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1.
The planting site, size, and health condition of street tree Ginkgo biloba in Beijing urban area were investigated and the influence factors were analyzed based on filed survey. The results showed that G. biloba were mainly planted in tree pit within strip planting median. The average height, diameter at breast height and canopy diameter were 8.11 m, 13.22 cm and 4.07 m, respectively, 82.9% trees were less than 10 m in height, and most G. biloba trees were still in the initial stage of height and diameter increment. The tree health status was described with three classes: class I (healthy), class II (fair) and class III (unhealthy). The percentage of class I, II and III for G. biloba trees in Beijing urban area accounted for 16.0%, 37.2% and 42.9% respectively. The results of analysis showed that the health status of G. biloba was associated with the site condition, tree size and management practices. The trees planted in urban forest patch grew better than the trees planted in green belts and tree pits; meanwhile, the bigger trees were healthier than the smaller ones. In addition, the effects of urban heterogeneous environment and human activities on the health of Ginkgo biloba were analyzed and the suggestions on management were launched. 相似文献
2.
Hiroki Inoue Shigehiro Kamoda Tamami Terada Yoshimasa Saburi 《Journal of Wood Science》1998,44(5):375-378
The contents of diterpenoids, ginkgolides A, B, and C, in seeds, embryos, and plantlets ofGinkgo biloba were analyzed to clarify the relations between organogenesis and terpene contents inG. biloba. There is so far no published report on the contents and changes in such terpenes in seeds and very young plantlets ofG. biloba. Ginkgolides were present in seeds and embryos. Plantlets cultured in both the dark and under illumination contained substantial amounts of ginkgolides, more abundant than in seeds and embryos. It is concluded that ginkgo yields ginkgolides in its early stage of development regardless of light. 相似文献
3.
[目的]研究银杏枝条部位、年龄对不定根形成的影响,并探讨其相应的叶、茎段中非结构碳水化合物(NSC)含量变化与扦插生根的关系。[方法]以50年生银杏树冠上、下部枝条的1、2和3年生位置的茎段为材料截取插穗,500 mg·L-1IBA与纯水对照处理基部60 s,在全光喷雾状态下研究扦插生根情况,并利用HLPC法分析相应部位叶和茎段中NSC含量。[结果]表明:银杏扦插不定根形成过程分为4个阶段,即0～4周愈伤形成期、4～6周愈伤膨大期、6～8周不定根开始形成期、8周后不定根伸长;生根部位主要在切口处。树冠上、下部位插穗的生根率未见明显差异,但随着枝龄的增加而明显降低。NSC分析表明:下部叶片NSC组分中多糖和总糖含量明显高于上部的,但茎段NSC的所有组分在上下部均无明显差异;随着枝龄的增加,相应位置叶片NSC各组分含量没有明显差异,但相应茎段NSC组分中葡萄糖、果糖、多糖、总糖、淀粉含量却明显降低,与生根率的变化趋势一致。此外,500 mg·L-1IBA处理并未明显提高生根率,还需进一步优化处理浓度。[结论]银杏树冠上部和下部枝条对不定根形成无影响;未处理枝条的枝龄与生根率呈负相关,而茎段NSC含量与生根率呈正相关;叶片NSC含量对不定根形成影响较小;生根方式以愈伤生根类型为主。该结论将为今后银杏扦插生根及其机制研究提供参考。 相似文献
4.
5.
Optimizing SSR-PCR system of Panax ginseng by orthogonal design 总被引：1，自引：0，他引：1
An orthogonal design was used to optimize SSR-PCR amplification system using Panax ginseng genomic DNA as template. Four levels of five factors （DNA template, Taq DNA polymerase, Mg^2＋, primer, and dNTP） and annealing temperature have been tested separately in this system. The results demonstrated the reaction efficiency was affected by these factors. Based on the results, a stable, productive and reproducible PCR system and cycling program for amplifying a ginseng SSR locus were obtained： 20 μL system containing 1.0 U Taq DNA polymerase, 2.0 mmol·L^-1 Mg^2＋, 0.2 mmol·L^-1 dNTPs, 0.3 μmol·L^-1 SSR primer, 60 ng· μla^-1 DNA template, performed with a program of 94℃ for 5 min, 94℃ for 30 s, annealing at 56.3℃ for 30 s, 72℃ for 1 min, 37 cycles, finishing at 72℃ for 7 min, and storing at 4℃. 相似文献
6.
