EST-SSR和RAPD标记检测油菜(Brassica napus)遗传多样性

亲本选配是杂种优势利用中强优势组合配制的关键环节,遗传距离决定优势强弱。本文采用EST-SSR和RAPD两种分子标记技术检测甘蓝型油菜4份不育系、3份保持系1、0份恢复系和11份常规品种共35个材料的遗传多样性及与杂种优势的关系。结果共检测到399个等位位点,其中130个等位变异,占总检测位点的32.57%。NTSYS软件聚类分析结果表明:35份材料遗传距离范围为0.0280~0.2801,在遗传距离(GD)0.1401下分为6类,3个不育系Ogu、Polima和陕2A聚在第V类,Xin1 CMS(新1号不育系)遗传距离较远;不育系之间的遗传差异比不育系与保持系、恢复系及常规品种之间小,基本反映了品种(系)的遗传基础和系谱来源。     

EST-SSR分析不同产地丹参的遗传多样性

对来源于陕西商洛、河南内乡、四川中江、山东泰安4个产地共80个丹参株系种质资源进行EST-SSR分析,旨在探讨栽培丹参资源的多样性水平和产地间的遗传分化程度。结果表明,栽培丹参Nei基因多样度为0.2245,揭示出具有丰富的遗传多样性,且各产地丹参遗传分化程度低,遗传变异主要存在于产地内部;4个产地相比较,四川产地明显较低。UPGMA聚类分析结果表明,山东产丹参是相对独立的群体,但4个产地来源丹参的遗传距离与地理距离相关性未达到显著水平。栽培丹参具有较高的多样性以及产地间遗传分化程度较低,其异花授粉习性和产地内采用种子有性繁殖方式以及稍加人为选择的生产方法可能是其栽培丹参多样性高和产地间分化低的主要原因。     

SSR和SRAP标记研究油菜杂交种骨干亲本的遗传多样性

用SSR和SRAP两种分子标记方法研究51份甘蓝型油菜杂交种亲本系的遗传多样性,并对两种分子标记研究结果进行比较。结果发现,在51份材料中,45对SSR引物共扩增出194条多态性条带,平均每对引物为4.3条,25对SRAP引物共扩增出197条多态性条带,平均每对引物为7.9条。UPGMA聚类分析表明,SSR和SRAP标记都可将51份亲本材料划分为五大类群,本所选育的玻里马细胞质雄性不育系（Polima CMS）的主要保持系和恢复系都聚在同一类群的不同亚群中。根据系谱资料分析发现,SRAP标记划分的类群与系谱资料更为接近,SRAP标记更适用于遗传关系较近材料的遗传多样性分析。SRAP标记揭示的亲本间遗传距离要大于SSR标记揭示的遗传距离。两种不同标记方法揭示出油菜亲本遗传多样性的差异主要是由不同的标记方法揭示的标记位点等位基因变异数不同造成的。     

中国96个荔枝种质资源的EST-SSR遗传多样性分析

根据本实验室已获得的荔枝果皮cDNA文库EST序列,通过SSRIT在线检索,从3391条EST序列中,发现305条含有SSR,占整个文库EST的8.99%。利用SSR-ESTs序列共设计100对EST-SSR引物,其中62对在荔枝上有扩增产物,50对有扩增多态性,即具有一定的通用性。接着从96份荔枝种质中选取12个品种的基因组DNA,开展核心引物筛选,共筛选出多态性较好的EST-SSR分子标记30个;这30个EST-SSR分子标记在96份资源共扩出284条带,不同引物的扩增条带在3～18条之间,平均9.47条,其中有282条为多态性带,多态率高达99.30%,每对引物的Nei＇s基因多样度范围为0.186～0.396,香农信息指数范围为0.318～0.558;此外,系统聚类分析结果表明,在相似系数0.5525处,可将96份荔枝种质资源分成了8大类群,该8大类群基本与其生态类型和植物学性状特征相符。在此基础上,还对荔枝的主栽品种和特殊种质进行鉴别,结果表明,该30个EST-SSR分子标记在不同品种间可产生较清晰可辨的多态性差异,为荔枝品种以及种质资源鉴别和鉴定的分子指纹的构建奠定了良好基础。     

