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1.
作物核心种质是用最小的样本代表其全部遗传资源的最大遗传多样性。为了检测大豆初选核心样本取样的代表性,本研究从黄淮夏大豆初选核心样本中,随机选取两个类群,其材料数分别为20份和14份;从保留种质的相应奥群中,分别随机选取6份和5份,共计45份材料,进行14个农艺性状和20对SSR引物的分析。对两组材料进行农艺性状聚类.保菌种质与初选核心种质聚在了一起;利用SSR分子标记数据聚类,也得到了相同的结果。初选核心样本两个类群材料的等位变异数分别为129个,136个;保留种质相应类群材料的等位变异分别为76个,71个;初选核心种质两个类群材料分别包合了整个资源86.00%和86.62%的遗传多样性。本研究为大豆核心种质构建及检测提供分子水平的依据。  相似文献   

2.
Methods of developing a core collection of annual Medicago species   总被引:1,自引:0,他引:1  
A core collection is a subset of a large germplasm collection that contains accessions chosen to represent the genetic variability of the germplasm collection. The purpose of the core collection is to improve management and use of a germplasm collection. Core collections are usually assembled by grouping accessions and selecting from within these groups. The objective of this study was to compare 11 methods of assembling a core collection of the U.S. National collection of annual Medicago species. These methods differed in their use of passport and evaluation data as well as their selection strategy. Another objective was to compare core collections with sample sizes of 5%, 10% and 17% of the germplasm collection. Core collections assembled with evaluation data and cluster analysis better represented the germplasm collection than core collections assembled based solely on passport data and random selection of accessions, The Relative Diversity and the logarithm methods generated better core collections than the proportional method. The 5% and 10% sample size core collection were judged insufficient to represent the germplasm collection.  相似文献   

3.
利用表型数据构建陆地棉核心种质   总被引:3,自引:0,他引:3  
以5963份陆地棉种质资源为材料,根据品种主要突变性状和品种类型分组成11组群,在分组的基础上利用21个表型性状,用非加权类平均聚类分析法,构建了281份陆地棉核心种质,占全部种质资源总量的4.71%。利用不同性状的均值t测验、方差F测验、变异系数、多样性指数t检验、均值、极差、表型方差、变异系数、均值差异百分率、方差差异百分率、极差符合率、变异系数变化率、主成分分析等参数进行核心种质代表性检验和评价。结果表明,所构建的陆地棉核心种质可以代表全部种质的遗传多样性。  相似文献   

4.
目的回顾性分析影响脐带血采集质量的母婴因素和采集处理因素。 方法记录389份脐带血的采集量、母亲年龄、孕龄、新生儿体重、分娩方式、新生儿性别、胎次及脐带血采集至计数间隔以及采集方式。用KX-21型全自动血液分析仪进行细胞计数并计算有核细胞总数(TNC)。采用Pearson相关和Spearman秩相关进行相关性分析,采用t检验、Mann-Whitney U检验、方差分析及Kruskal-Wallis H检验进行分组比较,分析影响脐带血采集量和TNC的相关因素。? 结果脐带血采集量与TNC显著相关(r = 0.723,P < 0.001),脐带血采集量大于80 ml时的TNC显著高于低体积者。在母婴因素中,母亲年龄与采集量及TNC差异均无统计学意义;孕龄与采集量负相关(r = -0.119,P = 0.019),而与TNC正相关(r = 0.138,P = 0.007),足月儿脐带血的TNC显著高于早产儿(P = 0.038);婴儿出生体重与采集量及TNC均正相关(r = 0.236,P < 0.001;r = 0.275,P < 0.001),体重较大婴儿脐带血的采集量和TNC均显著高于体重较小者(P?< 0.001);剖宫产的脐带血采集量虽高于阴道分娩(P < 0.001),但其TNC不及阴道分娩;男婴与女婴在脐带血采集量和TNC之间无显著差异。在采集处理因素中,脐带血采集至计数的时间间隔与采集量及TNC均无显著相关。 结论为提高脐带血的保存质量,应侧重选择胎儿体重较大、经阴道分娩的产妇作为脐带血供者,实验室应首先处理采集量较大的脐带血。  相似文献   

