安徽黄山西部青冈种群小地理范围的遗传分化

采用垂直板型聚丙烯酰胺凝胶电泳研究了黄山西部青冈〔Ｃｙｃｌｏｂａｌａｎｏｐｓｉｓｇｌａｕｃａ（Ｔｈｕｎｂ．）Ｏｅｒｓｔ．〕种群小地理范围的遗传分化。黄山２个亚种群之间基因频率基本没有差异,基因多样性平均为０．１８２６,小岭和钓桥亚种群分别有２个和１个位点存在显著的杂合子不足的现象。亚种群之间的遗传分化程度很低（ＧＳＴ＝０．９７６％）,主要是由于小地理范围的生境异质性程度低和较大的基因流（平均为１７３）造成的。     

马尾松天然群体同工酶遗传变异

６个马尾松天然群体同工酶分析结果表明：马尾松群体具有较丰富的遗传变异,其多态位点百分率（Ｐ）＝７６．２％;等位基因平均数（Ｎａ）＝２．３９;有效等位基因平均数（Ｎｅ）＝１．６２,平均杂合率（Ｈｅ）＝０．２７３。但群体间遗传分化极小,基因分化系数（Ｇ＿（ＳＴ））＝０．０１７２,遗传距离（Ｄ）＝０．０１１±０．００５。总遗传变异中,约２％来自群体间,而约９８％的遗传变异存在于群体内的个体,并且其变异又主要来源于１／３的基因位点。马尾松群体近似于随机交配群体,绝大多数位点处于平衡状况,但也有约１／３的位点并非随机交配,存在不同程度的近交。     

华东地区青冈种群的等位酶变异

华东地区６个青岗种群等位酶变异的检测结果表明,青冈种群的遗传变异较大,每位点含有的等位基因较多,平均为２．３个,种水平的平均每位点等位基因数目为２．４。种群水平有效等位基因数目为１．４４６,种水平为１．４６７。Ｈａｒｄｙ－Ｗｅｉｎｂｅｒｇ平衡检验表明,青冈种群中不少位点偏离该平衡,其原因是种群内含有较多的纯合子,表现为多数位点的固定指数大于０,其中有９个位点的固定指数与０的偏差达到显著水平。     

在韩国境内Potentilla fragarioides var.sprengeliana的遗传多样 …

根据２２个等位酶位点遗传变异,探讨了韩国境内委陵菜（Ｐｏｔｅｎｔｉｌｌａ ｆｒａｇａｒｉｏｉｄｅｓ Ｌ．ｖａｒ．ｓｐｒｅｎｇｅｌｉａｎａ）的遗传多样性和种群结构。酶位点的多态位点百分比为５９．１％。种和种群水平上的遗传多样性比较高,分别为Ｈｅｓ＝０．２１０,Ｈｅｐ＝０．１９９;而种群的分化水平则相对较低（ＧＳＴ＝０．０７４）。１９个种群中随机交配的偏差为ＦＩＳ＝０．３３１。每代迁移数的间接估计     

自然定居青冈幼苗的亲本分析

采用遗传排除法和似然分析法进行青冈幼苗亲本分析。共采用了５个等位酶多态位点,累积排除概率为７１．５７％。采用遗传排除法仅能为１株幼苗确定唯一的亲本,其余幼苗均有多个亲本。似然分析揭示出各轩有１或２对亲本,分析表明由成体自交形成的幼苗占４１．１８％,与种群个体间酱的概率也较大,为１７．６５％。成体之间的繁殖成功率变化较大,有９个个体的繁殖成功率为０。个体２４的繁殖成功率最大,占总的３９．４％,种群外     

云南纵坑切梢小蠹四个地理种群同工酶比较研究

采用不连续聚丙烯酰胺凝胶电泳技术研究了纵坑切梢小蠹（Ｔｏｍ ｉｃｕｓ ｐｉｎｉｐｅｒｄａ Ｌ．）４ 个自然种群的９ 个同工酶基因座。４ 个种群均在Ｅｓ－ １、Ｅｓ－ ２、Ｅｓ－ ４、Ｍｄｈ－ １、Ｍｄｈ－ ２ 及ＡＡＴ－ １ 基因座上存在遗传多态现象。路南长湖、楚雄、蒙自３ 种群间的遗传距离为０．００３６～０．０１７３, 平均值为０．０１０５, 表明其遗传结构基本相似。丽江种群与上述３ 种群之间的遗传距离为０．１４２１～０．２０３５, 平均值为０．１７６５,表明丽江种群与上述三种群已有了遗传分化。丽江种群近交系数较大,近亲繁殖程度较高。种群遗传结构的差异可能与不同蠹害程度之间存在一定的内在联系。     