EST-SSR分析云南茶树资源的遗传多样性和亲缘关系

利用EST-SSR标记对云南134份茶树资源遗传多样性和亲缘关系进行了分析。30对引物共检测到等位位点127个,平均每对引物产生423个;共检测到263个基因型,平均每对引物所扩增的基因型有88个;遗传多态性信息含量平均达0501,高于其它地区的相关研究结果,表明云南茶树资源具有丰富的遗传多样性。资源间的平均遗传距离和相似系数分别为0413和0597,说明资源间的遗传差异比较大,遗传基础较宽。聚类可将134份资源划分为4大组。8个种群间的遗传相似系数变异范围为0753～0981,平均遗传相似系数为0891,表明不同种群间的遗传差异比较小。云南茶树资源间亲缘关系的揭示为今后茶树资源保存和新品种选育提供了一定理论依据。     

我国甘蔗亲本遗传多样性的AFLP标记分析

采用15对多态性较好的AFLP引物对我国自育的78个甘蔗亲本材料遗传多样性进行分析,结果表明,每对引物的多态性位点平均为65．67,多态陆位点率为82．55％。78个甘蔗亲本的遗传相似系数在0．4535～0．8927之间,平均为0．6821。相同组合后代的遗传相似系数较高,平均为0．7656。以遗传相似系数阈值约为0．700划分,聚类分析把78个亲本分为7大类,系谱记录中亲缘关系密切的亲本品系,大多数都能归为同一类。遗传多样性指数分析显示,不同年代亲本多样性指数差异明显,20世纪80年代最高,为0-3185,70年代最低,为0．2645;不同省区的亲本遗传多样指数变化更显著,在0．1952～0．2999之间,广东最高,云南最低。     

东南亚62个籼型水稻亲本SSR遗传多样性分析

为探讨东南亚水稻亲本间的遗传多样性,以东南亚62份籼型水稻亲本为材料,选择29对水稻功能基因标记以及平均分布于12条染色体、多态性较高和条带清晰的72对SSR引物进行遗传多样性和聚类分析。结果表明,32对多态性引物在62份水稻材料中检测到201个等位基因,每个位点等位基因数(Na)变异范围为2~12,平均为6.281;有效等位基因数(Ne)变异范围为1.067~5.399,平均为2.867;多态信息含量(PIC)变异范围为0.061~0.789,平均为0.515;平均Shannon信息指数(I)为1.176,变幅为0.143~1.908;观察杂合度(Ho)为0.977,范围为0.936~1.000;期望杂合度(He)为0.439,范围为0.179~0.937;固定指数(Fis)的范围为0.882~1.000;基因流(Nm)的范围为0~0.0157。聚类分析表明,在遗传相似系数为0.805处,东南亚水稻亲本被分为6大类,同一国家大多数品种聚为一类。相对于普通分子标记,功能基因标记的平均等位基因数不高,其遗传多样性参数也低于普通分子标记,东南亚各国水稻品种间的亲缘关系较近,遗传多样性程度较低。研究结果为水稻育种亲本选配、新种质资源的创制以及杂种优势利用等提供了科学依据。     

磨芋属（Amorphophallus）RAPD标记遗传多样性研究初报

本研究利用随机扩增多态性DNA（RAPD）技术对磨芋（魔芋）属内野生种和栽培种共20份材料进行基因组DNA多态性分析，用34个随机引物扩增，有23个扩增出的产物电泳图谱较清晰，共获得266个位点（DNA片段），其中259个具有多态性。供试材料所用23个的的扩增产物都存在种间多态性。7个引物扩增出的产物中有11条DNA片段在花磨芋种内样品（系统）间也存在多态性。以RAPD标记资料计算获得的传相似系数（Jaccard相似系数，Sj）进行UPGMA聚类分析，结果表明：花磨芋种内系统间差异最小，Sj系数在0.97-1.00间；两份甜磨芋材料间没有差异，Sj为1.00。在已知的种间，两个栽培种花磨芋和甜魔芋间亲缘关系最近，Sj在0.83-0.85间，与另一个栽培种白魔芋间亲缘关系都较远，Sj在0.62-0.66间，栽培种与野生种间亲缘关系都较远，Sj在0.48-0.64间。在野生种中，结节磨芋与栽培种系统间关系最远，Sj在0.48-0.54间，未定名4个野生种Sj在0.64-0.89间，系统A.sp05与A.sp06关系最近，Sj为0.89，其次是A.sp01与A.sp^*,Sj为0.73。根据亲缘关系树状图，当遗传相似系数Sj在0.55-0.60之间时，20份材料刚好划分为栽培种与野生种两个类群。     