5.
基于AFLP分子标记的桂花品种核心种质的构建   总被引:1,自引:0,他引:1  
用100个桂花品种荧光AFLP分子标记信息构建核心种质。利用获得的指纹信息,运用UPGMA聚类取样法,采用Kimura 2-parameter遗传距离,多次聚类随机抽样。结果表明:(1)8对引物共获得514条带,平均每对引物获得64条带。(2)从100个桂花品种中筛选了30个样本的核心种质。(3)比较核心种质和全部种质的Shan-non-Wiener指数(H′)和Simpson指数(D),t检验值均说明核心种质的遗传多样性指数与全部种质遗传多样性没有明显差异,表明所构建的核心样品能够很好地保留原始100个桂花品种的遗传多样性。  相似文献   

6.
上海辰山植物园于2005年开始筹建,与此同时启动了的植物收集工作。本文就辰山植物园基本情况、植物收集中长远规划、进展及技术策略进行了论述。活植物收集和标本收集是辰山植物园植物收集工作的两个方面。活植物收集包括以华东植物区系植物为主的物种收集和以上海适生的观赏植物为主的园艺品种收集,如鸢尾属、绣球属、荚蒾属、锦带属和绣线菊属的观赏园艺品种。截止到2010年,辰山植物园共收集了9000种和园艺品种。其中,华东植物区系物种有1700种,来自世界范围专业苗圃的园艺品种有2800个,另有4500种和品种是种植于温室的热带和亚热带植物。目前共收集了近10000份标本,多数为研究和活植物收集的凭证标本,全部存放于上海辰山植物园标本馆(CSH)。  相似文献   

7.
上海辰山植物园于2005年开始筹建,与此同时启动了的植物收集工作。本文就辰山植物园基本情况、植物收集中长远规划、进展及技术策略进行了论述。活植物收集和标本收集是辰山植物园植物收集工作的两个方面。活植物收集包括以华东植物区系植物为主的物种收集和以上海适生的观赏植物为主的园艺品种收集,如鸢尾属、绣球属、荚蓬属、锦带属和绣线菊属的舭赏园艺品种。截止到2010年,辰山植物园共收集了9000种和园艺品种。其中,华东植物区系物种有1700种,来自世界范围专业苗圃的园艺品种有2800个,另有4500种和品种是种植于温室的热带和亚热带植物。目前共收集了近10000份标本,多数为研究和活植物收集的凭证标本,全部存放于上海辰山植物园标本馆(CSH)。  相似文献   

8.
为尽快明确天然林中蒜头果种质资源收集保存的策略和目标,本研究基于21个表型及经济性状,构建蒜头果核心种质,明确了建立蒜头果育种和保存群体的目标材料,为其资源保育提供依据。在系统聚类和优先取样法的基础上,分别利用遗传多样性法、比例法和对数法,设定10%、20%和30%3种取样比例,产生7种构建策略;采用8个参数评价7种策略构建的核心种质,得到参数最优的核心种质;采用4重方法验证核心种质的有效性和代表性。结果表明,(1)“优先取样法+遗传多样性法+30%取样比例”形成的核心种质,8个评价参数最优,核心种质包含28个样本,取样比例为28.87%。(2)4种验证方法均表明,构建的核心种质具有较好的代表性。多样性指数的t检验表明,核心种质与原种质在21个性状上的多样性指数差异均不显著(0.05);符合率检验表明,核心种质与原种质在21个性状上的均值、极大值、极小值和多样性指数的符合率均在80%以上;主成分检验表明,核心种质与原种质具有相近的特征值、贡献率和累计贡献率;核心种质与原种质的样品分布表明,两者具有相似的分布结构。研究认为,构建的蒜头果核心种质具备代表性、有效性和实用性等特征,可作为蒜头果种质资源收集保存和建立育种群体的依据。  相似文献   

