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1.
用Pot2-rep-PCR方法获得的稻瘟病菌（Magnaporthe grisea）指纹图谱基本反映了中等重复倒位单元Pot2的拷贝数和在基因组中的分布,理论扩增最短片段长度应为1 199 bp.而在江苏和中国北方来源粳稻菌株中常发现有600 bp左右长度的条带.经回收测序该片段P1长度为606 bp,其中Pot2-1端384 bp命名为S1,与Pot2的对应序列完全同源,Pot2-2端222 bp命名为S2,与Pot2对应序列同源性达89.3%.以P1及Pot2引物对可扩增的理论片段范围内的另一新扩增片段P2作为探针分别与10个DNA指纹差异明显并均含606 bp片段的菌株PCR产物进行Southern杂交,结果为P1与Pot2 rep-PCR产物的每条带均有同源性,而P2与扩增产物的最小条带没有同源性,认为P1片段的产生原因为Pot2片段的部分缺失或者部分片段在基因组中移动后整合到另一个Pot2之前. 相似文献
2.
本研究采用改良CTAB法分别提取18份甘肃本地产当归、黄芪和大黄基因组DNA,并用PCR分别扩增其ITS1-5.8S-ITS2序列、直接测序并作序列同源性比对分析。双向测序分析结果表明,甘肃6个不同产地当归rDNA的ITS1、5.8S和ITS2序列一致,片段长度分别为215bp、162bp和223bp;供试的黄芪ITS1、5.8S和ITS2序列分别为228bp、164bp和210bp;大黄ITS1、5.8S和ITS2序列分别为160bp、159bp和164bp。供试材料的ITS1-5.8S-ITS2核苷酸序列已提交GenBank。本研究为提供甘肃当归、黄芪和大黄指纹图谱鉴别的分子标记、其道地性药材的分子鉴定和品质评价提供参考。 相似文献
3.
柑桔黄龙病病原16S rDNA克隆、测序及实时荧光PCR检测方法的建立 总被引：22，自引：0，他引：22
克隆并测定了中国柑桔黄龙病病原16SrDNA基因序列，经同源性比较，表明属于柑桔黄龙病菌(Liberobacter asiaticum)亚洲种中一个新株系(中国厦门株系)。依据获得的16SrDNA特异序列，建立了柑桔黄龙病病菌检测的实时荧光PCR方法，并应用此方法对柑桔样品进行了检测。结果显示，该检测方法具有快速、特异、敏感、重复性好等优点。该方法为柑桔黄龙病的检测，特别是早期诊断、检疫和病害的综合治理奠定了基础。 相似文献
4.
从广西合浦县柑橘叶片表面分离到拮抗细菌菌株Bv10。该拮抗细菌对柑橘溃疡病菌的生长表现出很强的拮抗活性。根据16S rDNA序列同源性比较、形态学特征以及生理生化反应,将该菌株鉴定为枯草芽孢杆菌B acillus subtilis变种。在温室接种测试中,42.9%的柑橘溃疡病斑形成受到Bv10菌株的抑制。Bv10菌株在人工培养基上连续移植8次,对柑橘溃疡病菌生长的抑制力没有显著变化,该菌株表现对植物病原真菌具有较宽的抑菌谱。 相似文献
5.
用幼鸡成纤维细胞繁殖鸡传染性法氏囊病病毒(IBDV)Ts毒株,病毒颗粒经提纯后提取基因组dsRNA.根据已报道的加拿大OH株序列设计引物,用RT-PCR进行 cDNA扩增,获得976 bp、774 bp和997 bp的三个部分重叠的片段,分别克隆于pGEM-Teasy载体,利用SP6,T7特异引物及PCR引物进行序列分析,并连接为一个完整的大片段.结果表明,所克隆片段为2 665 bp的IBDV VP1基因的大开放读框.序列分析表明:Ts株与OH株的核苷酸序列同源性为91 %;与DRT毒株的氨基酸序列同源性为42.5 %.尽管Ts株与DRT株的整体同源性很低,但在VP1蛋白的中部仍发现有高同源区段.在两种病毒中均发现与GTP结合蛋白、依赖于RNA的RNA聚合酶(RdRp)相关的保守序列.然而,与单链RNA病毒不同的是:作为RdRp家族特征的G-D-D序列在两种病毒中都未发现. 相似文献
6.
提高土壤微生物的可培养性,获得纯培养微生物菌株,是微生物生态学研究的基础。采用三种培养基对土壤细菌进行分时段计数,以细菌通用引物扩增细菌16S rDNA片段,用限制性内切酶HhaI酶切PCR产物,对酶切图谱进行分型,研究不同培养方法对土壤细菌多样性和可培养的影响。结果表明,LB、CSEA、W SA培养基192 h后每g干土获得的细菌数量分别为14.84×107、10.27×107和6.91×107CFU,但微生物多样性指数以W SA为最高,LB多样性指数最低;三种培养基培养的细菌菌群有一定的相似性,LB和CSEA培养基间的Jaccard指数为57.69%,LB和W SA培养基之间为53.13%,而CSEA和W SA培养基的相似性指数达66.67%;16S rDNA测序结果表明,所获得的土壤细菌优势种群在分类方面主要属于γ-和β-变形杆菌以及放线菌亚门,其中某些OTUs中的16S rDNA序列与Burkholderiaceae bacterium、Rhodococcus和Mycobac-terium属具有较高的同源性,推测其细胞能够分泌复苏促进因子,有效地提高土壤细菌的可培养性。 相似文献
7.