油菜种子油酸含量的遗传改良

油菜是我国重要油料作物,菜籽油是我国城乡居民消费的主要食用油之一。菜籽油中的油酸营养价值很高,同时油酸也是一种重要工业原料。本文从国内外高油酸油菜育种现状、油菜籽油酸含量的诱变改良、遗传调控以及分子标记鉴定和QTL定位等几个方面介绍了油菜种子油酸含量遗传改良研究进展,旨在为今后进一步开展油菜高油酸育种研究提供参考。     

用RAPDs研究大豆根瘤菌的遗传多样性

采用ＲＡＰＤｓ分子标记研究２８株中国大豆根瘤菌的遗传多样性，１２个随机引物扩增产物电濂昆计算机聚类分析，得出反映菌株基因组序列相似水平的树状图。由树状图得知：ＲＡＰＤｓ分析结果可以准确地将供试大豆根瘤菌分为快、慢两群。每群中又可以再划分为两个亚群。本研究的结果还表明来源于新疆的一群快生型大豆根瘤菌显著不同于其它地区的快生型大豆根瘤菌菌株，是独立的一群，与陈文新等用表型性状的研究方法得出的结论一致。     

Analysis of Genetic Diversity in the Brassica napus L. Gene Pool Using SSR Markers

Genetic diversity throughout the rapeseed (Brassica napus ssp. napus) primary gene pool was examined by obtaining detailed molecular genetic information at simple sequence repeat (SSR) loci for a broad range of winter and spring oilseed, fodder and leaf rape gene bank accessions. The plant material investigated was selected from a preliminary B. napus core collection developed from European gene bank material, and was intended to cover as broadly as possible the diversity present in the species, excluding swedes (B. napus ssp. napobrassica (L.) Hanelt). A set of 96 genotypes was characterised using publicly available mapped SSR markers spread over the B. napus genome. Allelic information from 30 SSR primer combinations amplifying 220 alleles at 51 polymorphic loci provided unique genetic fingerprints for all genotypes. UPGMA clustering enabled identification of four general groups with increasing genetic diversity as follows (1) spring oilseed and fodder; (2) winter oilseed; (3) winter fodder; (4) vegetable genotypes. The most extreme allelic variation was observed in a spring kale from the United Kingdom and a Japanese spring vegetable genotype, and two winter rape accessions from Korea and Japan, respectively. Unexpectedly the next most distinct genotypes were two old winter oilseed varieties from Germany and Ukraine, respectively. A number of other accessions were also found to be genetically distinct from the other material of the same type. The molecular genetic information gained enables the identification of untapped genetic variability for rapeseed breeding and is potentially interesting with respect to increasing heterosis in oilseed rape hybrids.     

EST-SSR标记对我国斑点叉尾(鲴)种质资源的研究

采用EST-SSRs对福建和湖北的1984年群体(P1984)、福建与辽宁的1997年群体(P1997)、湖南的2004年群体(P2004)和福建的1984年与1997年群体杂交的F.代群体(P8497)等4个斑点叉尾鲴(Ictalurus punctatus)养殖群体的遗传多样性进行了研究.结果表明,有10对引物可扩增出清晰条带,其中9对引物具有多态性,共获得32个等位基因,4个群体的平均等位基因数(A)为3.00～3.40,平均有效等位基因数(Ae)为1.95～2.30,平均观察杂合度(Ho)为0.4768～0.5982,平均期望杂合度(He)为0.4913～0.5695,平均多态信息含量(PIC)为0.4113～0.4829,群体间的多态性差异不显著,且各群体的遗传多样性处于中等水平.根据群体间遗传相似性系数、遗传距离及UPGMA聚类分析发现,P1997和P2004群体之间的遗传距离最近,P1984和P2004群体之间的遗传距离最远.4个群体有18.75%的位点偏离了Hardy-Weinberg平衡,表明群体各位点的基因频率和基因型频率稳定性较好.F-统计检验发现,P2004和P8497处于不同程度的杂合子过剩状态,P1984和P1997处于杂合子缺失状态.群体间分化程度很弱,遗传变异主要来自群体内个体之间.     