9.
Blood sampling is often critical for answering a variety of questions about wild birds. However, it is important to assess the impacts, if any, of blood collection on wild birds. Here, we examined the effects of blood sampling on adults or nestlings in three species of free-living birds. First, we examined the effects of blood collection on annual survival and reproductive success in adult buff-breasted wrens Thryothorus leucotis in Panama. In adult wrens, blood collection from the brachial vein during the breeding season had no effect on annual survival or reproductive success. Second, we examined whether blood collection influenced mass gain in developing smooth-billed anis Crotophaga ani in Puerto Rico. In developing anis, blood collection from the femoral or jugular veins had no effect on mass gain of nestlings. Third, in developing European starlings Sturnus vulgaris in British Columbia, Canada, blood collection from the brachial vein had no effect of body condition. Blood collection from the jugular vein had a transient effect on body condition during the first week post-hatch, but this effect disappeared by the second week of age. Lastly, we present an extensive up-to-date review of the literature on the effects of blood collection on free-living avian species. Taken together, these data show that blood collection has no major negative effects on developing or adult birds in the wild.  相似文献   

10.
The role of fluid flow in the elutriation process was visualized by pumping dye solution through the Beckman JE-6 elutriator rotor. Three major fluid flow disturbances were observed in the separation chambers, namely; jet-streaming, ripple flow, and whirl flow. In order to evaluate the effects of these non-ideal fluid flow patterns on the separation of homogeneous populations of particles or cells, 12--35 micron diameter latex spheres and 9L rat brain tumor cells were fractionated with the Beckman elutriator system. The elutriator system was evaluated on the basis of: (1) recovery, (2) elution loss during loading, (3) homogeneity of the size distributions, and (4) the relationship of the median volume of eluted particles or cells to the rotor speed and the collection fluid velocity. Both a conventional collection method (two 40-mL fractions at ech collection rotor speed) and a long collection method (10--15 40-mL fractions at several collection rotor speeds) were compared to determine if collection procedures could compensate for some of the difficulties caused by the non-ideal fluid flow patterns. Although more than 90% of the particles or cells were always recovered, about 5% eluted during the loading procedure. Neither collection method altered this phenomenon. The long collection method significantly improved the homogeneity of the collected populations, but this was accompanied by a reduction in cell yield. The median particle or cell volume of each fraction agreed with that expected under ideal fluid flow conditions except at high and low rotor speeds when the conventional collection method was used.  相似文献   

11.
AIMS: To provide evidence that DNA-PCR diagnostics of oral pathogens based on standard sample collection by paper point insertion from the depth of the periodontal pocket can be replaced by a novel non-invasive collection method based on swab technique from the gingiva. METHODS AND RESULTS: In this study we compared the results from two collection methods performed in 35 patients with chronic adult periodontitis. Statistical analysis showed a highly significant association of diagnostic results between both collection techniques. CONCLUSIONS: The Pocket-out method represents a reliable alternative to the standard collection technique for PCR diagnosis of oral pathogens. SIGNIFICANCE AND IMPACT OF THE STUDY: Due to its simplicity and non-invasiveness, the Pocket-out collection could be performed in any physician office, or even by the patient himself. With respect to the putative association between periodontal disease and various systemic illnesses, this method could be integrated with various screening programs of oral pathogens.  相似文献   

12.
OBJECTIVE: To compare the efficacy of two sputum collection techniques in patients with chronic obstructive pulmonary disease (COPD) in order to diagnose dysplasia or neoplasia. STUDY DESIGN: This was a crossover study design comparing induced sputum with sputum collected at home. One hundred seven patients with COPD were enrolled. Fifty-six were randomized to collect induced sputum first followed by sputum collection at home. Fifty-one randomly assigned patients collected the sputum in reverse order. RESULTS: The second sputum collection technique for both random assignments gave the greatest yield of adequate sputum. There was no significant difference in efficacy between the collection of the two sputum collection techniques in the presence of the learning (period) effect. CONCLUSION: Sputum collection is equally efficacious by the induced method and the home collection method. A learning effect was responsible for the increased yield of sputum abnormalities in the second collection session. Sputum collection at home may facilitate the amount of dysplasic and neoplastic bronchial epithelial changes in heavy smokers with COPD.  相似文献   

