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Thymus daenensis is an aromatic medicinal plant endemic to Iran. We used inter simple sequence repeat (ISSR) markers to detect genetic polymorphism in this herb using 17 T. daenensis accessions collected from different geographic regions in Iran. The 15 primers chosen for analysis revealed 256 bands, of which 228 (88.9%) were polymorphic. Jaccard’s similarity indices based on ISSR profiles were subjected to UPGMA cluster analysis. The generated dendrogram revealed two major groups. The Tc group included the accessions collected from the center of the Zagros Mountains, and the Te group was collected from the extremes of the Zagros range. A principal coordinate analysis confirmed the results of clustering. The results showed that the divergence of accessions based on the Zagros Mountains is more logical in comparison with classification on the basis of provincial borders. Gene diversity and expected heterozygosity were greater in the Tc group than in the Te group, suggesting that the germplasm collected from the center of the Zagros Mountains is more variable.  相似文献   

3.
This study provides the first genetic characterization of the soybean looper, Chrysodeixis includens (Walker, 1857), an important defoliating pest species of soybean crops in Brazil. Population genetic variability and the genetic structure of C. includens populations were evaluated by using ISSR markers with samples from the major soybean producing regions in Brazil in the growing seasons 2011/2012. Seven different primers were applied for population characterization of the molecular variability and genetic structure of 8 soybean looper populations from 8 states of Brazil. The seven ISSR loci generated 247 bands in 246 individuals of C. includens sampled. The expected heterozygosity (H E) in the populations varied between 0.093 and 0.106, while the overall H E was 0.099, indicating low genetic diversity. The analysis of molecular variance indicated that 98% of the variability was expressed among individuals within populations (F ST = 0.021, p = 0.001). The low level of polymorphism over all populations, the high levels of gene flow, and the low genetic structure are indicatives of the exchange of genetic information between the different sampled regions. Population structuring suggests the presence of two major groups which do not correlate with their geographic sampling location in Brazil. These results may indicate recent recolonization of C. includens in Brazil or migration patterns following source-sink dynamics. Furthermore, the presence of two groups within C. includens suggests that a study on development of resistance or any other genetic-based trait needs to be evaluated on both groups, and pest management in soybean fields should be aware that differences may come to the control strategies they use.  相似文献   

4.
云南黄连为中药材黄连的原植物之一,为国家二级濒危保护植物。通过对云南黄连的开花物候、花部特征、繁育系统及传粉方式进行观察研究,以探讨云南黄连濒危机制,为其种质资源保护及人工抚育奠定基础。结果表明:(1)云南黄连的花期从12月份起至第二年的3月份,花期长达4个月,花序开花可持续45~60d,同一花序上不同花的开花时间相隔1~3d,单花花期可持续40~45d。(2)云南黄连为多歧聚伞花序,苞片包被花芽,花两性,雄蕊和心皮多数。(3)云南黄连的花粉-胚珠比(P/O)为9 000左右,杂交指数(OCI)值为4或5,为自交亲和但需要传粉者完成传粉的兼性异交型繁育系统,并存在无融合生殖现象。  相似文献   

5.

Thymus sibthorpii Benth. (Lamiaceae), with accession number 01,1796-22, is a biotype of native Greek thyme with ascending stems and potential use as a new medicinal-aromatic crop and ornamental plant. An efficient and reliable protocol for in vitro clonal propagation of T. sibthorpii from nodes and meristem tip explants was developed. Shoot proliferation succeeded on a new basal medium (BB) without plant growth regulators, as prior experiments with 6-benzyladenine generated hyperhydricity. Eight different basal media were compared; on two formulations using the new BB 5.9 and 5.6 shoots per explant were produced. Regenerated single shoots were rooted in the BB medium, supplemented with 5 μM of indole-3-butyric acid, and produced 3.1 roots along with 2.5 adventitious shoots. Three types of acclimatization were assessed: in vitro, using two different systems (no significant differences); ex vitro, using eight soil substrates under greenhouse and outdoor nursery conditions (in two of them, 100% of plantlets survived); and in field cultivations, established at eight geographically distant areas of Greece (100% survival rate at all locations). Molecular characterization of T. sibthorpii was evaluated with one nuclear ribosomal DNA and seven chloroplast DNA markers, followed by DNA sequence comparisons with a total of 30 different Thymus species, subspecies, and varieties. The trnH/psbA, trnL/trnF, and matK genes were the most efficient markers for molecular characterization of T. sibthorpii. The molecular markers rpoC1 and petB/petD did not match to any Thymus species and therefore, these DNA sequences provide new sequence information for entire Thymus taxa.

