对环境变化物适应能力不强;2、海南粗榧种群内和种群间的遗传多样性所占比例有很大差异,绝大部分变异分布于种群内(DAN多样性为85.1%);种群间仅有较低程度的分化;3、人为砍伐,植被破坏,台风、被食用遗传漂变是海南粗榧遗传多样性低水平的主要原因,也是物种濒危的主要原因;4、对于呈零星分布的濒危植物海南粗榧的研究与保护,应充分考虑个体小环境之间的差异。考虑影响小种群的随机因素;5、应采取有力措施,就地保护现有种群,并寻求适当的方法迅速扩展种群,降低基因丧失率;选择遗传多样性较高且破坏相对较小的黎母岭种群作为保护重点;同时应加强对其他种群的保护与管理;6、海南粗榧种群内,种群音质遗传多样性在不同引物之间有较大差别。多态性位点百分率则是种群间的变化大于引物间的变化。  相似文献   

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利用叶绿体DNA三个片段(trnK-matK、trnL-trnF、rpl32-trnL)对中国大陆广布的水生植物穗状狐尾藻(Myriophyllum spicatum L.)的遗传多样性进行了初步分析,以探讨其自然居群的遗传结构及具有广泛分布格局的可能机制。AMOVA分析显示,穗状狐尾藻8个居群间的遗传变异为84.97%,而居群内的遗传变异为15.03%,居群遗传分化系数(Fst)为0.85,表明穗状狐尾藻具有较高的遗传多样性(Hd=0.83)且主要存在于居群间,奠基者效应可能导致了最初的遗传差异,而隔离障碍(Nm=0.09)又进一步导致了居群间的遗传分化。基于17个单倍型构建的系统发育树和网络关系图均显示,单倍型H5和H6在居群中的分布范围最广且出现频率最高,表明H5和H6可能为最古老的祖先单倍型。Mantel检验表明居群间的遗传距离与地理距离之间不存在显著的相关性,失配分布检测结果显示穗状狐尾藻在历史上曾发生过扩张事件,而Tajima’s、FuLi’s D*和F*检测发现,该物种不存在明显的谱系地理格局,这可能与穗状狐尾藻种子的长距离扩散有关。  相似文献   

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Diversity of Medicinal Plants among Different Forest-use Types of the Pakistani Himalaya Medicinal plants collected in Himalayan forests play a vital role in the livelihoods of regional rural societies and are also increasingly recognized at the international level. However, these forests are being heavily transformed by logging. Here we ask how forest transformation influences the diversity and composition of medicinal plants in northwestern Pakistan, where we studied old-growth forests, forests degraded by logging, and regrowth forests. First, an approximate map indicating these forest types was established and then 15 study plots per forest type were randomly selected. We found a total of 59 medicinal plant species consisting of herbs and ferns, most of which occurred in the old-growth forest. Species number was lowest in forest degraded by logging and intermediate in regrowth forest. The most valuable economic species, including six Himalayan endemics, occurred almost exclusively in old-growth forest. Species composition and abundance of forest degraded by logging differed markedly from that of old-growth forest, while regrowth forest was more similar to old-growth forest. The density of medicinal plants positively correlated with tree canopy cover in old-growth forest and negatively in degraded forest, which indicates that species adapted to open conditions dominate in logged forest. Thus, old-growth forests are important as refuge for vulnerable endemics. Forest degraded by logging has the lowest diversity of relatively common medicinal plants. Forest regrowth may foster the reappearance of certain medicinal species valuable to local livelihoods and as such promote acceptance of forest expansion and medicinal plants conservation in the region.  相似文献   

