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51.
为研究玉米(Zeamays L.)19kD醇溶贮藏蛋白(zein)基因启动子种子特异性表达的控制区段,将全长694bp的启动子进行5’端缺失,共得到6个缺失突变体,长度分别为488bp、378bp、302bp、152bp、124bp和85bp。将6个片段分别与报告基因gus连接构建成表达载体pDGB系列,经土壤农杆菌(Agrobacterium)介导转化,引入烟草。GUS活性检测证明,488bp启动子片段能促使gus基因在种子中特异表达。378bp、302bp、152bp和124bp片段启动子引导的gus基因在烟草根、叶柄、种子中均可表达。  相似文献   
52.
【目的】为检验直接分子检测法用于揭示杜鹃花属(Rhododendron)植物根部真菌(Root-associated fungi,RAF)组成的有效性。【方法】采用不依赖于培养的分子检测技术直接从锈红杜鹃(R.bureavii)与薄叶马银花(R.leptothrium)的发根(Hair root)提取DNA,用真菌特异性引物扩增r DNA-ITS区、经克隆后测序,对获得的ITS序列进行分析;通过收集NCBI中与本研究的RAF相似性97%以上的所有序列对应的真菌来源(土壤或根系的身份)数据,分析真菌的生态学特性,并用FUNGuild软件提供的方法划分真菌的生态类型。【结果】从两种杜鹃花根部共检测到15种真菌,其中担子菌门(Basdiomycota)真菌3种,子囊菌门(Ascomycota)真菌12种。柔膜菌目(Helotiales)真菌在两种杜鹃花RAF群落中占据优势,并且在两种杜鹃花根系中均检测到该类真菌。此外,两种杜鹃花根部有多种生态类型的RAF共存,包括曾被频繁报道的杜鹃花类菌根菌Oidiodendron sp.和Rhizoscyphus sp.、内生真菌Phialocephala fortinii、共生一致病过渡型真菌Pezoloma ericae、外生菌根共生菌Meliniomyces sp.,以及腐生型真菌Myceana sp.、Lachnum virgineum、Herpotrichia sp.。【结论】直接分子检测法从两种杜鹃花属植物根部检测到的真菌谱系多样性较高、生态类型复杂,这一方法能较为全面地反映杜鹃花属植物RAF多样性。  相似文献   
53.
New systematic conservation approaches have high potential in evaluation of different conservation scenarios and can be used as decision support tools for managers and planners with multiple goals. The present study focused on two major issues in conservation planning including socioeconomic costs and zoning procedure. The goal was to prioritize and identify representative areas for bird conservation, while minimizing the economic cost for the silvicultural sector and resolve conflicts with recreational activities. The study was conducted in forest areas of Golestan Province as part of Hyrcanian mixed forests, located along the southern coasts of the Caspian Sea and northern slopes of the Alborz Mountains, northern Iran. We used systematic conservation software Marxan with Zones to select candidate areas for conservation. Two types of conservation networks were defined, one with high and partial protection zones and the other with high protection zones only. We focused on four conservation scenarios varying in targets, costs, and multiple zones. The results showed that incorporation of socioeconomic costs significantly decreases the potential impacts on the silvicultural and recreational sectors without significant change in the area of protection zones. Furthermore, we found that design of multiple zone conservation areas facilitates evaluation of a wider range of conservation scenarios that can reduce potential socioeconomic impacts on other interests.  相似文献   
54.
为了检验已记录的4个溞属种类((隆线溞Daphnia carinata、透明溞D. hyalina、蚤状溞D. pulex和大型溞D. magna)的系统分类, 用试剂盒法分别提取4种溞类的基因组DNA。利用特异性引物, 通过PCR扩增了4种溞属种类的16S rDNA和COⅠ基因部分序列, 并与来自GenBank中每个种类相似度较高的同种序列进行分析。结果表明, 基于16S rDNA和COⅠ基因, 4个溞属种类的平均种间相似度分别为85.56%和80.67%, 碱基中A+T含量均明显高于G+C含量。基于COⅠ基因, 巢湖隆线溞与来自GenBank上的拟同形溞((Daphnia similoides AB549199))相似度为99%, 分歧度为0.4%0.9%。就16S rDNA和COⅠ基因而言, 巢湖透明溞更接近于盔形溞(Daphnia galeata)。基于16S rDNA和COⅠ基因构建的NJ树和贝叶斯树, 两者的主要分枝基本一致。结果暗示, 巢湖隆线溞与拟同形溞为一个种, 透明溞应属于盔形溞。由于缺乏核基因的研究, 有关巢湖溞属的分类地位还需进行更深入的探讨。    相似文献   
55.