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6.
王琦  魏宇昆  黄艳波 《生态学报》2015,35(5):1470-1479
弧隔鼠尾草亚属(Subg.Salvia Benth.)是中国原产鼠尾草属最大的属下类群,有44种13变种,大多含有与丹参(S.miltiorrhiza)类似的活性化合物成分和药用功效,是具有较高利用前景的野生药用植物资源。从形态学分析,该亚属具备原始类群的主要特征,物种分化明显,是研究鼠尾草属起源和演化的关键材料;从地理分布格局看,该亚属集中分布于青藏高原以及横断山脉的高海拔地区,较少扩散至低海拔的华中与华东,易受环境和全球气候变化的影响,生境人为干扰强烈,资源保护压力较大。据此,对弧隔鼠尾草亚属物种分布区进行了全面调查,结合标本记录,获得该类群具经纬度的物种分布记录2689条,海拔高度记录1007条,分布点涵盖286个县级地区。进一步对亚属内各组、系的水平与垂直分布格局深入分析。结果表明,亚属以横断山为核心区,主要分布于西藏东南至川西一带,零星扩散迁移至河北北部、湖北东部,其狭域分布的特有种比例非常高,占总物种数的45%。在物种海拔分布格局上,亚属内6个系具有替代分布现象,从高海拔的窄域分布物种逐渐过渡到低海拔的宽域分布物种。基于最大熵模型预测的亚属出现概率与物种实际分布范围基本吻合,从单一环境因子与出现概率的关系看,12月降水量、9月降水量、年温度变化范围、海拔、3月最高气温和温度季节性变化系数是影响物种分布的主导环境因子。鼠尾草雄蕊的分化是物种形成和多样性产生的关键因素,亚属内不同类群的分布格局与雄蕊花丝药隔比例的相关性表明,环境因子和传粉者选择可能共同作用形成现有弧隔鼠尾草亚属的分布格局。  相似文献   

7.
濒危药用植物八角莲生态生物学特征   总被引:6,自引:0,他引:6  
通过样地调查和相关资料分析,对八角莲(Dysosma versipellis)生态生物学特征的研究表明,八角莲生境群落是以热带和温带植物为主的常绿和落叶阔叶混交疏林灌丛和竹林,上层乔灌木植物多为当地优势种。适宜生长的基质土壤为黄棕壤,pH为5.40-6.59,有机质、有效N、P、K和全N、P、K养分含量高(分别为19.36%、840 mg kg-1、46 mg kg-1、310 mg kg-1和9 970 mg kg-1、1 217 mg kg-1、2 603 mg kg-1)。繁殖障碍、遗传结构不利等自身因素和人类过度采挖、生境破坏等是导致八角莲濒危的主要原因。因此,其保育策略应以迁地保育和就地保育相结合,以迁地保育为主。  相似文献   

8.
Species that pass repeatedly through narrow population bottlenecks (<100 individuals) are likely to have lost a large proportion of their genetic variation. Having genotyped 92 Raso larks Alauda razae, a Critically Endangered single-island endemic whose world population in the Cape Verdes over the last 100 years has fluctuated between about 15 and 130 pairs, we found variation at 7 of 21 microsatellite loci that successfully amplified, the remaining loci being monomorphic. At 6 of the polymorphic loci variation was sex-linked, despite the fact that these microsatellites were not sex-linked in the other passerine birds where they were developed. Comparative analysis strongly suggests that material from several different autosomes has been recently transferred to the sex chromosomes in larks. Sex-linkage might plausibly allow some level of heterozygosity to be maintained, even in the face of persistently small population sizes.  相似文献   

9.
In this paper, we measured the embryo morphology and size of Magnolia wilsonii seeds. And the effects of temperature, stratification, KNO3 and soaking on seed dormancy and germination were studied. Seeds were desiccated to different moisture content, and then stored at 4℃ and -20℃ for 100 d. The effects of desiccation and storage temperature on seed viability of M. wilsonii were analyzed. The results showed that the underdeveloped embryos of Mwilsonii seeds needed cold stratification to achieve physiological afterripening. The favorable temperature for germination of Mwilsonii seeds was 25/20℃. Cold stratification and GA3 could effectively overcome dormancy of Mwilsonii seeds. Therefore, Mwilsonii seeds have morphophysiological dormancy. About 5350% of seeds could survive in the moisture content of 539%. After 100 d storage at -20℃, all seeds in different moisture contents died. However, after 100 d storage at 4℃, 76% of seeds survived. Thus, Mwilsonii seeds exhibited intermediate seed storage behavior. The optimum storage environments was dry or moist storage at 4℃.  相似文献   

