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1.
为了探讨银白杨、马氏杨及银白杨×马氏杨杂交子代间的遗传多样性参数及个体聚类关系,利用8对引物对银白杨、马氏杨及银白杨×马氏杨杂交子代4个样本进行了AFLP分析。结果表明,8对引物共扩增出780条扩增谱带,其中多态性条带数为715条,多态性比例为91.65%,平均有效等位基因数为1.5017,Nei’s平均遗传多样性指数为0.3065,Shannon平均信息指数为0.4679。不同杂交子代在E-AAC/M-CAG引物对上均有特异性位点,这些特异位点可用于品种鉴定。聚类研究发现,在相似系数为0.76时,试验样品分成2个AFLP群,其中马氏杨为1个AFLP群,银白杨及2个杂交子代为1个AFLP群;当相似系数为0.78时,银白杨和2个杂交子代的AFLP群又划分为2个亚群,其中杂交子代1和杂交子代2聚合为亚群1,银白杨为亚群2。本研究的结果多态性比例很高,对样品的区分率达到100%,为杨树AFLP分析检测提供了指导借鉴价值。 相似文献
2.
云南红豆杉天然种群遗传多样性研究 总被引：9，自引：1，他引：9
采用垂直板式聚丙烯酰胺凝胶电泳，检测了云南红豆杉（Taxus yunnanensis)雌配子体的5种等位酶，并以10个基因位点编码的5个酶系统，分析了滇西北3个云南红豆杉天然种植的遗传多样性与遗传分化。结果表明，群体的多态位点比例是0．77；群体的平均杂合性观察值是0．302；预期值为0．3320；每个基因位点发现的等位基因数是2．05，有效等位基因平均数是1．466。对10个基因位点的基因多样性测定表明，种群间的分化占14．66％。总的基因多样性约85％产生于种群内。群体间的平均遗传距离是0．118。 相似文献
3.
《中南林业科技大学学报(自然科学版)》2016,(5)
采用ISSR分子标记技术,对我国濒危植物福建柏的7个种群进行遗传多样性分析。结果显示:17个引物共扩增出202个位点,多态性位点167个,占总位点的82.67%;引物UBC849可以将24份福建柏样本完全鉴别出来;7个福建柏种群的多态位点百分率在17.82%~54.95%之间;群体总观测等位基因数Na为1.821 8,有效等位基因数Ne为1.431 3,Nei指数为0.258 2,Shannon指数为0.394 0;种群内平均Na指数为1.372 0,平均Ne指数为1.289 2,平均Nei指数为0.160 0,平均Shannon指数为0.203 5;基因分化系数Gst为32.41%,种群间基因流Nm为0.878 0;7个种群遗传相似度在0.668 3~0.806 9之间,遗传距离在0.214 5~0.404 3之间;利用UPGMA法进行聚类,将泉州市、福州市和龙岩市种群分为第一类,将南平市、三明市和漳州市种群分为第二类,将宁德市种群分为第三类。 相似文献
4.
【目的】分析长柄双花木种群遗传多样性和遗传结构,探讨其种群演化历史,加深对该物种进化过程的理解,为其遗传资源保护、开发利用提供理论基础。【方法】利用15对能获得高多态性扩增产物的SSR引物,采用TP-M13-SSR技术检测长柄双花木全分布区12个自然种群261株个体的遗传多态性,应用Gene Marker软件进行基因分型,FSTAT估算遗传参数,ARLEQUIN进行分子方差分析,STRUCTURE对所有个体进行Bayesian聚类分析,Bottleneck检测种群遗传瓶颈效应。【结果】15个SSR位点共检测到129个等位基因,平均每个位点上的等位基因数和有效等位基因数分别为8.6和3.5,观测杂合度和期望杂合度分别为0.37和0.67;种群水平上,平均每个位点上的等位基因数和有效等位基因数分别为3.4和2.1,观测杂合度和期望杂合度分别为0.35和0.43;私有基因丰富度和种群内近交系数分别为0.15和0.19。除道县种群外,其他种群极显著偏离Hardy-Weinberg平衡,表现出杂合子缺失。种群间遗传差异极显著(P0.001)。12个种群可归类为2个类群,大多数个体谱系清晰。在近期的进化过程中,种群遗传结构稳定,未经历遗传瓶颈事件。【结论】长柄双花木在物种和种群水平上,维持较丰富的遗传变异,具有较高的进化潜力。近期生境碎片化和遗传漂移对长柄双花木种群遗传多样性影响较小。种群间的自然屏障、气候变迁和人类干扰导致的种群生境碎片化,是其现代地理分布格局和种群遗传结构的主要成因,这可为该物种遗传资源保护策略的制定提供科学依据。 相似文献
5.