With only five protected areas dedicated to the conservation of biodiversity (two national parks, one strict nature reserve and two faunal reserves), Guinea has one of the smallest protected area networks in West Africa. As a result, two of the five ecoregions of the country and six of the 14 globally threatened large and medium-sized mammals occurring in Guinea are not found in the national protected area network. To identify areas with high biodiversity that could be included in the national protected area network, we used the Key Biodiversity Areas (KBA) methodology. We devised a scoring system to rank the identified KBAs according to their relative conservation significance. We identified a total of 16 KBAs throughout the country. Their proclamation as protected areas would result in the protection of all ecoregions and all but one of Guinea’s globally threatened large and medium-sized mammals. Twelve of the 16 KBAs have the legal status of classified forest, a status that should facilitate the change into formal biodiversity protected areas (IUCN category I–IV). Our analysis indicates that even if only the two areas with the highest conservation significance score, the Ziama and Diécké forests, become formal protected areas, this would provide protection to both the western Guinean lowland forests, one of the most threatened ecoregions in Africa, and to 11 of the 14 threatened large and medium-sized mammals occurring in Guinea.  相似文献   
56.
Conservation projects may be reluctant to attempt Systematic Conservation Planning because existing methods are often prohibitive in the time, money, data, and expertise they require. We tried to develop a “resource light” method for Systematic Conservation Planning and applied it to the Ewaso Ngiro Landscape of central Kenya. Over a 6-month preparation period and 1-week participatory workshop, we used expert assessments to select focal biodiversity features, set quantitative targets for these, map their current distribution, vulnerability, potential for recovery, and conservation costs, and, finally, map cross-feature conservation priorities. Preparation for and facilitation of the workshop required time investment by one part-time workshop coordinator, eight workshop committee members, six ecosystem experts, and two GIS technicians. Total time investment was approximately 56.5 person-weeks spread over facilitators and 40 workshop participants. Monetary costs for the workshop were approximately $US 42,000, excluding investments made by researchers previous to this project. Costs for a similar workshop could vary substantially, depending on need to cover salaries, international travel, food and lodging, and the number of participants. To stay within our resource constraints, we completed the exercise for only four of nine focal biodiversity features and did not negotiate trade-offs between conservation and human land-uses or use planning software to identify “optimal networks” of conservation areas. These were not considered critical for conservationists to try Systematic Conservation Planning, introduce landscape-scale conservation concepts to stakeholders, and begin implementing landscape conservation strategies. Participants agreed that further work would be needed to complete and update the planning process. Due to the lack of comparative cost data from similar planning exercises, we cannot definitively conclude that our approach was “resource light”, although we suspect it is within the constraints of most site-based conservation projects.  相似文献   
57.
The systematic studies of the Ophiopogoneae in Asparagaceae were reviewed in respect of morphology, anatomy, micromorphology, cytology, molecular phylogenetics, biogeography, genome size, and exploiting and utilizing of plant resource, to provide reference for further studies on Ophiopongoneae.  相似文献   
58.
The shoulder is inherently an unstable joint which heavily relies on the neuromuscular activation of the rotator cuff (RC) complex for stability during movement. Currently, there is no consensus regarding how the activity of RC muscles is affected among individuals with a RC tendinopathy (RCTe). This study reviewed the evidence of studies comparing the electromyographic (EMG) activity of any RC muscle of shoulders with a symptomatic RCTe to asymptomatic shoulders. Eight databases were searched. Data from 343 participants (201 symptomatic and 209 asymptomatic shoulders) were analyzed from 10 out of 402 included studies. Strong evidence for the infraspinatus and supraspinatus during isometric contractions and limited evidence for the supraspinatus and infraspinatus during isokinetic contractions suggest that the muscular activity is not altered among individuals with a RCTe during these types of contraction. Very limited evidence indicates reduced muscle activity for the infraspinatus and subscapularis in the presence of a RCTe during isotonic contractions, and no alterations for the supraspinatus or teres minor were identified. Lastly, conflicting to moderate evidence suggests alterations in RC muscle activity during unrestrained movements and swimming. These findings indicate that EMG deficits associated with a RCTe can best be appreciated during unrestrained movements.  相似文献   
59.
A systematic approach for prioritization of protected areas is the use of artificial intelligence. This approach employs computer algorithms based on an objective function to identify the best network of areas to be protected. Site selection algorithms are commonly used to identify areas of high conservation value. This study used three types of heuristic algorithms (simulated annealing, greedy, rarity) to prioritize areas for protection in Mazandaran Province of Iran using Marxan software. The goal was to select a conservation network with the smallest possible area in which maximum protection targets are achievable. The effects of spatial scale, algorithm, and zone compactness were also examined. We found that the existing network of protected areas is inadequate to achieve conservation targets. The algorithm results provided the best areas for supplementation of the current network. The simulated annealing algorithm provided the most plausible results for all scenarios. These results can be used to modify the existing boundaries of the protected areas network and introduce new sites for protection of plant and animal species.  相似文献   
60.
通过对云南热带、亚热带生长的256种蕨类植物VA菌根的调查,发现蕨类植物VA菌根营养者所占的比例低于被子植物;在真蕨类植物中,植物具有由VA菌根营养经兼性VA菌根营养向自养方向进化的趋势。  相似文献   
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