梨种质资源遗传多样性研究中的RAPD技术引物筛选

以梨属44个种和品种为试验材料,利用RAPD技术从50个随机引物中筛选出18个多态性引物,用于梨种质资源遗传多样性研究。结果表明：所选出的多态性引物每个引物扩增出的条带数在4—11之间,扩增出的DNA片段分子量大多在450bp—2000bp之间,共扩增出118个条带,其中样品间相同的条带数有11条,呈现多态性的条带107条,多态百分率达90.8%。     

利用AFLP分子标记鉴定苹果砧木

利用AFLP分子标记技术,对30个苹果砧木进行研究。从64对引物组合中筛选出3对多态性高、分辨能力强的引物用于扩增,共获得199条带,其中多态性带176条,多态性率为88．4％。扩增结果显示,3对引物组合在12个砧木中扩增出特征带,且每对引物组合均能将所有砧木鉴别开,表明AFLP技术用于苹果砧木鉴定的效率很高。通过聚类,对供试砧木的遗传关系进行分析,为中国优良苹果砧木资源的进一步收集和利用提供科学依据。     

应用AFLP技术检测水稻遗传多样性的研究

利用扩增片断长度多态性（Amplified fragment lenth polymorphism简作AFLP)分子标记技术研究了23个水稻品种的遗传多样性从49对AFLP引物中筛选出4对多态性高，分辨能力强的引物。4个AFLP引物组合分别扩增出43、37、49、33条多态性带，平均每个引物组合扩出40．5条多态性带，4个引物组合共扩增出246条带。利用AFLP数据进行聚类分析，将23个品种聚为10个类群，结果表明，AFLP在水稻类群划分的应用是可行的。     

AFLP在水稻类群划分研究中的应用

利用AFLP分子标记技术研究了22个水稻品种的遗传多样性，从49对AFLP引物中筛选出了4对多态性高，分辨能力强的引物，4个AFLP引物组合分别扩增出43、37、49、33条多态性带，平均每个引物组合扩出40．5条多态性带，4个引物组合共扩增出246条带。利用AFLP数据进行聚类分析，将22个品种聚为8群，结果表明，AFLP在水稻类群划分的应用是可行的。     

马铃薯种质遗传多样性分析的AFLP反应体系优化与引物筛选

本试验主要对AFLP反应体系进行优化,并用该体系筛选适用于马铃薯种质资源遗传多样性分析的引物。酶切连接、预扩增和选择性扩增体系的优化结果表明,建立的马铃薯AFLP反应体系为:模板DNA160ng,37℃酶切连接12h;预扩增体系中dNTP浓度为0.2mmol/L,TaqDNA聚合酶用量为1U;选择性扩增体系中预扩增产物稀释20倍,引物终浓度为2.5ng/μL。利用优化后的AFLP反应体系,以5个马铃薯品种为试材筛选选择性引物,可以从81对引物组合中选出16对条带丰富且多态性较高的引物组合。本研究为种质资源鉴定、马铃薯遗传多样性以及马铃薯抗病性研究等奠定了良好的基础。     

大白菜的适宜AFLP-Pst I/Mse I引物组合

基于PCR的DNA指纹鉴定技术AFLP广泛应用于生物多样性、遗传图谱构建、基因定位、分子系统发育和品种鉴定等方面.为了筛选出大白菜适宜的AFLP引物组合,研究以抗根肿病大白菜双单倍体CR Shinki、感病自交系94SK及其后代F2构成的纯合抗病和纯合感病DNA混合池为材料,利用256对Pst I/Mse I引物组合进行了AFLP分析.结果表明:平均每个组合检测到55条带,共扩增13 079条带,平均每1 000条带检测到1.30个根肿病抗性基因连锁标记;多态性带数为3 167条,双亲间多态性频率约为0.24;扩增带数与多态性带数呈线性正相关,引物组合中的不同GC含量与扩增带数和多态性带数存在显著性差异,并表现出线性负相关.筛选出的适宜53对引物组合共扩增出4 381条带,占总扩增片断的33.50%,平均每对扩增出83条,其中9个组合扩增出与抗根肿病基因连锁标记.     