Species-specific oligonucleotide primers for detecting wood rot fungi, Gloeophyllum trabeum, Trametes versicolor, Coniophora puteana, and Serpula lacrymans, and the primer detecting a group of related fungi to G. sepiarium were developed. These primer sequences were picked up from the internal transcribed spacer region between small-subunit rDNA
and large-subunit rDNA. The species selectivities of the developed primers were checked. Real-time polymerase chain reaction
(PCR) was carried out using these highly specific primers to quantitatively detect at least of 0.01 ng genome DNA of the target
species. This quantitative PCR was also used to differentiate the target species DNA from mixed species DNA. A PCR-based technique
using the species-specific primers would be applicable to multiple-sample assay in diagnosis of wood decay and to investigation
of environmental fungal populations.
Part of this article was presented at the International Symposium on Wood Science and Technology (IAWPC 2005), Yokohama, November
2005 相似文献
7.
Vignir Sigurdsson Kesara Anamthawat-Jónsson Adalsteinn Sigurgeirsson 《New Forests》1995,10(3):197-206
Nine trees from a single, natural population of black cottonwood (Populus trichocarpa Torr. et Gray) in Alaska were screened for randomly amplified polymorphic DNA (RAPD) markers with ten different 10-base random oligonucleotide primers in order to evaluate the use of RAPD analysis for distinguishing black cottonwood clones. Nine primers amplified the genomic DNA targets; two primers were able to differentiate all clones. Eight clones were distinguished among the nine tree samples assayed. Two trees showed identical banding patterns with all primers used; therefore it is suggested that these trees are from the same clone. The RAPD fingerprinting method is simple and powerful-one primer can distinguish different clones, while the use of multiple primers reduces fingerprint similarity and resolves discrepancies. 相似文献
8.
Liriodendron are ideal plants for research on mating system, systemic evolution and population genetics. Here we report the development
and application of a set of simple sequence repeat (SSR) markers derived from expressed sequence tags (ESTs) of L. tulipifera. In total, 176 primer pairs were developed and yielded 132 EST-SSR markers that amplified clear SSR bands with genomic DNA
of L. tulipifera. Transferability of these EST-SSR markers to related species and genera was further examined. Twelve highly informative loci
screened from 132 EST-SSR markers were applied to explore the effective pollen dispersal patterns and male reproductive success
of Liriodendron. A provenance trial population of Liriodendron comprised 12 L. chinense (Hemsl.) Sarg provenances and 5 L. tulipifera provenances. The four maternal trees were randomly sampled as tested maternal trees in the population. Paternities of 220
open-pollination progenies from 4 maternal trees above were potentially identified by means of paternity analysis, of which
138 progenies (accounting for 62.7%) were assigned to 49 male parents at the 95% confidence level. The cumulative exclusion
probability of 12 EST-SSR loci was 98.5%. The average effective pollen dispersal distance of pollen donors ranged from 15
to 35 m, with the maximum dispersal distance of 77 m. There were obvious male reproductive success differences among individuals,
ranging from 0 to 10.9%. The cumulative male reproductive success of individuals within 35 m radius around the known maternal
trees reached 51.4%. Diversiform mating patterns, including selfing, intra-species mating and interspecies mating, coexisted
in the occasion of open-pollination in Liriodendron. 相似文献
9.
Lophodermium seditiosum is a serious needle pathogen on pine, particularly in nurseries, and there is a need to detect the pathogen during its latent phase. The internal transcribed spacer (ITS) regions of the rDNA of L. seditiosum and L. pinastri were amplified with universal primers and sequenced. Sequence comparisons of the two species allowed the design of species‐specific primers for the ITS regions. The primers were between 18 and 24 bp long with a minimum of 3 bp differences between the species. These primer pairs did not give any amplification of DNA from any other of the examined fungal species or from healthy Pinus sylvestris needles. It was also possible to identify either L. seditiosum or L. pinastri in infected needles with and without signs of infection using these primer pairs. The method was found to be very useful for detection of latent infections of L. seditiosum in P. sylvestris needles in nurseries. 相似文献
10.