凉水国家自然保护区天然红松林遗传变异的RAPD分析

采用随机扩增多态ＤＮＡ（ｒａｎｄｏｍ ａｍｐｌｉｆｉｅｄ ｐｏｌｙｍｏｒｐｈｉｃＤＮＡ ＲＡＰＤ）技术,研究了凉水国家自然保护区天然红松林的遗传变异水平及其分布规律。１６个１０ｂｐ长度的随机引物在８个实验样地内７２个个体中共检测了９６个位点,其中５５个是多态位点。在种水平上,红松的多态位点比率为Ｐ＝５８．５１％;Ｎｅｉ’ｓ遗传变异指数为Ｈ＝０．２８６８;Ｓｈａｎｎｏｎ’ｓ指数为Ｉ＝０．３６５４,所     

天然红松林等位酶研究

利用红松种子的单倍体胚乳,采用水平切片淀粉凝胶电泳技术,对采自三个地区的天然红松林的材料进行了１０种酶系统的等位酶实验,共获得了１８个等位基因位点,对这１８个位点等位基因的统计分析表明：红松种群的多态位点百分数为Ｐ＝７７．７８％,等位基因平均数为Ａ＝２．０,预期杂合度为Ｈｅ＝０．１６４８。红松种群间遗传分化程度在松属于较低水平。在红松１８个等位基因位点的变异中,绝大部分变异９４．２％来自种群内部,     

洪水干扰对青冈群更新的影响

本文在安徽黄山选择位于溪谷,受洪水干扰程度不同的３个样地,调查青冈种群的更新特征,结论如下：１．从幼苗数量来看,受洪水影响最轻的样地３个最多,密度为０．５８２５株ｍ＾－２,洪水影响最严重的样地１数量最少,密度仅为０．１１５０株ｍ＾－１,从幼苗性质来看,样地１萌生苗比率最高,３个样地中,随着高度级别增加,萌生苗的比例也增加。２．萌生苗高度的分布接近于对称的低峰分面     

微生境下羊草两种生态型种群的遗传多样性及遗传分化——等位酶分析

采用水平淀粉凝胶电泳技术,应用等位酶分析方法测定了松嫩平原南部微生境条件下羊草灰绿色和黄绿色两种生态型９个种群的遗传多样性和遗传分化程度。羊草种、种群和生态型水平都维持较高的遗传多样性。两种生态型之间有明显的遗传多样性差异及遗传分化。灰绿型和黄绿型的多态位点百分率分别为６７．３％和５７．１％,等位基因平均数分别是２．２和１．９,期望杂合度分别为０．３４８和０．２９８。两种生态型种群之间平均遗传距离     

古丈县南方红豆杉天然群体的遗传多样性研究

通过对分布于湖南省古丈县的南方红豆杉(Taxus chinensis)天然群体中30个个体的功能叶片的过氧化物酶(POD)和酯酶(EST)同工酶谱带的分析,研究了该天然群体的遗传多样性水平.结果表明:30个个体中都存在有迁移率相同的谱带(4条),占酶谱带总数的26.7%;两个酶系统共检出15条酶谱带,等位基因位点数4个,其中多态位点数3个,单态位点数1个,多态位点百分数P=75%,平均每个位点的等住基因数A=3,平均有效等位基因数Ae=2.75,平均期望杂合度He=60.7%,平均实际杂合度Ho=22.2%,表明该群体有较丰富的遗传多样性.     

EST‐SSR markers from the Pacific oyster,Crassostrea gigas

Ten polymorphic microsatellite repeat markers were identified from Crassostrea gigas, expressed sequence tags (EST) deposited in public sequence database. Number of alleles per locus ranged from three to 18, expected and observed heterozygosities ranged from 0.071 to 0.738 and from 0.306 to 0.913, respectively. Marker transferability was tested on other two Crassostrea species and polymorphic products were detected at nine loci. EST‐derived simple sequence repeats provide robust, informative and potentially transferable polymorphic markers suitable for population genetic, parentage, and mapping studies of C. gigas.     