根据牛、羊Y－染色体性别决定区域（SRY）的同源性设计了一对PCR引物，对8个绵羊胎儿成纤维细胞系SFF1－8进行了性别鉴定。阳性对照和细胞系SFF1、2、6、7扩增得到130bp片段，阴性对照、空白对照及细胞系SFF3、4、5、8没有扩增带。通过序列测定和同源性分析，证明PCR产物为SRY基因片段，说明有130bp扩增带的细胞系为雄性；无扩增带的为雄性。结果表明，该法具有简单、快速、准确的特点，可应用于转基因克隆动物研究中对体细胞系的早期性别鉴定。 相似文献
8.
以伪狂犬病病毒GB株细胞培养物为模板，用PCR方法扩增蛋白激酶(PK)基因，对其进行了克隆、序列测定，并与PRV NIA-3株、Ka株和其他α-疱疹病毒进行了同源性比较。结果显示：所扩增的PK基因片段长1396bp，该片段包含一个开放阅读框(ORF)，长1005bp，编码由334个氨基酸组成的蛋白质。与NIA-3株及Ka株的核苷酸同源性为98．4％和97．5％，基因编码区氨基酸序列的同源性为98．2%和96．4％。具有真核细胞丝氨酸／苏氨酸蛋白激酶氨基酸亚结构域特征序列，而且α-疱疹病毒PK基因具有一些特征性的、共有的氨基酸序列。为今后研究PK基因的功能和构建PK缺失株奠定了基础。 相似文献
9.
高羊茅CBF转录激活因子基因片段的克隆 总被引：4，自引：0，他引：4
根据拟南芥CBF基因序列的保守区设计 1对特异引物 ,采用PCR方法从高羊茅基因组中扩增出 1个DNA片段并克隆到pUCm T载体中。经序列测定和分析 ,该片段长 60 8bp ,与 3个拟南芥CBF基因的核苷酸及其推导氨基酸序列分别具有 81～ 84%和 75～ 79%的同源性 ,而且推导氨基酸序列中包含有同源性更高的AP2DNA结合域以及CBF蛋白的两段特征序列PKK RPAGRxKFxETRHP和DSAWR。这些结果表明 ,本研究克隆的片段为高羊茅CBF基因片段 相似文献
10.
由丁香假单胞菌(Pseudomonas syringae pv.averrhoi)引起的杨桃(Averrhoa carambola)细菌性斑点病是杨桃生产上的重要病害.本研究利用细菌16S～23S rDNA间的内源转录间隔区(internal transcribed spacer ITS)序列通用引物Ll(5'-AGTCGTAACAACGTAGCCGT-3')和L2(5’-GTGCCAAGGCATCCACC-3’)扩增参试菌株的基因组DNA;并对其PCR产物进行克隆测序,经多重比对分析后设计出杨桃细菌性斑点病菌的特异性引物PsaveF(5'-CTTATCGACGACTCAGCTGCG-3’)和PsaveR(5’-TCATGCGTTGATCGTCAGGATC-3').此引物可以从杨桃细菌性斑点病菌基因组DNA中扩增出373bp的特异性片段,而其余参试的细菌无扩增条带,该引物检测的灵敏度可达10 pg,且可从自然发病的杨桃组织中扩增出特异性条带.表明该方法可以应用于杨桃细菌性斑点病的快速、灵敏、可靠的检测.此外,本研究对多种病原细菌的ITS序列进行比对分析,发现该病菌与核果树细菌性溃疡病菌Pseudomonas syringae pv.morsprunorum是近源种.该检测技术对杨桃细菌性斑点病害的控制有一定的实用意义. 相似文献
11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响 总被引：2，自引：2，他引：0
【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。 相似文献
12.
Aleš Lebeda Ivana Doležalová Eva Křístková Barbora Mieslerová 《Genetic Resources and Crop Evolution》2001,48(2):153-164
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions. 相似文献
13.
Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. 相似文献
14.
Thomas Larsen Jesper Luxhøi Jakob Magid Lars Stoumann Jensen Paul Henning Krogh 《Biology and Fertility of Soils》2007,44(1):59-68
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization
and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition
with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the
decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots
with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass,
soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration,
N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially
(<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation
in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils,
indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but
the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation
for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community
performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea. 相似文献
15.
《中国生态农业学报》2014,(6)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
16.
《中国生态农业学报》2014,(7)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
17.
《中国生态农业学报》2014,(8)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
18.
I.L. Boyd 《Biological conservation》2010,143(7):1664-1674
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options. 相似文献
19.
Soil-profile distribution of primary and secondary plant-available nutrients under conventional and no tillage 总被引：1，自引：0，他引：1
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate. 相似文献
20.
M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils. 相似文献