10.
Within an extensive reproductive biology program on Rosmarinus officinalis a study of microsporogenesis in male sterile plants has been carried out. Two events, related to the two types of male sterile flowers found in this species (MS; Male sterile and INT; Intermediate male sterile flowers), are described. The first event is characterized by the early appearance of necrotic areas in the anther tissues during the final differentiation phases of the MS flowers, before meiosis takes place. Initially, these necrotic areas are small, later on they enlarge affecting the sporogenous tissue and tapetum. All the anthers in which necrosis has begun finally become aborted and lack pollen grains. The second event is manifested in the anthers of the INT flowers. Previous to the release of the microspores from the callosic envelope, vacuolisation of the tapetal cells takes place. The tapetum does not properly carry out its secretory function. It accumulates some substances in vacuoles and starch granules in plastids. The microspores degenerate in the vacuolate stage. In the epidermal and endothecial cells modifications are observed which may be related to the carbohydrate metabolism. Indehiscent, whitish anthers containing inviable microspores result. We have not found significant differences between the mitochondria in the anthers of the fertile flowers and MS or INT flowers. But we suggest, for both events, a metabolic failure, possibly controlled by cytoplasmic genes as the origin of male sterility. Paracrystalline material has been detected in microspore nuclei of developing INT anthers, though it does not seem to be related to the expression of male sterility.  相似文献   

11.
濒危植物南方红豆杉遗传多样性的RAPD分析   总被引:3,自引:2,他引:3  
采用RAPD技术检测了山西南部南方红豆杉8个种群的遗传多样性。利用21个10聚寡核苷酸引物共检测出134个位点,其中多态性位点123个,占91.79%,8个种群的遗传多态位点百分率分别为67.16%(红豆峡)、67.91%(凤凰谷)、66.42%(小梯河)、66.42%(蟒河)、50.75%(历山西峡)、43.28%(云蒙山)、78.36%(长治宾馆)、50.75%(磨河)。南方红豆杉的遗传多样性分析结果显示:Shannon指数为2.180,其中31.7%的遗传多样性来自种群间,68.3%来自种群内;Nei指数为0.571,种群间的遗传分化系数(Gst)为0.181。8个种群间的遗传相似性分析结果显示:壶关红豆峡和陵川凤凰谷种群间的遗传距离最小(0.109 2),壶关红豆峡和陵川蟒河种群间遗传距离最大(0.55)。本研究结果揭示,南方红豆杉自然种群具有较高的遗传多样性,其遗传多样性不是导致该种群濒危的主要原因,导致南方红豆杉种群濒危的原因可能与南方红豆杉自然种群及群落所在生境的直接破坏及其本身生物学和生态学特性所导致的自然更新不良有着密切的联系。  相似文献   

12.
Picrorhiza kurrooa Royle ex Benth., a high value medicinal herb of alpine Himalaya and a source of hepatoprotective picrosides, is listed as ‘endangered’ due to heavy collection from its natural habitat. The present report deals with successful propagation of this species using both conventional and in vitro techniques. Vegetative propagation was achieved by rooting runner cuttings with indole-3-butyric acid (IBA) or α-naphtheleneacetic acid (NAA) treatment before planting. Nearly 87% rooting success was achieved by treatment of cuttings with 50.0 μM IBA. Seeds were given a presoaking treatment with gibberellic acid (GA3), 6-benzylaminopurine (BAP) or a combination of both to influence germination. More than 11-fold improvement in germination was recorded in seeds treated with 250.0 μM GA3. In vitro shoot multiplication was achieved through sprouting of axillary buds using nodal segment. Multiple shoots were formed following culture for 3 weeks on Murashige and Skoog (MS; 1962. Physiologia Plantarum 15: 473–497) medium containing 1.0 μM BAP. Cent percent rooting success, without basal callus formation, was observed when individual microshoots were placed in MS medium supplemented with IBA. The plantlets raised using conventional as well as tissue culture methods were hardened and successfully established in the experimental field located at 2450 m elevation. In addition, strategies have been discussed to encourage cultivation and in situ conservation of this highly valued medicinal herb so as to reduce pressure on its natural populations.  相似文献   