Germination tests are currently the most widely used method to evaluate seed quality of Ginkgo biloba L., but they are time-consuming and labor intensive. Oxygen-sensing technology, based on the principle of fluorescence quenching to detect oxygen and assess seed quality was used to rapidly evaluate seed quality of two varieties (Shandong Tancheng 202 and Zhejiang Dafoshou) of G. biloba from five mother plants. Fifteen samples of three vigor levels were produced by accelerated aging treatments. This process was applied in duplicate. A portable oxygen-sensing detector was employed to measure oxygen content during seed germination in a closed system at 25 °C each day until day 14. Four oxygen metabolism indices were calculated: oxygen consumption index, oxygen consumption rate, critical oxygen concentration, and theoretical germination time (T GT). Additionally, we tested laboratory germination and field emergence. The results of a one-way analysis of variance and correlation analysis showed that T GT was the candidate index to evaluate seed quality of G. biloba. Therefore, the T GT value was used to validate the reliability of oxygen-sensing evaluation for Zhejiang Dafoshou seeds kept under four storage conditions. The trend in the change in oxygen metabolism agreed completely agreement with that of seed germination under all storage conditions. The oxygen-sensing test reliably and rapidly assessed seed quality of G. biloba. The germination rate of Zhejiang Dafoshou was accurately predicted by T GT. 相似文献
11.
通过对山苍子幼嫩叶片、顶芽、花蕾3种组织的DNA提取效果分析和对影响酶切及选择性扩增效果的4个主要因素(酶切时间、Mg2+浓度、dNTPs浓度、引物浓度)的比较研究,建立了适合于山苍子AFLP分析的技术体系。结果表明,山苍子的顶芽是较好的DNA提取材料;山苍子基因组DNA经5 U EcoR I和5 U Mse I酶切1 h即可完全酶切;最佳的选择性扩增体系为20 μL反应体系中含有1.0 U rTaq聚合酶、2.0 μL 10×PCR缓冲液、1.8 μL 25 mmol·L-1MgCl2、1.4 μL 2.5 mmol·L-1dNTP、100 ng·μL-1引物各1.0 μL。使用该反应体系获得了清晰、稳定的DNA指纹图谱,并筛选出10对多态性较好的AFLP引物组合,为利用AFLP标记技术进一步开展山苍子种群遗传结构、遗传分化等研究奠定了基础。 相似文献
12.
Presymptomatic and accurate diagnoses of pathogens are essential for disease prediction and the timely application of bactericide. The bacterium Lonsdalea quercina (=Brenneria quercina) has been reported as the causal agent of drippy nut and bark canker disease on oak in California (US) and Europe. In recent years, it is also found on Populus × euramericana trees in Henan province of China. This bacterium causes longitudinal cankers of a few centimetres in size on the bark surface of the upper trunk. In this study, we developed two species‐specific PCR assays using primer pairs LqfF/LqfR and LqgF/LqgR for the rapid and accurate detection of the pathogenic bacteria in diseased plant tissues. The results show that the LqfF/LqfR primers amplified only a single PCR band of approximately 382 bp and the LqgF/LqgR primers yielded a PCR product of approximately 286 bp. The two primers were successfully adapted to real‐time PCR based on SYBR Green I used with the ABI 7500 system. The detection limit of the reaction was 0.1 pg genomic DNA per 20 μl PCR reaction volumes. The pathogen was mainly detected in the phloem of cankers as well as in the exudates of diseased trees, but was not found in the xylem or leaves. The size of pathogen in distribution was larger than the lesion. The results demonstrate that real‐time PCR assays can be used to detect the pathogen by extracting DNA directly from infected plant tissues. This method is a rapid, reliable method for the presymptomatic and accurate detection of L. quercina, providing a useful insight into epidemiological studies. 相似文献
13.