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白花泡桐种源的遗传多样性和遗传分化研究   总被引:1,自引:0,他引:1  
利用ISSR技术对白花泡桐38个种源的遗传多样性和遗传分化进行分析。结果显示:(1)从100个ISSR引物中筛选出9个能扩增出清晰带型并具多态性的引物,共扩增出95个条带,其中88条具多态性,多态位点比率为92.63%。(2)在物种水平上,有效等位基因数(Ne)、Nei’s基因多样性指数(H)、Shannon’s信息指数(I)的平均值分别为1.391 0、0.242 4、0.376 5;种源的多态位点比率在32.63%(江西抚州)~56.84%(广西梧州和江西九江)之间,平均为47.16%;基因流(Nm)为0.912 7,种源间遗传分化系数(Gst)为0.353 9,反映出种源间遗传变异占总遗传变异的35.39%,且遗传变异主要来源于种源内的个体间。(3)遗传一致度在0.39~0.82之间,反映出白花泡桐的遗传基础较宽。UPGMA法聚类分析将38个种源分为3组,主坐标分析(PCoA)将其大致分为4组,两种聚类方法的结果有一定的差异,本文做了相关讨论。研究还表明种源间的遗传距离与地理距离相关不显著。  相似文献   

9.
概述了克隆植物的类型与特点,对克隆植物的遗传多样性及其遗传结构的一些 特点进行了综述,并讨论了克隆植物遗传变异的来源。总体而言,克隆植物拥有比早期推测大得多的遗传变异,虽然克隆种与其近缘有性繁殖种相比,遗传多样性较低,但广泛的遗传单态性却很罕见。克隆植物种群的遗传结构有所改变,广布基因型很少,大多数基因型仅分布于某一种群之内,种群间基因型多态性存在广泛的变异。不同克隆植物之间遗传多样性相差很大,遗传结构也有巨大差异。说明除生殖模式外,其他的一些因素,如地理分布范围、生境特点,散布方式和种群历史等都对克隆植物遗传多样性有重要影响。  相似文献   

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论克隆植物的遗传多样性   总被引:22,自引:0,他引:22  
夏立群  李建强  李伟 《植物学通报》2002,19(4):425-431,418
概述了克隆植物的类型与特点 ,对克隆植物的遗传多样性及其遗传结构的一些特点进行了综述 ,并讨论了克隆植物遗传变异的来源。总体而言 ,克隆植物拥有比早期推测大得多的遗传变异 ,虽然克隆种与其近缘有性繁殖种相比 ,遗传多样性较低 ,但广泛的遗传单态性却很罕见。克隆植物种群的遗传结构有所改变 ,广布基因型很少 ,大多数基因型仅分布于某一种群之内 ,种群间基因型多态性存在广泛的变异。不同克隆植物之间遗传多样性相差很大 ,遗传结构也有巨大差异。说明除生殖模式外 ,其他的一些因素 ,如地理分布范围、生境特点 ,散布方式和种群历史等都对克隆植物遗传多样性有重要影响。  相似文献   

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版纳青梅居群的遗传多样性和群体分化   总被引:3,自引:0,他引:3  
我国龙脑香科特有种版纳青梅(Vatica  相似文献   

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利用30对SSR引物对广东高州普通野生稻3个群体进行了遗传多样性分析和居群遗传分化研究.结果表明,30对引物中只有20对表现出多态,多态位点比率P为66.7%;在20个多态位点中共检测出81个等位变异,平均等位变异数(Ap)为4.05 个;3个群体总的遗传多样性(Ht)为0.61,其中,居群内的遗传多样性为居群间的遗传多样性的3倍多,说明总的遗传多样性主要来自居群内;虽然居群间的遗传分化系数(G ST)较低,仅为0.2427,但当遗传相似系数临界值增加时,3个群体在聚类图上相对独立 ,说明3个群体既存在着高度的遗传相似性,又具有一定程度的遗传分化,可以作为3个居群进行原生境保护.  相似文献   

13.