13.
Aims: Having and executing a well-defined and validated sampling protocol is critical following a purposeful release of a biological agent for response and recovery activities, for clinical and epidemiological analysis and for forensic purposes. The objective of this study was to address the need for validated sampling and analysis methods called out by the General Accounting Office and others to systematically compare the collection efficiency of various swabs and wipes for collection of bacterial endospores from five different surfaces, both porous and nonporous. This study was also designed to test the collection and extraction solutions used for endospore recovery from swabs and wipes. Methods and Results: Eight collection tools, five swabs and three wipes, were used. Three collection/preservation solutions were evaluated: an ink jet aerosol generator was used to apply Bacillus subtilis endospores to five porous and nonporous surfaces. The collection efficiencies of the swabs and wipes were compared using a statistical multiple comparison analysis. Conclusions: The ScottPure® wipe had the highest collection efficiency and phosphate-buffered saline (PBST) with 0·3% Tween was the best collection solution of those tested. Significance and Impact of the Study: Validated sampling for potential biological warfare is of significant importance and this study answered some relevant questions.  相似文献   

14.
以中国花生种质资源数据库中记录的6390份花生资源为材料,以其基本数据、特征数据和评价数据为信息,采用分层、层内分组聚类以及随机取样与必选资源相结合的方法,构建了由576份资源组成的花生核心种质,占基础收集品的9.01%。对核心种质的植物学类型组成和遗传多样性指数的分析,以及对各性状特征值、符合率和包含的主要抗病资源抗性等级及重要农艺性状资源的检测结果表明,本研究建立的核心种质是有效的。基础收集品中各种性状的遗传变异在核心种质中均存在,所用15个性状的各种特征值符合率均在90%以上,其中绝大部分性状的符合率达96%以上。  相似文献   

15.
中国花生核心种质的建立   总被引:4,自引:0,他引:4  
以中国花生种质资源数据库中记录的6390份花生资源为材料,以其基本数据、特征数据和评价数据为信息,采用分层、层内分组聚类以及随机取样与必选资源相结合的方法,构建了由576份资源组成的花生核心种质,占基础收集品的9.01%。对核心种质的植物学类型组成和遗传多样性指数的分析,以及对各性状特征值、符合率和包含的主要抗病资源抗性等级及重要农艺性状资源的检测结果表明,本研究建立的核心种质是有效的。基础收集品中各种性状的遗传变异在核心种质中均存在,所用15个性状的各种特征值符合率均在90%以上,其中绝大部分性状的符合率达96%以上。  相似文献   

16.
The Embryo Collection of the Hubrecht Laboratory is a treasure house of comparative embryology. It is the largest and most important collection of its kind in the world, and consists of thousands of vertebrate embryos stored in alcohol, or prepared as histological sections. Many elusive species are included in the collection, some represented by complete developmental series. The accompanying archives offer a remarkable insight into the methods used to collect embryos form wild animals, as well as the motives behind the founders of the collection. Carefully maintained, documented and catalogued, the collection is available for study by all interested scientists. We argue that this collection is one of the greatest biodiversity resources in existence.  相似文献   

17.
园艺作物核心种质构建的研究进展   总被引:1,自引:0,他引:1  
构建核心种质是植物遗传资源的研究热点和重点之一,对种质资源的鉴定、保存、利用与交流具有重要意义。本文简要介绍了植物遗传资源核心种质的概念及其构建方法,综述了园艺作物核心种质构建的研究新进展,并对今后该领域的研究趋势进行了展望。提出了种质分组及取样策略是园艺作物核心种质构建方法研究的重点;应及时构建一批大宗园艺作物以及我国原产和特产园艺作物的核心种质;高度重视基于重测序技术快速、精准、高通量地挖掘园艺作物核心种质优异基因的研究以及要加强科研管理与协作,切实提高我国园艺作物核心种质研究成果的共享性等观点,为园艺作物种质资源的深入研究与高效利用提供理论依据和技术参考。  相似文献   