Allozyme Variability and Phylogenetic Relationships in Honey Bee (Hymenoptera: Apidae: Apis mellifera) Populations From Greece and Cyprus

Ten gene enzymic systems (alpha-GPDH, AO, MDH, ADH, LAP, SOD, ALP, ACPH, ME, and EST), corresponding to 12 genetic loci, were assayed from five Greek populations representing three subspecies of Apis mellifera, A. m. cecropia (Pthiotida, Kythira), A. m. macedonica (Macedonia), and the "Aegean race" of A. mellifera, which is supposed to be very similar to A. m. adami (Ikaria, Kasos), as well as a population from Cypus (A. m. cypria). ADH( *)-1, ADH( *)-2, and LAP( *) electrophoretic patterns discriminate the Cyprus population from the Greek populations. MDH( *)-1, EST( *)-3, SOD( *), ALP( *), and ME( *) loci were found to be polymorphic in almost all populations. The observed heterozygosity was found to range from 0.066 to 0.251. Allele frequencies of all loci were used to estimate Nei's genetic distance, which was found to range between 0.011 and 0.413 among the populations studied. UPGMA and neighbor-joining phylogenetic trees obtained by genetic distance matrix methods, as well as a Wagner tree based on the discrete character parsimony method, support the hypothesis that the most distant population is that from Cyprus. Our allozymic data support A. m. cypria as a distinct subspecies, but there was no allozymic support for the distinction of the other subspecies existing in Greece.     

从公共数据库中利用数据挖掘的方法开发15条黄金鲈EST-SSR标记

黄金鲈是美国中西部地区重要的淡水经济型鱼类。TypeⅠ型标记对于比较作图和遗传学研究有相当重要的作用, 但是黄金鲈的TypeⅠ标记数量相当少。研究通过数据挖掘的方法从公共数据库中挖掘黄金鲈的TypeⅠ型即EST-SSR标记。实验结果分析了21968条EST序列, 约14.4%的序列包含不同类型的核心重复单元。CA重复是最丰富的二碱基重复单元。从中挑选62条包含SSR的EST序列设计引物, 筛选得到15对多态的微卫星位点。群体遗传学参数显示15对EST-SSR位点的等位基因数范围为4—19(平均数为9), 观测杂合度和期望杂合度的范围分别为0.103—0.929和0.116—0.934, 有4个位点偏离HWE平衡。研究得到的EST-SSR标记适用于黄金鲈的群体遗传学和基因组作图研究。     

Development of 28 EST‐SSR markers based on transcriptome sequences of Gobiobotia filifer and cross‐species amplification

Gobiobotia filifer is a small benthic fish distributed in Yangtze River Basin. The abundance of G. filifer increased after impoundment of Xiluodu Dam and Xiangjiaba Dam. The state of population structure and changes of genetic diversity before and after impoundment of Xiluodu Dam and Xiangjiaba Dam were interesting issues. However, efficient molecular markers were rare, which will limit us to solve above problems. Twenty‐eight expressed sequence tag SSRs (EST‐SSRs) were successfully identified and verified as stable amplification and polymorphic loci by polyacrylamide gel electrophoresis (PAGE) and capillary electrophoresis. The number of alleles at these EST‐SSR loci ranged from 3 to 14, the polymorphism information content values were 0.125–0.897, and the observed and expected heterozygosities were 0.0–0.857 and 0.132–0.928, respectively. Cross‐species amplification of the 28 loci developed in this study was examined in seven individuals of each of the 7 taxa. The amplification efficiency of 28 EST‐SSRs primer pairs is related to the distance of genetic relationship between cross‐species with G. filifer, and same subfamily species (Xenophysogobio boulengeri and Xenophysogobio nudicorpa) showed the highest (50%) amplification efficiency. These EST‐SSR markers could be used to analyse genetic diversity and population structure of G. filifer and related species.     

