基于AFLP技术的菜粉蝶遗传多样性初步分析

本研究选用陕西境内5个采样点采集的30个菜粉蝶个体,用AFLP技术分析了5个种群的遗传多样性。凝胶图经染色和分析发现总位点数为540个,其中504个为多态性位点,36个共有位点,具多态性的条带百分率为93.33%。结果表明:AFLP技术适合应用于菜粉蝶遗传多样性分析;荧光标记法在AFLP分析中具有较高的检测效率;南北坡5个地点种群的遗传多样性分化显示出山脉对菜粉蝶的隔绝作用。     

应用AFLP分析梅根系与其根围土壤丛枝菌根真菌DNA多态性差异

应用巢式PCR并进行梅根系与根围土壤丛枝菌根真菌（arbuscular mycorrihizal fungi,AMF）DNA扩增片段长度多态性（amplified fragment length polymorphism,AFLP）的差异比较,研究梅共生AMF的作用机理。结果表明,从18个梅品种的30个根围土壤样品中有28个样品获得纯化的DNA片段,占样品数93.3%,样品平均多态性位点数为6.5个,Nei’s基因多样性为0.3559±0.1382,Shannon信息指数为0.5299±0.1676。与梅根系AMF DNA多态性比较,根围土壤的平均多态性位点数明显较多;且根系AMF的DNA多态性位点绝大多数存在于土壤AMF的DNA多态性位点中,表明根系内AMF是由土壤AMF发育而来;根系与根围土壤AMF DNA的聚类均与梅品种群、品种关联性不强,表明AMF对宿主梅品种或品种群没有特异的共生关系。     

上饶早梨道地性农家种遗传多样性与亲缘关系的荧光AFLP分子标记分析

为了探讨上饶县花厅镇和田墩镇这两个相邻乡镇上饶早梨道地性农家种的遗传多样性与亲缘关系,采用6对Eco RⅠ/MseⅠ引物组合对其20个样本进行荧光AFLP分子标记分析。结果表明,上饶早梨2个道地性农家种20个样本6对引物组合扩增的平均位点数为84.83,平均多态性位点数为23.83,平均多态性百分率为28.09%。上饶早梨2个道地性农家种20个样本6对引物组合扩增位点的平均观测等位基因数Na为1.280 9,平均有效等位基因数Ne为1.207 6,平均Nie's基因多样度H为0.114 9,平均香农信息指数Ⅰ为0.166 1,遗传多样性水平较低。上饶早梨2个道地性农家种20个样品的遗传相似系数为0.748 5~1.000 0,平均值为0.890 6,个体间相似度较高。通过UPGMA聚类分析,上饶早梨2个道地性农家种20个样本被分为两大类。第Ⅰ类包括"花厅六月雪"和"花厅黄皮消",第Ⅱ类包括"田墩六月雪",表明上饶县花厅镇和田墩镇这两个相邻乡镇上饶早梨的道地性农家种("六月雪")虽然具有相似的遗传物质基础,但也存在明显的种植地差异。根据6对Eco RⅠ/MseⅠ引物组合扩增位点的特异性,并依据其扩增模式图进行编码组合,构建了上饶早梨2个道地性农家种20个样本的DNA分子指纹图谱,可以用于上饶早梨各种植地农家种分子水平上的鉴定。     

不同分布区天麻的AFLP分析

从贵州、云南、四川、陕西和辽宁收集了27份天麻样品,从64对AFLP选择性引物组合中筛选出16对组合,对不同分布区天麻的遗传多样性进行分析。16对引物共产生548条大小在100～1500 bp的谱带,其中多态性带428条,多态性比率(PP)达78%,说明不同分布区的天麻中存在一定的遗传多样性,且AFLP可以有效地进行天麻遗传多样性的分析。遗传差异分析结果表明,27个样品的遗传距离在0.5930～0.0187,平均为0.2199,表明不同分布区天麻个体间存在一定的遗传差异。5个省份的样品中来自贵州的样品遗传差异相对较大,表明贵州蕴藏着相对丰富的基因资源,可以作为天麻遗传改良的重要种质资源。不同变型的AFLP分析结果显示,3种变型从分子上无明显差异,说明天麻种内的变型仅仅是表型上的变异,尚未在遗传上固定下来,对天麻几个变型的划分是否成立还有待进一步研究。     