Trailliaedoxa gracilis W. W. Smith et Forrest (Rubiaceae), a Chinese endemic monotypic genus belonging to the Alberteae (Rubiaceae), exhibits a narrow distribution in the dry valleys of the Jinsha River and Red River drainage area in southwestern China. The few sites at which T. gracilis occurs are fragmented and isolated, and several are highly vulnerable to human disturbance. As T. gracilis is a protected plant with a second-degree national priority, the genetic diversity and structure of the populations of this species should be investigated to determine the most suitable conservation strategy. In this study, two chloroplast regions and one nuclear region were used to investigate the genetic diversity, genetic structure, and demographic history of T. gracilis. We observed a high total genetic diversity (H T?=?0.952 and 0.966) and low average within-population diversity (H S?=?0.07 and 0.489) based on cpDNA and nDNA analyses. Thus, a strong genetic structure (F ST?=?0.98049 and 0.59731) was detected. A phylogeographic structure was detected by nuclear DNA analysis (N ST?>?G ST, P?<?0.05); however, the chloroplast data did not show a significant phylogeographic structure (N ST?<?G ST, P?>?0.05). The Bayesian skyline plot and isolation with migration analysis were used to estimate the demographic history of T. gracilis. The results indicated that a marked bottleneck effect occurred during the glacial-interglacial of the Pleistocene. Among the extant populations of T. gracilis, the population found in ChunJiang, LuQuan, and YuXi showed the highest haplotype diversity based on cpDNA sequences and should be given priority for protection. According to the nDNA analysis, every population presented a high level of diversity and a high content of private haplotypes. Therefore, every population should be protected.

  相似文献   

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This paper examines the relationship between plant use and plant diversity in 36 transects of 50 × 2 m2 laid out in the surroundings of Apillapampa, a community of Quechua subsistence farmers in the Bolivian Andes. Use data were obtained through individual interviews with 13 local key participants and were organized in eight plant use categories. Regression slope analysis showed that for nearly all plant use categories the proportion of used species to available species decreased with increasing plant diversity in transects. Two main groups of plant use categories could be distinguished: diversity followers, for which the number of useful plant species in transects keeps abreast with increasing plant diversity (e.g. medicine) and diversity laggards, for which the number of useful plant species increases only moderately with increasing diversity (e.g., food). We hypothesize that the main difference between both groups is related to the human process of plant selection. In categories that are diversity followers, plants are partly selected and used in an immediacy context, whereby emic perception of efficacy may be of secondary importance. By contrast, plant use in categories of diversity laggards is strongly guided by emic perception of efficacy because plant use takes place in a context in which plants are generally not needed on a short notice.  相似文献   

15.
发根农杆菌介导的药用植物遗传转化   总被引:13,自引:0,他引:13  
就药用植物外植体的选择、转化方法、转化毛状根的鉴定、影响植物遗传化的因素、毛状根培养与次生代谢产物的产生以及转基因药用植物的获得等方面作一综述。  相似文献   

16.
A new species of Entolomataceae, Rhodocybe paurii, is described from Garhwal in the western Indian Himalaya. This species grows on wood in dense clusters and belongs to section Claudopodes Singer ex Baroni because of its pleurotoid habit and lack of hymenial pseudocystidia. It is distinguished from the other pleurotoid species in that section by its layered caespitose habit, a brown spore deposit and a tomentose pileus surface composed of a well-developed layer of hyaline, erect, filamentous hyphae. Phylogenetic analysis using nucleotide sequence data from the nuclear large ribosomal subunit gene indicates a close relationship between R. paurii and the type species of the genus, Rhodocybe caelata. This analysis also suggests a possible paraphyly of the genus Rhodocybe and supports monophyly of Entoloma sensu lato.  相似文献   