18.
The role of fluid flow in the elutriation process was visualized by pumping dye solution through the Beckman JE-6 elutriator rotor. Three major fluid flow disturbances were observed in the separation chambers, namely; jet-streaming, ripple flow, and whirl flow. In order to evaluate the effects of these non-ideal fluid flow patterns on the separation of homogeneous populations of particles or cells, 12–35 μm diameter latex spheres and 9L rat brain tumor cells were fractionated with the Beckman elutriator system. The elutriator system was evaluated on the basis of: (1) recovery, (2) elution loss during loading, (3) homogeneity of the size distributions, and (4) the relationship of the median volume of eluted particles or cells to the rotor speed and the collection fluid velocity. Both a conventional collection method (two 40-mL fractions at each collection rotor speed) and a long collection method (10–15 40-mL fractions at several collection rotor speeds) were compared to determine if collection procedures could compensate for some of the difficulties caused by the non-ideal fluid flow patterns. Although more than 90% of the particles or cells were always recovered, about 5% eluted during the loading procedure. Neither collection method altered this phenomenon. The collected populations, but this was accompanied by a reduction in cell yield. The median particle or cell volume of each fraction agreed with that expected under ideal fluid flow conditions except at high and low rotor speeds when the conventional collection method was used.  相似文献   

19.
The purpose of this inter-species comparison (calves and pigs) was to identify methodological and biological influences on the collection and composition of exhaled breath condensate (EBC). A total of 352 EBC samples were collected, whilst variables of ventilation were registered in parallel. Partial pressure of carbon dioxide (pCO2) and pH were analysed in non-degassed EBC samples. The concentration of total protein in EBC was measured colorimetrically. In both species, lung function was evaluated before and after EBC collection. Statistical analyses were performed to study the effect of EBC collection on lung function and to identify the influence of ventilatory variables on the collection and composition of EBC. Collection of EBC did not affect lung function. Despite the volume of EBC collected per unit time being primarily dependent on ventilation per unit time, species-specific conditions during the EBC collection process resulted in different dependences of EBC collection from other variables of ventilation (i.e. maximal airflow during expiration or expired tidal volume kg-1 body weight). The concentration of protein ml-1 EBC increased with the expired volume per min and with peak expiratory flow. Although the pCO2 in fresh EBC was significantly negatively dependent on the duration of collection, comparable pHs (5.6 - 6.2) were measured in EBC of both calves and pigs. The obtained data may help one standardize EBC collection in different species.  相似文献   

20.
More than 90% of the breeding stock of Austrian dual purpose Simmental cows is artificially inseminated. Knowledge of factors affecting sperm production and semen quality is of importance with regard to reproductive efficiency and thus genetic improvement as well as for the productivity and profitability of AI centers. Hence, semen data from two Austrian AI centres collected in the years 2000 and 2001 were evaluated. In total, 3625 and 3654 ejaculates from 147 and 127 AI bulls, respectively, were analysed regarding ejaculate volume, sperm concentration, percentage of viable spermatozoa in the ejaculate, total spermatozoa per ejaculate and motility. Effects accounted for were the bull (random), age of bull, collection interval, number of collection on collection day, bull handler, semen collector, temperature on day of semen collection, in the course of epididymal maturation (average temperature of days 1-11 before collection) and during spermatogenesis (average temperature of days 12-65 before collection). Age of bull significantly affected all traits (P<0.01 to P<0.001) except motility score in center 2. Ejaculate volume and total number of spermatozoa increased with age of bull while sperm concentration was lower in higher age classes (center 1). The collection team was also found to significantly influence semen quality traits. With increasing collection interval ejaculate volume and total number of spermatozoa increased significantly (P<0.05 to P<0.001) while collection intervals between 4-9 days and 1-6 days were superior with regard to sperm concentration and percentage of viable spermatozoa, respectively (P<0.10 to P<0.001). First ejaculates were superior with respect to ejaculate volumes, sperm concentrations and total number of spermatozoa per ejaculate (P<0.001). Temperature, either on day of semen collection or during epididymal maturation or spermatogenesis, had important but inconsistent effects on semen production and sperm quality. Overall, however, ambient temperatures in the range of 5-15 degrees C were found to be optimal for semen production.  相似文献   

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