白皮松天然群体遗传多样性的等位酶分析 总被引：1，自引：0，他引：1
采用8种等位酶对白皮松4个天然群体的遗传多样性和遗传分化进行了研究.在4个群体中共检测到10个基因位点,15个等位基因,其中6个位点为多态位点;群体总体水平多态位点比率P=60%,平均有效基因数A=1.92,平均期望杂合度He=0.106,种群平均遗传距离为0.006 8.南漳白皮松群落平均等位基因数A=1.9,平均有... 相似文献
6.
本研究在对选择性扩增引物进行筛选的基础上,对银白杨、N001杨及银白杨×N001杨杂交子代共10个样本进行了AFLP试验,并利用Popgene和NTsys软件分别对遗传多样性参数及个体聚类进行分析。结果表明:筛选出的8对选择性扩增引物,共扩增出969条谱带,多态性条带数929条,多态性比例为95.76%,平均有效等位基因数为1.4329,Nei's平均遗传多样性指数为0.2662,Shannon平均信息指数为0.4161。不同杂交子代在E-ACC/M-CAC引物对上均有特异位点,这些特异位点用于申报优良品种保护。在通过NTsys软件聚类后,在遗传相似系数为0.76时,将10个试样分为2个大支,其中N001杨为1个AFLP群,银白杨及8个杂交子代为1个AFLP群;当遗传相似系数为0.79时,银白杨与8个杂交子代的AFLP群又细化为2个亚群,其中杂交子代2和杂交子代6聚合为亚群1,银白杨和其余6个杂交子代为亚群2。本研究的结果多态性比例很高,对样品的区分率达到100%,为杨树AFLP分析检测提供了较好的应用和指导借鉴价值。 相似文献
7.
腰果混杂群体的遗传组成分析 总被引：2，自引：0，他引：2
利用AFLP分子标记技术对54个单株构成的腰果混杂群体的遗传组成进行分析,评估其遗传变异水平,旨在为合理有效利用该资源提供科学理论依据。结果显示,筛选出的8对引物组合共扩增出467条谱带,其中,多态性带为179条。多态性带百分率、观测等位基因数、有效等位基因数、Nei’s基因多样性指数和Shannon信息指数分别为38.33%、1.383 3、1.150 4、0.094 6和0.149 2。遗传距离的变异范围在0.017 1~0.250 5之间,平均为0.103 5。UPGMA聚类结果将54个样株归于4个复合组和2个独立组。 相似文献
8.
引进葡萄柚品种基因资源的AFLP分析 总被引：3，自引：0，他引：3
采用AFLP分子标记技术,对引进的9个葡萄柚品种基因资源进行分析,评价引进资源的遗传多样性,揭示遗传结构和品种间亲缘关系,为引进葡萄柚品种的进一步开发利用和遗传改良提供基础信息。结果表明,筛选出的7对引物共扩增出263条带,多态带比率为7.22%。多态性标记百分率、观测等位基因数、有效等位基因数、Nei’s基因多样性指数和Shannon信息指数在物种水平分别为7.22%、0.023 4、0.008 0、0.6592和0.258 5,而在品种水平它们分别为2.41%、1.024 1、1.013 2、0.008 0和0.012 2。基因分化系数Gst为0.659,表明葡萄柚的遗传差异主要来自于品种之间。9个品种间的遗传距离变幅在0.000 5~0.037 1之间,平均为0.025 8。基于UPGMA的聚类结果将9个品种分为2组,火焰、矮化、亨路比、哈路比、帕利斯和瑞路比聚为一组,里德马叙、里约红和星路比构成另一组。 相似文献
9.