云南地区恒河猴线粒体DNA控制区遗传多态性研究

目的从分子水平探讨云南地区恒河猴遗传多样性,为今后开展恒河猴遗传资源的保护及合理利用提供借鉴和背景资料。方法采用PCR直接测序法测定云南地区恒河猴96份样品的线粒体DNA控制区全序列,用Mege 4.0和DNA SP软件对变异位点数、简约信息位点数、单倍型、单倍型多样度、核苷酸多样度等遗传信息进行分析,基于邻接法（neighbor-joining,NJ）和最小进化法（minimum-evolution,ME）构建系统发生树。结果在96份样品中,共检测出了149个多态性位点,定义了46种单倍型,单倍型多样度（Hd）为0.968±0.007,核苷酸多样度（Pi）为0.020。结论云南地区恒河猴存在着较丰富的遗传多态性。     

栽培沉香遗传多样性的ISSR和AFLP分析比较

探讨2种分子标记技术在沉香属药用植物遗传多样性研究中的应用。用ISSR和AFLP分子标记分析了海南、云南、广东、广西等地17份沉香属植物的遗传多样性。14个ISSR引物、8对AFLP引物分别检测到119、919个位点,多态位点百分率分别为73.95%、86.94%。由于AFLP标记具有较高的多态性位点检测效率,AFLP标记分析的遗传多样性参数高于ISSR。虽然基于Nei’s遗传距离的聚类分析结果存在着一定的差异,但用Mantel检测对两种方法检测的遗传一致度进行相关性分析表明,它们之间存在着明显的相关性（r=0.7705,P=0.0003）。ISSR标记与AFLP标记均能应用于沉香属植物的遗传多样性研究。两种标记的研究结果均揭示出沉香属植物具有较高的遗传多样水平。     

中国石榴栽培群体遗传多样性的荧光AFLP分析

以中国山东、安徽、陕西、河南、云南和新疆6个栽培石榴群体的85个品种类型为试材,利用荧光标记AFLP对中国石榴群体遗传多样性进行了研究。结果表明：8对引物组合在种级水平扩增的多态性位点数范围从135～185个不等,平均为158.25个,多态位点百分比范围为62.5%～86.11%,平均为73.26%,说明中国石榴品种遗传多样性较为丰富;石榴品种种级水平遗传多样性大于群体水平,6个群体的遗传多样性依次为河南群体〉新疆群体〉陕西群体〉安徽群体〉山东群体〉云南群体,并且具有显著性差异;群体间的遗传分化系数GST为0.2018,说明石榴遗传变异主要存在群体内,群体间的遗传变异占总变异的20.18%,根据基因分化系数,测得的基因流Nm为1.9027,说明中国石榴群体间存在适当的基因交流;UPGMA聚类分析结果表明,同一群体的大部分品种都聚在一起,但同时存在部分基因交流。所有遗传参数表明,中国石榴栽培品种遗传多样性较为丰富,其中河南群体遗传多样性显著高于其他群体,在中国石榴品种选育中具有更为广阔的应用前景。     

利用AFLP分子标记探讨蜡梅种质资源的遗传多样性

利用AFLP分子标记技术,对中国蜡梅种质资源7个野生种群的遗传多样性进行了研究。利用筛选出的3对引物,共扩增出253条谱带,其中218条多态带,多态位点占86.17% ;种群间的基因分化系数为0.2906,说明蜡梅基因多样性主要存在于种群内;种群总的Nei s基因多样性指数为0.2933,Shannon信息多态性指数为0.4487,蜡梅总的遗传多样性水平较高。蜡梅不同种群遗传多样性水平差异较大,种群多态位点百分率在65.44% ～87.16%之间,Nei s基因多样性指数为0.1653 ～0.4012,Shannon信息多态性指数为0.3132 ～0.5603。神农架种群(SN)和保康种群(BK)的遗传多样性水平较高。用NTSYS2.01版软件对样品进行UPGMA聚类分析,结果7个种群并没有按地理距离进行聚类。最后提出要对各蜡梅野生群体采取相应的迁地和就地保护措施。     