Utility of EST-derived SSRs as population genetics markers in a beetle

Microsatellite, or simple sequence repeat (SSR), loci can be identified by mining expressed sequence tag (EST) databases, and where these are available, marker development time and expense can be decreased considerably over conventional strategies of probing the entire genome. However, it is unclear whether they provide information on population structure similar to that generated by anonymous genomic SSRs. We performed comparative population genetic analyses between EST-derived SSRs (EST-SSRs) and anonymous SSRs developed from genomic DNA for the same set of populations of the insect Diabrotica virgifera, a beetle in the family Chrysomelidae. Compared with noncoding, nontranscribed regions, EST-SSRs were generally less polymorphic but had reduced occurrence of null alleles and greater cross-species amplification. Neutrality tests suggested the loci were not under positive selection. Across all populations and all loci, the genomic and EST-SSRs performed similarly in estimating genetic diversity, F(IS), F(ST), population assignment and exclusion tests, and detection of distinct populations. These findings, therefore, indicate that the EST-SSRs examined can be used with confidence in future genetic studies of Diabrotica populations and suggest that EST libraries can be added as a valuable source of markers for population genetics studies in insects and other animals.     

Development of new microsatellite loci for the genus <Emphasis Type="Italic">Polistes</Emphasis> from publicly available expressed sequence tag sequences

Over the last 20 years, microsatellites have revolutionized the study of cooperation in the social insects. The Polistes paper wasps have been an important model system for investigations of cooperative behavior. Recently, an expressed sequence tag (EST) library has been developed for P. metricus, allowing researchers to investigate the genetic basis of cooperative behavior in primitive social insect societies for the first time. We searched these freely available EST sequences for microsatellite motifs. This represents a relatively new approach to the development of microsatellite loci that allows for the development of a greater number of loci at less expense. We designed 32 PCR primer pairs, of which 23 amplified PCR products and 18 were polymorphic. These loci exhibited high levels of polymorphism, comparable to anonymous loci isolated via screens of partial genomic libraries. Thus, they are appropriate for population genetic studies as well as the reconstruction of colony genetic structure. A screen of the entire EST database found a total of 708 di-, tri-, tetra- and penta-nucleotide repeats with large repeat units typical of polymorphic loci and at least 30 bp of flanking sequence for primer design. This pool of potential loci represents a new genetic tool for P. metricus, as well as Polistes more generally, as there is great promise for cross amplification in other species.     

Development of EST‐SSRs in the Mediterranean blue mussel,Mytilus galloproviancialis

Eight polymorphic microsatellite repeat markers were identified from Mytilus galloproviancialis, expressed sequence tags (EST) deposited in public sequence database. Number of alleles per locus ranged from two to 10, and the observed and expected heterozygosities ranged from 0.029 to 0.872 and from 0.031 to 0.811, respectively. Three additional Mytiloida species assessed for cross‐species amplification revealed four loci could give positive amplifications. EST‐derived simple sequence repeats provide robust, informative and potentially transferable polymorphic markers suitable for population genetic, parentage, and mapping studies of M. galloproviancialis.     

Identification and genetic mapping of highly polymorphic microsatellite loci from an EST database of the septoria tritici blotch pathogen Mycosphaerella graminicola

A database of 30,137 EST sequences from Mycosphaerella graminicola, the septoria tritici blotch fungus of wheat, was scanned with a custom software pipeline for di- and trinucleotide units repeated tandemly six or more times. The bioinformatics analysis identified 109 putative SSR loci, and for 99 of them, flanking primers were developed successfully and tested for amplification and polymorphism by PCR on five field isolates of diverse origin, including the parents of the standard M. graminicola mapping population. Seventy-seven of the 99 primer pairs generated an easily scored banding pattern and 51 were polymorphic, with up to four alleles per locus, among the isolates tested. Among these 51 loci, 23 were polymorphic between the parents of the mapping population. Twenty-one of these as well as two previously published microsatellite loci were positioned on the existing genetic linkage map of M. graminicola on 13 of the 24 linkage groups. Most (66%) of the primer pairs also amplified bands in the closely related barley pathogen Septoria passerinii, but only six were polymorphic among four isolates tested. A subset of the primer pairs also revealed polymorphisms when tested with DNA from the related banana black leaf streak (Black Sigatoka) pathogen, M. fijiensis. The EST database provided an excellent source of new, highly polymorphic microsatellite markers that can be multiplexed for high-throughput genetic analyses of M. graminicola and related species.