13.
Cunila menthoides is classified as a xylopodiferous subshrub found in fragmented environments threatened by local agriculture and pasture activities. The species presents strong and pleasant smell, and is commonly used in south Brazilian folk medicine. Based on the species’ medicinal and aromatic potential, the aim of this work was to examine the genetic variation within and among C. menthoides populations, focusing on the conservation of this species. In this context, six C. menthoides populations collected in Rio Grande do Sul, Brazil, were analyzed by ISSR. The populations were sorted as four clusters according to geographic distribution. The six C. menthoides populations analyzed presented low genetic variability, indicating that each population derives from a limited number of plants in a low gene flow scenario. In situ and ex situ conservation approaches may be useful in this species. Conservation strategies for the species should be based on in situ and ex situ approaches.  相似文献   

14.
Lopesia indaiensis (Diptera, Cecidomyiidae), a new species of gall midge found causing galls on Andira fraxinifolia (Fabaceae), an endemic plant species in Brazil, is described based on larva, pupa, male and female. L. indaiensis galls were collected in Dores do Indaiá, State of Minas Gerais, Southeastern Brazil. Larvae were removed from the galls and pupae and adults were obtained by rearing. The specimens were mounted on slides and the most important morphological characters were illustrated. The new species was compared to the other species of Lopesia.  相似文献   

15.
Hyptis martiusii Benth. is an aromatic plant found in abundance in northeastern Brazil that is used in ethnomedicine to treat gastric disorders. The aim of this study was to elucidate the mechanisms of action involved in the gastroprotection of the essential oil of Hyptis martiusii (EOHM) and to evaluate its healing capacity. Wistar rats were exposed to different protocols and subsequently were treated with 1% Tween-80 aqueous solution (negative control), pantoprazole, carbenoxolone, N-acetylcysteine (depending on the specificity of each model) or EOHM. The antisecretory activity (basal or stimulated) was determined using the pyloric ligature method. The gastroprotective action of nitric oxide and sulphydryl groups (–SH groups), as well as the quantification of adherent mucus and the levels of malondialdehyde and –SH groups in gastric mucosa, were evaluated using ethanol-induced gastric ulcer model. The healing ability was evaluated using the acetic acid-induced gastric ulcer model and histological and immunohistochemical analysis (HE, PAS and PCNA). EOHM (400 mg/kg) reduced the volume and acidity of gastric secretion stimulated by histamine and pentagastrin. The gastroprotective effect of EOHM involves the participation of endogenous sulfhydryl groups. EOHM increased mucus production (54.8%), reduced levels of MDA (72.5%) and prevented the depletion of –SH groups (73.8%) in the gastric mucosa. The treatment with EOHM reduced in 70.3% the gastric lesion area, promoting significant regeneration of the gastric mucosa, as confirmed by histological analysis and analysis of proliferating cell nuclear antigen. The results show that gastroprotective effect of EOHM is mediated by cytoprotective and antioxidant mechanisms and by their antisecretory activity, and suggest that the essential oil of Hyptis martiusii is a promising candidate for the treatment of gastric ulcers.  相似文献   

16.
Macbridea alba is a herbaceous perennial mint endemic to the panhandle region of Florida. We used starch gel electrophoresis to describe allozyme diversity and genetic structure in this federally threatened plant. Ten populations were analyzed, with an average sample size of 47 plants (range 41-48 plants) per population. Of the 22 loci analyzed, 11 (50%) were polymorphic, with an average of 36.2% of the loci polymorphic within populations. Gene diversity measures for the species (Hes = 0.121) and for the populations (Hep = 0.099) were slightly higher than means found for other surveyed endemic plants. Compared to nine previously analyzed woody mints, however, M. alba is genetically depauperate. Little genetic structure was evident within the species, with 92% of the total genetic variation found within populations. Genetic identities between population pairs were high (mean I = 0.98). The perennial life habit of M. alba and long-distance pollination by bumblebees may contribute to the maintenance of genetic diversity within this threatened species.  相似文献   