利用RACE技术从银杏中克隆到过氧化氢酶基因(GbCAT1)的cDNA全长。进化树分析结果表明:GbCAT1和其他物种的CAT源自于相同的祖先。Southern杂交显示:GbCAT1属于1个小的多基因家族。实时定量RT-PCR分析表明:GbCAT1在银杏的根、茎、叶和果中都有表达,在叶中的相对表达量最高,其次为果、茎和根。GbCAT1的转录受到ABA、渗透压、紫外、低温和高温胁迫的诱导。水杨酸处理下,GbCAT1相对表达量迅速降低。CAT1基因在逆境条件下的相对表达变化与环境胁迫有关。 相似文献
14.
Ferenc Lakatos Wojciech Grodzki Qing-He Zhang Christian Stauffer 《Journal of Forest Research》2007,12(5):345-349
The distribution of the double spined spruce engraver beetle Ips duplicatus ranges from Scandinavia and northeastern Europe to northern Asia. In Europe, I. duplicatus usually is associated with I. typographus on Picea abies, and due to morphological similarities and similar gallery constructions the damage and significance of I. duplicatus are often not recognised and thus underestimated. I. duplicatus has been recently reported from the southern part of Poland, the Czech Republic, Slovakia, northern parts of Austria and
Germany; records are missing from many other central European countries (e.g., Hungary). The species became an important pest
in some parts of central Europe, and continuous outbreaks of this bark beetle have been reported in Inner Mongolia, China,
since the 1950s. The aim of this study was to compare I. duplicatus populations from Europe and Asia by genetic means using the analysis of the mitochondrial DNA. Individuals of I. duplicatus populations from China, Poland, the Czech Republic and Slovakia were collected, and 520 bp fragments of the cytochrome oxidase I (COI) gene were analysed. Four haplotypes were detected and a sequence divergence of 0.8% was found between the populations
from China and Europe. These differences associate with behavioural differences in the pheromone bouquet and behavioural response
of the two groups. Within Europe three haplotypes were found, but due to the small sample size no significant geographical
distribution was demonstrated. 相似文献
15.
Zhi-peng Chen Jun Sun Hong-xuan Chen Yan-yu Xiao Dan Liu Jun Chen Hao Cai Bao-chang Cai 《Fitoterapia》2010,81(8):1045-1052
The aim of this study was to improve the oral bioavailability of Ginkgo biloba extract (GBE) through preparing G. biloba extract phospholipid complexes (GBP) and G. biloba extract solid dispersions (GBS). Firstly we prepared the GBP and GBS and studied their physicochemical properties by differential scanning calorimetry (DSC), powder X-ray diffraction (XRD) and dissolution. Then we studied the pharmacokinetic characteristics and bioavailability in rats. The results showed that the bioavailability of quercetin, kaempferol and isorhamnetin in rats was increased remarkably after oral administration of GBP and GBS comparing with GBE. The bioavailabilities of GBP increased more than that of GBS. 相似文献
16.
WANG Hui-mei ZU Yuan-gang 《林业研究》2007,18(4):316-318
UGPase gene related with wood cellulose synthesis was transferred into C. acuminata using the method of Agrobacte- rium-mediated genetic transformation, and an efficient transformation system was developed for C. acuminata on the basis of evaluations of several factors affecting Agrobacterium-mediated DNA transfer rate. The highest transformation rate was achieved when pre-cultttred leaf explants were infected with an Agrobacterium culture corresponding to OD600 （0.5） for 10 min, and cultured on explant regeneration medium for three days. The results of Southern hybridization showed that genomic DNA of the kanamycin-resistant shoots to an UGPase gene probe substantiated the integration of the transgene. Transformation efficiency （6%） was achieved under the optimized transformation procedure, This system should facilitate the introduction of important useful genes into C, acuminata. 相似文献
17.