翘嘴红鲌雌雄基因组差异及太湖野生群体遗传多样性现状的AFLP分析

为发展翘嘴红鲌Erythroculter ilishaeformis(Bleeker)性别控制育种和单性养殖技术, 利用AFLP技术对翘嘴红鲌太湖野生群体中雌、雄各20个个体的基因组进行了遗传多样性和雌雄差异分析。用筛选出的8对AFLP多态性引物在太湖野生群体基因组中共检测到319个位点, 其中多态性位点185个。通过对所有多态性位点在个体中的分布进行分析, 发现一个只在雄性个体中稳定存在、在雌性个体中缺失的差异位点。在人工雌核发育翘嘴红鲌群体只有雌性个体, 其基因组中也检测不到该差异位点的存在。这些结果表明翘嘴红鲌性别分化可能受到严格的遗传调控, 该差异位点是雄性特有的性别分子标记。翘嘴红鲌太湖野生群体目前的多态位点比率P=57.99%, 观测等位基因数N_a=1.5799±0.4943, 有效等位基因数N_e=1.3859±0.3971, Shannon’s信息指数I=0.3221±0.2987。这些统计分析结果与10年前对该群体的AFLP研究结果(P=51.21%, N_a=1.512±0.500,N_e=1.252±0.371,I=0.218±0.275)相比没有显著差别(P>0.05), 说明该群体目前还具有适度的遗传多样性。     

利用RAPD和ISSR分子标记分析怀地黄种质遗传多样性

用RAPD与ISSR技术对怀地黄的8个品种和2个脱毒品系进行了种质遗传多样性分析。分别从80条RAPD引物和44条ISSR引物中筛选出适合怀地黄种质分析的17条RAPD引物和10条ISSR引物,用于RAPD和ISSR分析。17条RAPD引物共扩增出177条带, 多态性位点数为109; 多态性位点比率为61.58%;平均多样性指数(I)为0.3135;每个位点的有效等位基因数（Ne）是1.3641; 10条ISSR引物共扩增出110条带. 多态性位点数为79; 多态性位点比率为71.58%;平均多样性指数(I)为0.3577;每个位点的有效等位基因数（Ne）是1.4037。 基于扩增条带数据库建立了各自的Jaccard遗传相关系数矩阵,构建了相似的分子树状图,将10个供试材料分为2类:一类群含组培85.5、大田85.5、组培9302、大田9302、金状元和金白6个材料;另一类群含北京1号、大红袍、地黄9104和野生地黄4个材料。两种分子标记的分析结果呈极显著正相关(r＝0.649)。结果表明,RAPD与ISSR标记适合于怀地黄种质遗传多样性分析,ISSR标记技术是一种多态性和重复性优于RAPD技术的实用技术。     

Genetic structure among Thai populations of Aedes aegypti mosquitoes

Thirty‐one field populations of Aedes aegypti (L.) were compared using isozyme starch gel electrophoresis to characterize genetic variation between populations. Ae. aegypti were collected from seven provinces in Thailand. Thirty‐one isozyme encoding loci, including 19 polymorphic loci, were characterized. Only small levels of genetic differentiation were observed among the 31 district populations in the seven provinces. Isolation by distance among populations from the seven provinces showed no correlation between genetic variation and geographical distance.     

RAPD和ISSR标记对水稻化感种质资源遗传多态性的分析

运用RAPD和ISSR技术分析水稻化感种质资源的遗传多态性。从供试材料中筛选到具有多态性的RAPD引物12条,ISSR引物7条。RAPD引物共扩增到85条清晰的多态性条带,多态性条带比率为69．4％。ISSR引物共扩增到34条清晰的多态性条带,多态性条带比率为53．0％。对两种标记结果进行UPGMA聚类分析,结果极其类似,呈极显著的正相关(r=0．74)。聚类结果表明,地理位置相近的品种聚为一类。部分具有较强化感作用潜力的水稻品种亲缘关系很近,表明控制其化感作用性状的基因可能是等位的相同基因。而部分化感作用潜力差异显著的水稻品种聚为一类,这是由于人类在长期高产品种的定向选择过程中,水稻化感作用性状不被注意而丢失,遗传基础日益狭窄的原因。     

Estimation of genetic distance based on RAPDs between 11 cotton accessions varying in heat tolerance

The genetic distance of 11 cotton genotypes varying in heat tolerance was studied using RAPD markers. Fifty-three random decamer primers were used for the estimation of genetic distance. Among the 53 RAPD primers, which were custom synthesized by GeneLink Inc., UK, 32 were polymorphic and 21 were monomorphic. The 32 polymorphic primers produced 273 fragments, with a mean of 8.3 fragments per primer. The number of polymorphic bands produced in the 11 cotton accessions ranged from 1 to 31. Primer GLC-20 produced 31 polymorphic bands, while two primers, GLB-5 and GLC-12, produced one polymorphic band each. A range of 88.89 to 42.48% genetic similarity was observed among the 11 cotton accessions. The highest genetic similarity was observed between FH-945 and BH-160 (88.89%), whereas the lowest value was found between NIAB-801/2 and FH-945 (42.48%). Unique amplification profiles were produced by most of the cultivars; the differences were sufficient to distinguish them from other genotypes. This confirms the efficacy of RAPD markers for the identification of plant genotypes. An accumulative analysis of amplified products generated by RAPDs was sufficient to assess the genetic diversity among the genotypes. This information should be helpful for formulating breeding and genome mapping programs.     