17.
Ferula cupularis (Boiss.) Spalik et S. R. Downie is an endangered endemic Iranian medicinal plant with occurrence restricted to Fars and Kohkilooyeh Boyerahmad provinces, Iran. F. cupularis is cited for strong antibacterial activity, usages in foodstuffs preservation, and has long been used by local peoples for ulcer treatment. In this research, the aerial parts of F. cupularis wild populations were collected from three natural habitats: Eqlid-Kaftar (FC1), Kakan (FC2), and Sepidan-Komohr (FC3), to assess phytochemical diversity and antioxidant activity. The quantity of essential oil (EO) ranged remarkably from 0.42 to 0.72 % v/w among the populations. Results obtained from the EO analysis by GC-FID and GC/MS detected up to 56 compounds. α-Pinene (21.65–31.53 %), sabinene (4.74–11.39 %), phellandrene (1.78–5.1 %), δ-3-carene (1.85–7.18 %), limonene (4.12–7.45 %), (Z)-β-ocimene (9.08–17.64 %), and elemicin (0.23–5.74 %) were the major compounds of EOs varied significantly among the populations. Moreover, total phenol content (250.54 to 387.45 mg gallic acid/100 g dry weight (DW)) and flavonoids (34.38 to 41.12 mg quercetin/100 g DW) of methanolic extracts varied substantially among the populations. Antioxidant activities of F. cupularis EOs and extracts were assessed by DPPH (2,2,1-diphenyl-1-picrylhydrazyl) radical scavenging method. EOs exhibited EC50 values ranging from 8.88 to 9.67 μg mL−1 and the EC50 values for the extract ranged from 941.36 to 1335.96 μg mL−1 within the populations. Results demonstrated significantly different levels of antioxidant capacities among the studied populations. Monitoring the data, the population collected from Eqlid-Kaftar (FC1) was selected as the most potent population concerning the highest EO content and antioxidant activity level. The obtained data provided new insights for an initial source of breeding plans and ultimately massive production for food and pharmaceutical industries.  相似文献   

18.
Analysis by GC and GC/MS of the essential oil obtained from above-ground parts of Micromeria dalmatica Benth. allowed the identification of 116 components, comprising 93.6% of the total oil composition. The major compounds are 3-oxygenated p-menthane monoterpenes and were identified as pulegone (29.6%), menthone (11.7%), and piperitenone (10.8%). The chemical composition of this and additional 30 oils obtained from selected Micromeria Benth. taxa were compared by using multivariate statistical analysis (agglomerative hierarchical cluster analysis and principal component analysis (PCA)). The results of statistical analyses, as well as the domination of different concurrent p-menthane-skeleton-type monoterpene biosynthetical sub-branches in the compared M. dalmatica samples, implied the occurrence of at least two different chemotypes of the mentioned species.  相似文献   

19.
明确珍稀濒危小种群阜康阿魏(Ferula fukanensis)的遗传多样性和遗传结构,是对其制定有效的保护和管理策略的基础和前提。本研究基于10对多态性好且可以稳定扩增的SSR引物对来源于3个居群87个珍稀濒危植物阜康阿魏的遗传多样性和遗传结构进行分析。结果显示:小种群的阜康阿魏具有相对较高的遗传多样性,居群间Nei’s基因多样性指数(hS)为0.514,总的Nei’s基因多样性指数(hT)为0.516,观测杂合度(Ho)为0.881,期望杂合度(He)为0.512,香农信息指数(I)为0.836,多态位点百分率(PPB)为100%,遗传分化程度较低(Fst=0.007),95.9%的变异发生在居群内,遗传距离与地理距离无显著相关性,66.7%的居群遭遇了遗传瓶颈。结果表明,阜康阿魏遗传变异丰富,有较高的进化潜力。结合该种野外种群现状,建议建立保护区,开展就地保护,并加强引种和人工繁育等迁地保护措施,辅助阜康阿魏保育。本研究可为阜康阿魏植物资源保护提供理...  相似文献   

20.
利用微卫星(SSR)标记对来自山西和陕西两省的7个翅果油树(Elaeagnus mollisDiels)种群进行遗传多样性和遗传结构研究。10对SSR标记共检测到126个位点,其中多态位点114个。在物种水平上,平均多态位点百分率为90.79%,有效等位基因数(Ne)、Nei基因多样性指数(H)和Shannon多样性指数(I)分别为1.6072、0.3166、0.4603;在种群水平上,多态位点百分率为61.99%,有效等位基因数(Ne)、Nei’s基因多样性指数(H)、Shannon多样性指数(I)分别为1.5445、0.2683、0.3815。遗传分化系数GST为0.2074,表明了翅果油树种群的遗传变异主要存在于种群内。基因流Nm为1.9111〉1,说明种群间基因交流可以阻止由于遗传漂变导致的遗传分化。聚类结果表明,翅果油树种群间的遗传距离与地理距离有一定的相关性,经Mantel检验,种群的地理距离与遗传距离之间呈正相关,但未达到显著水平(p〉0.05)。结果表明,遗传多样性水平与物种本身特性和不同干扰生境有关,濒危植物并不一定表现为遗传变异水平的降低。  相似文献   

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