羊耳蒜遗传多样性研究中AFLP反应体系的建立与初步应用

为研究羊耳蒜种质资源遗传多样性,建立并初步应用羊耳蒜AFLP反应体系。以羊耳蒜幼嫩叶片为材料,采用常规SDS法提取基因组DNA,通过优化AFLP反应体系中的几个关键因素,建立适合羊耳蒜的AFLP银染反应体系,并利用筛选出的引物组合对羊耳蒜的遗传多样性进行初步研究。经EcoRⅠ和MseⅠ酶组合37℃酶切3 h后可将500 ng基因组DNA完全切开;酶切产物和接头经16℃连接过夜后,用带有1个选择性碱基的预扩引物和带有3个选择性碱基的选扩引物分别进行扩增,扩增产物经变性聚丙烯酰胺凝胶电泳分离,银染,能够得到清晰的扩增图谱。3对引物组合对8个羊耳蒜种群共185个体的扩增共得到221条条带,其中多态性条带195条,多态性条带百分率为88.24%。本研究结果表明建立的AFLP反应体系可用于羊耳蒜种质资源遗传多样性研究。     

版纳甜龙竹DNA提取方法及AFLP反应体系建立研究

用改进的CTAB法,在提取液中加入2%PVP(V/V)和2%β-巯基乙醇,提取到了高质量的基因组DNA,OD260/OD280在1.7～1.9之间,蛋白质、多酚类、色素、RNA等去除较彻底,适于AFLP分析。通过对版纳甜龙竹DNA提取、酶切连接、预扩增、选择性扩增等试验过程中各关键因素的比较研究,建立了优化的AFLP分子标记体系,得到了清晰的AFLP银染指纹图谱,试验结果重复性好。从64对MseI和PstI引物中筛选出8对扩增效果好的引物,利用筛选出8对引物对30份材料进行分析,共扩增出256条多态性带,获得32490个扩增位点,有13289个位点具有多态性,平均每对引物获得4061.25个扩增位点,其中具有多态性的位点为1661.125个,平均多态检出率为40.90%,8对引物组合对版纳甜龙竹30个个体的区分率达到100%。表明AFLP用于版纳甜龙竹种内不同材料间的遗传变异性分析是可行的。     

独脚金AFLP反应体系的优化及引物筛选

为了构建一套适合中国独脚金种质资源的AFLP反应体系,本研究以独脚金幼嫩茎叶为材料,对影响AFLP反应体系的酶切连接反应、预扩增和选择性扩增过程中的一些关键因素进行优化,并利用优化的反应体系对AFLP引物进行筛选。结果表明,最佳的酶切反应体系为DNA模板200 ng,MseⅠ/EcoRⅠ用量3 U,总体积20μL,37℃酶切反应时间3 h,72℃灭活20 min;最佳连接反应体系为T4连接酶5 U,16℃连接过夜;最佳预扩增反应体系为dNTP浓度0.2 mmol/L,Taq DNA聚合酶浓度2 U,总体积25μL;选择性扩增的反应体系为d NTP浓度0.2 mmol/L,Taq DNA聚合酶浓度1 U,预扩增产物稀释5～10倍,总体积10μL。采用优化的AFLP反应体系,对来自3个不同来源地的独脚金样本进行选择性扩增,100对引物组合均能扩增出清晰、丰富的条带,且在参试样本中均能表现出一定的扩增多态性。本研究筛选出的引物组合可用于后续独脚金种质资源遗传多样性的研究,为独脚金遗传多样性研究、种质资源保存和鉴定提供一定的参考。     

AFLP分子标记在玉米优良自交系优势群划分中的应用

本文利用AFLP分子标记技术研究了17个玉米优良自交系的遗传多样性, 4个AFLP引物组合分别扩增出30、 30、 44、 41条多态性带, 平均每个引物组合扩出36.25条带, 4个引物组合共扩增出145条带, 每一个引物组合都可将17个自交系完全分开。 利用AFLP数据、 进行聚类分析, 将17个优良自交系聚为6群, 结果表明, 用AFLP标记进     

适合甜菜品种鉴定的SRAP核心引物的筛选

为筛选适合甜菜品种纯度鉴定的SRAP核心引物,以12个进口国外甜菜品种为材料,对546对SRAP引物组合进行扩增,利用8%的非变性聚丙烯酰胺凝胶电泳进行分离,选择适合甜菜品种纯度鉴定的SRAP核心引物组合。结果从546对SRAP引物组合中筛选出扩增条带清晰、多态性丰富、重复性好的引物组合23对,这23对引物组合共扩增出177条多态性条带,引物的PIC值均大于0.6。平均每对引物扩增7.7条多态性条带,从理论上讲,这些核心引物完全可以实现对现有甜菜品种的鉴定。     

甜菜SCoT核心引物的筛选

【研究目的】为了筛选出适合甜菜品种遗传多样性分析的SCoT引物,为SCoT引物得以在甜菜中进行深入应用奠定基础,本研究甜菜以8个来自不同国家的甜菜品种为材料对80条SCoT引物进行扩增【方法】扩增方法采用SCoT-PCR最优反应体系包含2.0 μL的10×PCR buffer（含Mg2+）、10 ng的DNA、0.5 U的Taq DNA聚合酶、10 μmol/L的引物2 μL以及0.1 μL的dNTPs (2.5 mmol/L each)。【结果】结果从80条SCoT引物中筛选出20条多态性高的引物,这20条引物最多扩增出16条多态性条带,最少扩增出2条多态性条带,扩增总条带155条,其中多态性条带为134条,多态性条带的百分比为86.5%。【结论】通过对核心引物的有效性验证,表明筛选出的20个核心引物非常适合用于甜菜指纹图谱的构建。     

Identification of polymorphic DNA markers in cultivated peanut (Arachis hypogaea L.)