利用AFLP分子标记技术,采用8对引物对6个香榧天然群体的92个个体进行了总基因组DNA水平上的多态性检测,共检测出364个位点,其中多态性位点63个.方差分析表明:基因谱带频率在群体间差异不明显,方差分量贡献率在群体间占11.14%,群体内占88.86%.6个群体均具有丰富的遗传多样性,多态位点百分率为79.73%～98.41%,其中绍兴>东白湖>磐安>钟家岭>嵊州>黄山,且群体内遗传多样性大于群体间遗传多样性.等位基因数为1.7939～1.9841,有效等位基因数为1.5416～1.6759,Shannon信息指数为0.4548～0.5471.群体分化系数为0.1136,群体内遗传多样性为0.3512,基因流为3.8997.遗传一致度平均值为0.9174,遗传距离平均值为0.0797.根据遗传一致度进行了UPGMA聚类分析. 相似文献
10.
珍稀濒危观赏竹种筇竹遗传多样性研究 总被引：1，自引：0，他引：1
《竹子研究汇刊》2016,(1)
对筇竹Qiongzhuea tumidinoda居群间及居群内遗传多样性进行了研究。通过基因组多态性分析,筛选出13个随机引物对筇竹样品进行扩增,得到清晰可重复且多态性明显的条带,多态位点率为76.38%。在NTSYS程序中,统计这些扩增产物用来计算遗传相似性系数和遗传距离,建立UMPGA(不加权算术平均法)聚类图,得出筇竹居群间的基因多样性大于居群内的结论,在此基础上,探讨筇竹保护对策和建议。 相似文献
11.
12.
从落叶松梢栖真菌筛选出对落叶松枯梢病病原菌有抑制作用的菌株,对落叶松枯梢病进行生物防治。将自落叶松梢部分离到的11种梢栖真菌与落叶松枯梢病病原菌进行对峙培养,根据被覆盖程度、抑菌率、拮抗系数和防治预试验的结果,综合评价后发现:粪生粪壳、深绿木霉和球毛壳3种梢栖真菌对落叶松枯梢病有良好的拮抗作用。利用这3个菌株在黑龙江省勃利县通天一林场国富沟进行林间防治试验,结果表明:防治效果为粪生粪壳>代森锰锌400倍液>深绿木霉>球毛壳;深绿木霉和粪生粪壳喷洒浓度50%和球毛壳喷洒浓度75%时,真菌多样性最多,梢栖真菌系统较其他浓度更为稳定,与化学防治相比,既达到了防治目的又具有不污染环境的优势。 相似文献
13.
The Eastern Black Sea Region has an extensive flora because of ample rainfall lasting all year. In this study, antimicrobial effects of 74 crude extracts of 22 endemic plants were investigated. Among the 30 active crude extracts, water-insoluble crude extracts from Betula medwediewii, Heracleum platytaenium, Primula longipes, Anthemis cretica ssp. argaea and Centaurea helenioides were the prominent ones with their MIC values. 相似文献
14.
Euphorbia acanthothamnos, E. macroclada and E. rigida were investigated for their antioxidant activity. The antioxidant potential of extracts of E. acanthothamnos, E. macroclada and E. rigida was evaluated using different complementary antioxidant tests. 相似文献
15.