野生垂穗披碱草种质的醇溶蛋白遗传多样性分析

用酸性聚丙烯酰胺凝胶电泳(A-PAGE) 对采集自中国新疆、青海、四川、西藏四省区的33份垂穗披碱草Elymus nutans材料进行醇溶蛋白分析,获得下述结果:（1）供试材料共分离出38条带纹,多态率达92.10%。4个电泳分区（α、β、γ、ω）的平均Shannon指数为0.55,Nei-Li遗传相似系数（GS）变异范围为0.36~0.93,平均值为0.63。这些结果说明供试野生垂穗披碱草材料具有较为丰富的醇溶蛋白遗传多样性。（2）对所有材料的聚类分析和主成分分析发现,在GS值为0.67的水平上供试材料可聚成7个类群,绝大部分来自于相同或相似生态地理环境的材料聚成一类,即醇溶蛋白图谱类型与材料的生态地理环境具有一定的相关性。（3）基于Shannon 多样性指数估算了5个垂穗披碱草地理类群内和类群间的遗传分化,发现类群内遗传变异占总变异的42.94 %,而类群间的遗传变异占总变异的57.06 %。这可能与该草以自花传粉为主的繁育系统有关。（4）对各地理类群基于Nei氏无偏估计的遗传一致度的聚类分析表明,各地理类群间的遗传分化与其所处的地理生态环境具有较高的相关性。 .     

Start codon targeted polymorphism for evaluation of functional genetic variation and relationships in cultivated peanut (<Emphasis Type="Italic">Arachis</Emphasis><Emphasis Type="Italic">hypogaea</Emphasis> L.) genotypes

Cultivated peanut possesses an extremely narrow genetic basis. Polymorphism is considerably difficult to identify with the use of conventional biochemical and molecular tools. For the purpose of obtaining considerable DNA polymorphisms and fingerprinting cultivated peanut genotypes in a convenient manner, start codon targeted polymorphism technique was used to study genetic diversity and relatedness among 20 accessions of four major botanical varieties of peanut. Of 36 primers screened, 18 primers could produce unambiguous and reproducible bands. All 18 primers generated a total of 157 fragments, with a mean of 8.72 ranging from 4 to 17 per primer. Of 157 bands, 60 (38.22%) were polymorphic. One to seven polymorphic bands were amplified per primer, with 3.33 polymorphic bands on average. Polymorphism per primer ranged from 14.29 to 66.67%, with an average of 36.76%. The results revealed that not all accessions of the same variety were grouped together and high genetic similarity was detected among the tested genotypes based on cluster analysis and genetic distance analysis, respectively. Further, accession-specific markers were observed in several accessions. All these results demonstrated the following: (1) start codon targeted polymorphism technique can be utilized to identify DNA polymorphisms and fingerprint cultivars in domesticated peanut, and (2) it possesses considerable potential for studying genetic diversity and relationships among peanut accessions.     

Genetic Relationships among Tall Coconut Palm (Cocos nucifera L.) Accessions of the International Coconut Genebank for Latin America and the Caribbean (ICG-LAC), Evaluated Using Microsatellite Markers (SSRs)

The diversity and genetic relationships among two accessions of tall coconut palms collected in Brazil and seven accessions introduced from different geographic regions of the world were analyzed using 25 microsatellite primers, 19 of which were polymorphic and detected between 4 and 10 alleles per locus, with an average of 6.57. The observed and expected heterozygosity ranged from 0.25 and 0.40 in the Rennell Islands Tall (RIT) accession to 0.54 and 0.62 in the Polynesian Tall (PYT) accession. The analysis of genetic structure resulted in the formation of five distinct groups. The first group was formed by the accessions Brazilian Tall—Praia do Forte (BRTPF), Brazilian Tall—Merepe (BRTMe) and West African Tall (WAT); the second group consisted of Malaysian Tall (MLT); the third group of RIT; the fourth group of Vanuatu Tall (VTT); and the fifth group of Rotuman Tall (RTMT), Tonga Tall (TONT) and PYT. The dendrogram based on the nearest-neighbor method detected the formation of two main groups and five subgroups, indicating that the genetic relationships of the accessions are based on their geographic regions of origin. The analyses revealed genetic relationships between the accessions collected in Brazil and the accession from Africa, and among palms from South East Asia and the South Pacific, confirming the common origin of these accessions. The information obtained in this study can guide decisions on germplasm conservation activities and the efficient selection of genetically divergent parents for use in coconut breeding programs in Brazil, which are attempting to select for disease resistance, mainly to lethal yellowing, among other characteristics.     