The detection of DNA polymorphism in cultivated peanut (Arachis hypogaea L.) is reported here for the first time. The DNA amplification fingerprinting (DAF) and amplified fragment length polymorphism (AFLP) approaches were tested for their potential to detect genetic variation in peanut. The AFLP approach was more efficient as 43% of the primer combinations detected polymorphic DNA markers in contrast to 3% with the DAF approach. However, the number of polymorphic bands identified using primers selected in both approaches was comparable. In the DAF study, when 559 primers of varying types were screened, 17 (mostly 10-mer types) detected polymorphism producing an average of 3.7 polymorphic bands per primer with a total of 63 polymorphic markers. In the AFLP study, when 64 primer combinations (three selective nucleotides) corresponding to restriction enzymes Eco RI and Mse I were screened, 28 detected polymorphism. On an average, 6.7% of bands obtained from these 28 primer pairs were polymorphic resulting in a total of 111 AFLP markers. Our results demonstrate that both AFLP and DAF approaches can be employed to generate DNA markers in peanut and thus have potential in the marker-assisted genetic improvement and germplasm evaluation of this economically important crop. This revised version was published online in July 2006 with corrections to the Cover Date.     

Genetic variation within and between two cultivars of red clover (Trifolium pratense L.): Comparisons of morphological,isozyme, and RAPD markers

Summary Morphological, isozyme and random amplified polymorphic DNA (RAPD) markers were used to estimate genetic variation within and between cultivars of red clover (Trifolium pratense L.), an important temperate forage legume. Two cultivars of red clover, Essi from Europe and Ottawa from Canada, were evaluated. Six monogenic morphological characters were observed for 80 plants from each of these two cultivars. All six morphological loci were polymorphic in the cultivar Essi whereas only four loci were polymorphic in the cultivar Ottawa. Forty plants from each cultivar were assayed for isozyme markers. A total of 21 enzyme-coding loci with 43 alleles was detected using twelve enzyme systems. Thirteen and nine of these loci were polymorphic in Essi and Ottawa, respectively. The mean number of alleles per locus was 1.81 in Essi and 1.67 in Ottawa. Seventeen random 10-mer primers were screened for RAPD markers. Nine primers which gave clear and consistent amplified products were used to assay 20 individuals from each cultivar. Each primer gave from 7 to 20 amplified bands with an average of 14.8 bands per primer. One hundred and eight of 116 putative loci were polymorphic in Essi and 90 of 98 loci were polymorphic in Ottawa. High within-cultivar variation was observed in both cultivars using both isozyme and RAPD markers. This high polymorphism makes these markers useful for germplasm characterization and genetic studies in red clover.     

87份中熟棉种质资源亲缘关系和遗传多样性研究

为了阐明不同中熟棉种质资源间的亲缘关系,为优势杂交组合选配亲本材料,最终得到目标优良种质及审定品种,利用SRAP分子标记技术对87份中熟棉品种（系）进行遗传多样性分析。从80对引物组合中筛选出多态性引物,用于供试材料的PCR扩增。结果显示,筛选出的17对多态性引物共扩增出168个位点,其中90个位点呈现多态性,平均每对引物产生5.29个多态性位点,多态率达53.57%。利用NTSYS-pc2.11软件数据分析显示,87份材料之间的相似系数为0.61~1.00,平均值为0.82。当遗传相似系数为0.73时,可将87份棉花材料分为两大类,其中第Ⅰ类群包含65个材料,第Ⅱ类群包含22个材料。遗传多样性分析表明本文中选用的中熟棉种质资源遗传基础比较狭窄,今后结合分子标记结果选用亲缘关系较远的材料作为杂交亲本,创制新的中熟棉种质资源。     

河南栽培大豆的RAPD品种鉴定和聚类分析

用CTAB法提取了10个大豆品种总DNA,使用RAPD技术对其进行了品种鉴定和聚类分析。从73条随机引物中筛选出12条扩增出较稳定DNA条带的引物扩增这些品种总DNA,共扩增出67条带,大小0．2-5 kb,每种引物扩增出4-9条带;多态性条带共51条,多态性比例为76．12％。利用SPSS11．0软件所做的统计分析和聚类分析结果表明,10个品种间的相似系数在0．528-0．776之间,平均相似系数为0．641 6;可聚成3类:豫豆24号、周豆11号、周豆 12号、豫豆11号、周豆13号、豫豆6号,可聚为A类;中作98-3和豫豆15号可聚为B类;豫豆26号和豫豆22号聚为 C类。同一类品种间体现了一定的相关性。     