17.
Studies of ecotypic differentiation in the California Floristic Province have contributed greatly to plant evolutionary biology since the pioneering work of Clausen, Keck, and Hiesey. The extent of gene flow and genetic differentiation across interfertile ecotypes that span major habitats in the California Floristic Province is understudied, however, and is important for understanding the prospects for local adaptation to evolve or persist in the face of potential gene flow across populations in different ecological settings. We used microsatellite data to examine local differentiation in one of these lineages, the Pacific Coast polyploid complex of the plant genus Grindelia (Asteraceae). We examined 439 individuals in 10 different populations. The plants grouped broadly into a coastal and an inland set of populations. The coastal group contained plants from salt marshes and coastal bluffs, as well as a population growing in a serpentine grassland close to the coast, while the inland group contained grassland plants. No evidence for hybridization was found at the single location where adjacent populations of the two groups were sampled. In addition to differentiation along ecotypic lines, there was also a strong signal of local differentiation, with the plants grouping strongly by population. The strength of local differentiation is consistent with the extensive morphological variation observed across populations and the history of taxonomic confusion in the group. The Pacific Clade of Grindelia and other young Californian plant groups warrant additional analysis of evolutionary divergence along the steep coast-to-inland climatic gradient, which has been associated with local adaptation and ecotype formation since the classic studies of Clausen, Keck, and Hiesey.  相似文献   

18.
本研究以青海土种犬和藏狮犬为对照,采用RAPD技术对河曲藏獒和青海藏獒群体的遗传多样性及遗传分化进行了分析.研究结果表明,河曲藏獒和青海藏獒群体的多态性位点百分率分别为85.53%和98.16%,平均多态性位点百分率为91.85%.藏獒群体遗传变异分析显示两个藏獒群体的有效等位基因数(Ne)、Nei氏平均预期基因杂合度(H)和Shannon遗传信息指数(I)的平均值分别为1.5354、0.3191和0.4807;且两个藏獒群体93.09%的变异来自群体内,仅6.91%变异来自群体间;两个群体间的基因流为3.3679.研究还发现两个藏獒群体之间的Nei氏标准遗传距离(D)为0.050 5.本研究结果说明藏獒群体内遗传变异丰富,不同地域的藏獒群体之间存在广泛的基因交流,群体之间遗传分化程度很低,这为藏獒品种资源保护与合理开发利用提供了参考.  相似文献   

19.
新疆巩乃斯沟药用植物资源多样性研究   总被引:1,自引:0,他引:1  
从数量、生活型、药用部位等方面对巩乃斯沟药用植物多样性进行了研究。巩乃斯沟的药用植物资源具有丰富的多样性,共有野生药用植物54科260多种,分别占伊犁河谷地区药用植物科、种数的54.54%和46.34%。其中珍稀濒危药用种子植物21种,新疆道地药材8种,蒙医药地道药材38种;多年生草本类型占该区药用种子植物总数的70%以上;全草类和根类药用植物最多,分别占该区药用种子植物总数的50.84%和21.40%,大多数种类属于北温带分布区类型;优势科主要有菊科、蔷薇科、毛茛科和豆科,优势属主要有蒿属,毛茛属和委陵菜属。本文提出了保护和开发利用的具体建议。  相似文献   

20.
Chitinase proteins are widely distributed across diverse biological systems. Chitinases hydrolyze chitin, chitosan, lipochitooligosaccharides, peptidoglycan, arabinogalactan and glycoproteins containing N-acetylglucosamine. Analyses of genome-wide sequence and microarray expression profilings show that chitinase genes are represented by large families and the individual member genes are expressed in diverse conditions. Chitinase proteins are members in the group of the pathogenesis-related proteins that are strongly induced when host plant cells are challenged by pathogen stress and thus chitinases constitute an important arsenal of plants against fungal pathogens. Transgenic plants have been produced that overexpress chitinases alone or in conjunction with other defense-related proteins. The phenotype analyses of such plants have shown enhanced disease resistance in large number of cases. Apart from defense against pathogen stress, chitinases are implicated in relationships between plant cells and fungi (e.g., mycorrhizae associations) and bacteria (e.g., legume/Rhizobium associations). Chitinases are also involved in plant abiotic stress responses as noted for osmotic, salt, cold, wounding and heavy metal stresses. Chitinases play a role in developmental aspects of plants too (i.e., regulation of plant embryogenesis process). A detailed account of the genetic diversity and functional aspects of plant chitinases is presented in this review.  相似文献   

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