[目的]研究不同道路防护林的滞尘能力及滞尘的动态变化和空间分布规律。[方法]在春季对3种道路防护林(油松林、圆柏林、银杏林)距道路不同宽度的滞尘量进行连续观测,对比3种道路防护林滞尘能力,分析降雨、极大风速、相对湿度、PM10等因子对滞尘动态的影响以及3种道路防护林滞尘的空间分布特征。使用单位叶干质量滞尘量(mg·g-1)表征叶面滞尘能力。[结果]表明:(1)3种植物叶面滞尘能力差异显著,圆柏银杏油松,分别为4.79±0.20、2.48±0.07、1.42±0.04 mg·g-1,单株和单位林分面积滞尘量均为圆柏林油松林银杏林;(2)3种道路防护林在外界影响下滞尘量处于动态变化之中,油松林具有比银杏和圆柏林更高的滞尘稳定性;(3)降雨量较低时3种道路防护林滞尘量均增加,降雨量较高时3种道路防护林滞尘量均降低,油松和银杏林的滞尘量更容易受降雨影响而降低;随着风速增大,3种道路防护林滞尘作用不断加强,风速继续增大时,油松和圆柏林滞尘量均有减少,银杏林滞尘量仍有显著增加。(4)3种道路防护林滞尘量在五环路侧(北)均高于香山路侧(南),油松和圆柏林均呈现为道路防护林中间位置为最低点,银杏林中间位置滞尘量最高。(5)油松和圆柏林滞尘量外部比内部变化大,银杏林滞尘量内部比外部变化大。[结论]道路防护林的滞尘效益受树种、林分结构、所处环境、天气条件等多方面因素共同影响,在营建和管理过程中应充分考虑各种因素,充分发挥滞尘作用。 相似文献
18.
DNA was extracted from wood samples of six representativeCyclobalanopsis species (Fagaceae) growing in Japan that cannot be distinguished from one another by conventional microscopy. A part of the intergenic spacer region betweentrnT andtrnT 5 exon was amplified and sequenced. The sequences obtained from wood samples were grouped into three DNA types by a single nucleotide polymorphism as reported previously in leaf samples: I (Quercus acuta, Q. sessilifolia, Q. salicina), II (Q. myrsinaefolia, Q. glauca), and III (Q. gilva). Thus,Q. gilva can be distinguished from the otherQuercus species, and the others are separated in two subgroups based on DNA polymorphism. The present findings support the possibility of wood identification based on DNA polymorphism. 相似文献
19.
A loop‐mediated isothermal amplification‐based method for detecting Bursaphelenchus xylophilus from Monochamus alternatus 
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下载免费PDF全文 The introduction of the pine wood nematode (PWN), Bursaphelenchus xylophilus, to new areas has impacted on the international economy. Therefore, accurate and reliable detection methods for PWN are essential for the control and management of this pest. A rapid and economic method for detecting PWN may be developed focusing on the PWN vector (Monochamus alternatus). This work standardized a loop‐mediated isothermal amplification (LAMP) method using newly designed primer sequences based on the syg‐2 gene, which encodes the synaptogenesis protein syg‐2. Loop‐mediated isothermal amplification was conducted at 63°C for 60 min using six sets of primers. The result was confirmed by visual observation. A positive reaction was confirmed by SYBR Green I fluorescence dye under light thermal cycling. The lower limit of DNA detection was 51.4 pg/μl in both LAMP and 51.4 ng/μl in PCR. Therefore, the LAMP was 1,000 times more sensitive in DNA detection than PCR. The LAMP is a relatively new, highly accurate and rapid molecular technique that can rapidly detect infectious agents in the field without requiring sophisticated instruments, giving a visually readable result. The method greatly improves detection, without requiring professional knowledge and expensive, sophisticated equipment. Therefore, this system is suitable for quarantine and field detection. 相似文献
20.
The Cydia pomonella granulovirus (CpGV) is a very effective biological control agent of the codling moth, Cydia pomonella L. (Lep.: Tortricidae). Only a few CpGV isolates originating from Mexico (M), England (E), and Russia (R) have been described
so far. In a field survey at different locations in Iran, CpGV isolates were collected from single or pooled codling moth
larvae. The isolates, designated I1, I7, I8, I15, I22, I28, I30, I66, I67, I68, and I70 showed genetic (DNA restriction endonuclease
profiles) and biological (bioassays) differences. Most isolates could be attributed to genome types similar to those found
in CpGV-M, -E, and -R. Some of them were clear mixtures of different genotypes. Thus, the CpGV isolates found in the North–West
of Iran make an important contribution to the known diversity of CpGV. The occurrence of novel, naturally occurring CpGV isolates
emphasize the necessity of further studies towards the diversity and evolution of CpGV. 相似文献