Oliveira DF Pereira AC Figueiredo HC Carvalho DA Silva G Nunes AS Alves DS Carvalho HW 《Fitoterapia》2007,78(2):142-145
A screening was conducted with 26 plants collected in the Brazilian southeast region, to identify plant extracts with antibacterial properties against Aeromonas hydrophila, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus. Initially, the agar diffusion method was employed. Then, those extracts presenting activity were submitted to a broth microdilution assay to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). It was observed that 13 of the tested extracts showed antibacterial activity. The best results were obtained with those from Lantana lilacina and Phyllanthus tenellus. 相似文献
16.
Growth and physiological response of six Australian rainforest tree species to a light gradient 总被引：1，自引：0，他引：1
An understanding of growth and photosynthetic potential of subtropical rainforest species to variations in light environment can be useful for determining the sequence of species introductions in rainforest restoration projects and mixed species plantations. We examined the growth and physiology of six Australian subtropical rainforest tree species in a greenhouse consisting of three artificial light environments (10%, 30%, and 60% full sunlight). Morphological responses followed the typical sun-shade dichotomy, with early and late secondary species (Elaeocarpus grandis, Flindersia brayleyana, Flindersia schottiana, and Gmelina leichhardtii) displaying higher relative growth rate (RGR) compared to mature stage species (Cryptocarya erythroxylon and Heritiera trifoliolatum). Growth and photosynthetic performance of most species reached a maximum in 30–60% full sunlight. Physiological responses provided limited evidence of a distinct dichotomy between early and late successional species. E. grandis and F. brayleyana, provided a clear representation of early successional species, with marked increase in Amax in high light and an ability to down regulate photosynthetic machinery in low light conditions. The remaining species (F. schottiana, G. leichhardtii, and H. trifoliolatum) were better represented as falling along a shade-tolerant continuum, with limited ability to adjust physiologically to an increase or decrease in light, maintaining similar Amax across all light environments. Results show that most species belong to a shade-tolerant constituency, with an ability to grow and persist across a wide range of light environments. The species offer a wide range of potential planting scenarios and silvicultural options, with ample potential to achieve rapid canopy closure and rainforest restoration goals. 相似文献
17.
Insecticidal activity of Vitex mollis 总被引：3，自引：0，他引：3
Organic extracts from the leaves of Vitex mollis were assessed for their toxic effect on fall armyworm neonate larvae (Spodoptera frugiperda), an important insect pest of corn. The extracts showed insecticidal and insect growth regulatory activity, being CHCl(3)-MeOH (1:1) extract the most active, also found to be toxic in the Artemia salina test. 相似文献
18.
Ungulate herbivory of regenerating conifers in relation to foliar nutrition and terpenoid production 总被引：1，自引：0，他引：1
Owen T. BurneyDouglass F. Jacobs 《Forest Ecology and Management》2011,262(9):1834-1845
Ungulate browsing greatly influences regeneration dynamics of some forest ecosystems, yet the relationship between browse susceptibility and foliar chemistry of forest tree seedlings is not well understood. We applied field fertilization (15N-9P-10K controlled-release fertilizer at 0, 20, 40, and 60 g per seedling) and investigated how subsequent changes in terpenoid production and foliar nutrition influence ungulate browse preference for Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), western hemlock (Tsuga heterophylla Raf. Sarg.), and western redcedar (Thujaplicata Donn ex D. Don) seedlings across four sites in northwestern Oregon, USA. Fertilization increased foliar N concentration of all three species, but above-ground growth of only Douglas-fir and western hemlock. Foliar monoterpene concentrations for western hemlock and western redcedar also increased at higher fertilization rates, while Douglas-fir monoterpene production was not affected by fertilization. Regardless of monoterpene levels, ungulate browse preference was greater for fertilized western hemlock seedlings. The opposite response, however, was observed for western redcedar at two of the four study sites where the likelihood of browse was greater for non-fertilized than fertilized seedlings. Differences in browse preference among species may depend on the type and amount of individual monoterpenes manufactured in response to fertilization. Western redcedar produce α- and β-thujone, oxygenated monoterpenes known to promote gastroenteritis and possibly inhibit microbial rumen activity, which were absent from Douglas-fir or western hemlock. Higher concentrations of α- and β-thujone associated with increasing fertilizer rate provide a plausible explanation as to why ungulates preferred non-fertilized western redcedar. Our results illustrate species-specific adaptation in browse avoidance and selective ungulate browsing behavior of individual trees as linked to foliar chemistry. 相似文献
19.