Genetic variability and population structure in Sapindus emarginatus Vahl from India

Sapindus emarginatus is an economically important tropical tree species sparsely distributed in different geographical provinces like Gangetic Plains, Western Ghats, and Deccan Plateau in India. In the present paper estimation of genetic variability within and among 41 accessions representing five populations was carried out using 3 single primer amplification reaction (SPAR) methods viz. RAPD, DAMD and ISSR. The cumulative data analysis was carried out for all three SPAR methods, and showed 82.32% polymorphism across all the accessions of S. emarginatus. Jaccard's similarity values among 41 accessions ranged from 0.15 to 0.49 with an average value of 0.37. The intra-population genetic diversity revealed highest values of Nei's genetic diversity (0.19,) Shannon information index (0.29) and polymorphic loci (55.18%), among the accessions of Gujarat (GJ) population, while the corresponding lowest values were (0.10), (0.15) and (26.40%) respectively among the accessions of Rajasthan (RJ) population. The maximum inter-population average genetic distance (0.20) was between Karnataka (KA) and RJ, while the corresponding least genetic distance (0.06) was between Allahabad (AL) and Varanasi (VS) populations. The analysis of molecular variance (AMOVA) revealed maximum percentage of variation among individuals of populations (72%) followed by 16% among regions and 12% among populations. Principal coordinate analysis (PCA) of cumulative data also supported the clustering pattern in the UPGMA dendrogram. These results suggest that genetic diversity is corroborating with the geographical diversity. Mantel's test was performed which revealed a highly significant correlation between cumulative vs RAPD, and showed the maximum (0.93) correlation coefficient, followed by cumulative vs ISSR (0.78) and cumulative vs DAMD (0.91) respectively, and this clearly indicates that the SPAR methods (RAPD, DAMD and ISSR) are sufficiently informative and are suitable to analyze the genetic variability within and among the populations of S. emarginatus.     

濒危植物翅果油树种群的遗传多样性和遗传分化研究

利用微卫星（SSR）标记对来自山西和陕西两省的7个翅果油树（Elaeagnus mollisDiels）种群进行遗传多样性和遗传结构研究。10对SSR标记共检测到126个位点,其中多态位点114个。在物种水平上,平均多态位点百分率为90.79%,有效等位基因数（Ne）、Nei基因多样性指数（H）和Shannon多样性指数（I）分别为1.6072、0.3166、0.4603;在种群水平上,多态位点百分率为61.99%,有效等位基因数（Ne）、Nei’s基因多样性指数（H）、Shannon多样性指数（I）分别为1.5445、0.2683、0.3815。遗传分化系数GST为0.2074,表明了翅果油树种群的遗传变异主要存在于种群内。基因流Nm为1.9111〉1,说明种群间基因交流可以阻止由于遗传漂变导致的遗传分化。聚类结果表明,翅果油树种群间的遗传距离与地理距离有一定的相关性,经Mantel检验,种群的地理距离与遗传距离之间呈正相关,但未达到显著水平（p〉0.05）。结果表明,遗传多样性水平与物种本身特性和不同干扰生境有关,濒危植物并不一定表现为遗传变异水平的降低。     

萝卜种质资源亲缘关系的RAPD分析

利用筛选出的12个随机引物,对来源于不同国家和地区的有代表性的56份萝卜种质资源遗传多样性进行了RAPD分析,共扩增出109条带,其中多态性带为72条,多态性带百分率为62.9%,种质平均期望杂合度为0.289.系统聚类分析将供试材料分为2大类、9组,主坐标分析将其分为3大类、7组,两种分类方法结果基本一致,后者能更为直观和清楚地反映群体之间的关系.     

38份瓠瓜种质资源遗传多样性的ISSR分析

采用ISSR分子标记技术对源自中国7个省份的38份瓠瓜种质进行遗传多样性分析。12个ISSR引物共扩增出96条多态性带,平均每个引物扩增的多态性带数为8条,多态性比率平均为83.5%。聚类分析将供试的38份种质分为4个类群8组,主坐标分析将其分为4个类群10组。ISSR分子标记的分类结果与瓠瓜的农艺性状分类和地理分布有一定的相关性。