基于菜心(Brassica campestris)基因组Survey测序开发多态性SSR标记

为解决菜心SSR标记数量不足、已开发的位点多态性差等问题,本研究利用高通量测序技术,对‘四九-19’和‘3T6’两份菜心材料进行基因组Survey测序,规模化开发多态性SSR标记。两个菜心材料分别获得55 649 657个和59 300 433个Clean reads,分开拼接组装得到430 483个和499 876个Contig。在两个材料的Contig中搜索到共有的SSR位点为30 696个,其中以二和三核苷酸重复基序最为丰富,占总SSR位点的67%。分析比较发现,3 652个(12%) SSR位点在两份测序材料间具有潜在多态性,随机挑选50个SSR位点进行PCR扩增验证,48对(96%)引物在4份菜心材料中扩增出清晰的条带,其中31对(62%)引物在两份测序样品间具有多态性,19对(38%)引物在另两份菜心材料间具有多态性。结果表明,利用基因组Survey测序能开发SSR标记和开发具有多态性的SSR标记,本研究开发的多态SSR标记将进一步为菜心分子标记的发展和应用提供基础。     

142份甜高粱品种的分子身份证构建

从分布在高粱染色体10个连锁群上的103对SSR引物中,筛选出41对多态性引物, 并用其扩增国内外142份甜高粱种质资源, 检测到189个多态性片段, 每对引物的等位基因数在2~11之间,平均为4.6个。引物位点的多态信息含量指数(PIC)变幅为0.089~0.850,平均为0.543。品种间特异指数差异较大,介于109.1~454.7之间,平均为189.0。结果表明, 根据引物的等位基因数确定11对引物(Xtxp329、Xtxp258、Xtxp113、Xtxp303、Xtxp61、Xtxp201、Xtxp14、Xtxp91、Xtxp47、Xtxp217和Xtxp67)组合, 并用于构建142份品种资源的分子身份证, 有效地区分了各品种。     

Genetic analysis of a CSR10 (indica) × Taraori Basmati F3 population segregating for salt tolerance using ISSR markers

Segregation for salinity tolerance and ISSR markers based molecular polymorphism were investigated in a F₃ plant population raised via single-seed descent method from a cross between salt-tolerant indica rice variety CSR10 and salt-susceptible premium traditional Basmati rice variety Taraori Basmati HBC19. A total of 130 F₃plants were evaluated individually for salinity tolerance on 1–9 scale on the basis of seedling growth parameters; the average score ranged between 1.7 to 8.3. Frequency distribution curve obtained using the salinity tolerance data of F₃ population and a chi-square analysis, showed a good fit to a normal distribution. Eleven plants each in the category of salt-tolerant and salt-susceptible were selected from the segregating F₃ population for ISSR marker analysis. A total of 149 bands (4–11 bands per primer) ranging from 200 to 3530 bp were scored for the two rice varieties and the selected CSR10 × HBC19 segregating F₃ plants using 26 ISSR primers. Of these, 89 were monomorphic and 60 were polymorphic. Of the 60 polymorphic bands,36 and 20 bands were specific to CSR10 andHBC19 respectively. The remaining four bands were amplified using UBC primers 810,848, 853 and 886 and present in only some of the CSR10 × HBC19 F₃ plants. Notably, ISSR primers with dinucleotide repeat motif and 5'-anchored end amplified more number of bands (7.0 bands/primer) compared to3'-anchored dinucleotide primers (5.4bands/primer), but 3'-anchored dinucleotide primers revealed higher level of polymorphism (2.6 polymorphic bands/primer) compared to 5'-anchoreddinucleotide primers (1.43 polymorphic bands/ primer). While distribution of majority of the polymorphic bands were more or less in the expected ratios in salt-tolerant and/or salt-sensitive F₃segregating plants, but some of the bands amplified using UBC ISSR primers 823, 825,826, 849, 853, 864, 866 and 884 showed highly skewed distribution. Such polymorphic bands stand greater chances of having a linkage with the genes/ QTLs for salinity tolerance and shall be the target for further studies. This revised version was published online in July 2006 with corrections to the Cover Date.     

基于RAPD标记的芥蓝种质资源遗传多样性分析

调查了44份芥蓝种质的植物学性状,并利用RAPD分子标记分析了其遗传多样性。结果从150条随机引物中筛选出20个引物,20个引物共扩增出177条谱带,其中多态谱带105条,平均每个引物扩增出8.9条谱带和5.3条多态性谱,多态性比率为59.32%。基于RAPD标记,利用NTSYS-pc2.11构建了聚类树状图谱,遗传距离为0.70时,44份芥蓝资源可聚成六大类群。芥蓝种质存在着一定的遗传多样性,但原产华南而且主要产区也在华南,遗传多样性要小于芸薹属其他蔬菜。