Christopher J. Fettig Stephen R. McKelvey Daniel R. Cluck Sheri L. Smith William J. Otrosina 《Forest Ecology and Management》2010
Many forests that historically experienced frequent low-intensity wildfires have undergone extensive alterations during the past century. Prescribed fire is now commonly used to restore these fire-adapted forest ecosystems. In this study, we examined the influence of prescribed burn season on levels of tree mortality attributed to prescribed fire effects (direct mortality) and bark beetles (Coleoptera: Curculionidae, Scolytinae) (indirect mortality) in ponderosa pine, Pinusponderosa Dougl. ex Laws., and Jeffrey pine, Pinusjeffreyi Grev. and Balf., forests in California, USA. A total of 816 trees (9.9% of all trees) died during this 3-yr study. Significantly higher levels of tree mortality (all sources) occurred following early and late season burns compared to the untreated control, but no significant difference was observed between burn treatments. The majority (461 trees) of tree deaths were attributed to direct mortality from prescribed burns and was strongly concentrated (391 trees) in the smallest diameter class (<20.2 cm diameter at breast height, dbh). For the largest trees (>50.7 cm dbh), significantly higher levels of tree mortality occurred on early season burns than the untreated control, most of which resulted from indirect mortality attributed to bark beetle attacks, specifically western pine beetle, Dendroctonus brevicomis LeConte, and mountain pine beetle, D. ponderosae Hopkins. Red turpentine beetle, D. valens LeConte, was the most common bark beetle species found colonizing trees, but tree mortality was not attributed to this species. A total of 355 trees (4.3% of all trees) were killed by bark beetles. Dendroctonus brevicomis (67 trees, 18.9%) and D. ponderosae (56 trees, 15.8%), were found colonizing P. ponderosa; and Jeffrey pine beetle, D. jeffreyi Hopkins, was found colonizing P. jeffreyi (seven trees, 2.0%). We also found pine engraver, Ips pini (Say) (137 trees, 38.6%), and, to a much lesser extent, Orthotomicus (=Ips) latidens (LeConte) (85 trees, 23.9%) and emarginate ips, I. emarginatus (LeConte) (3 trees, 0.8%) colonizing P. ponderosa and P. jeffreyi. Few meaningful differences in levels of indirect tree mortality attributed to bark beetle attack were observed between early and late season burns. The incidence of root and root collar pathogens (Leptographium and Sporothrix spp.), including species known to be vectored by bark beetles, was low (18% of trees sampled). The implications of these and other results to management of P. ponderosa and P. jeffreyi forests are discussed in detail. 相似文献
20.
The extracts from leaves, heartwood, barks and roots of the Streblus asper were investigated for anti-HBV activities, separately. The results suggested that the MeOH extracts of the heartwood, barks, and roots exhibited good anti-HBV activities. Further investigations displayed that ethyl acetate and n-butanol soluble parts of their MeOH extracts showed more significant anti-HBV activities. Moreover, a new lignan, together with 11 known compounds, was isolated from n-butanol-soluble part of MeOH extract of the roots of S. asper. The structures were elucidated by spectroscopic methods, including 1D NMR ((1)H NMR, (13)C NMR), 2D NMR (HMQC, HMBC) and HR-EI-MS experiments. Compounds 1-3 were evaluated for their anti-HBV activities. Honokiol showed significant anti-HBV activity with IC(50) values of 3.14μM and 4.74μM for HBsAg and HBeAg with no cytotoxicity respectively, while lamivudine (3TC, positive control) exhibited weak anti-HBV activity with IC(50) values of 11.81μM and 25.80μM for HBsAg and HBeAg respectively. 相似文献