白菜类蔬菜遗传多样性的AFLP分子标记研究

首次对白菜（Brassica rapa)类蔬菜的遗传多样性和分类进行了AFLP分子标记研究。共采用了137份材料，从64对引物组合中选择了4对扩增条带多，多态检出率高的3＋3引物组合，检测了210个位点，并对AFLP数据进行了聚类分析，结果表明，芜菁和白菜类蔬菜各自单独聚为一类，它们的亲缘关系较远。在白菜类蔬菜当中，所有大白菜和薹菜聚为一类，它们是比较特殊的类群，且亲缘关系密切，小白菜的聚类结果与其园艺学分类差别较大。小白菜各类型间的相似性程度较低，说明小白菜的起源较大白菜要早。大白菜的聚类表明，大白菜现有品种的遗传多样性较为狭窄。     

具双价基因的甘蓝型油菜游离小孢子的遗传转化

以双低(低芥酶和低硫甙)甘蓝型油菜(Brassica napus)游离小孢子为受体，通过根癌农杆菌(Agrobacterium tumefaciens)介导，将几丁质酶基因和β-1，3-葡聚糖酶基因导入杂交油菜新品种油杂4号亲本恢复系和保持系中，成功地获得了转基因植株。在小孢子数与根癌农杆菌数接近时，100-200mg／L羧苄青霉素能有效地抑制菌的生长，而不影响小孢子胚胎形成。用预培养2d的小孢子与根癌农杆菌共培养10h后离心，重新悬浮小孢子于含上述浓度的羧苄青霉素的NLN培养基中培养，获得了16株抗卡那霉素的恢复系的单倍体植株。经PCR及PCR-Southern blot检测，有10株呈阳性，证明外源基因已整合到油菜基因组中。     

豫南茶区茶品质相关性状与EST-SSR标记的关联分析

种质资源研究是育种工作的基础,关联分析为植物数量性状的研究提供了有力手段.本研究利用67对EST-SSR标记,对115份茶树(Camellia sinensis资源进行茶品质相关性状与EST-SSR标记的关联分析.基因间的连锁不平衡是关联分析的基础,67对EST-SSR组成的共2 211对成对位点组合中,均存在一定程度的连锁不平衡,由群体结构分析发现,当群体数目K=4时,模型后验概率LnP(D)最大,该群体被分为4个亚群.将各个材料的Q值作为协变量,分别进行4种目标性状的变异与EST-SSR标记变异的回归分析.由结果得知,与水浸出物、茶多酚、氨基酸和咖啡碱关联的标记共19个,其中与水浸出物关联的标记有5个,TM066对其解释率最高,为13.32％;与茶多酚关联的标记有5个,TM092对其解释率最高,为13.68％;与氨基酸关联的标记有6个,TM083对其解释率最高,为7.6％;与咖啡碱关联的标记有3个,TM111对其解释率最高,为7.8％.其中TM066、TM092和TM074-2与水浸出物和茶多酚同时关联;TM086-1与茶多酚和氨基酸同时关联;TM088、TM111和TM124与氨基酸和咖啡碱同时关联.这些研究结果可进一步用于相关性状位点的深入研究,为茶树的早期鉴定和茶叶品质的改良等提供一定的理论参考.     

Extending the rapeseed genepool with resynthesized Brassica napus L. I: Genetic diversity

Resynthesized Brassica napus L. could be employed to increase the genetic variation in the narrow oilseed rape genepool and to establish a genetically distant genepool for hybrid breeding. One important criterion for selecting appropriate resynthesized lines is their genetic distance to adapted breeding material. In this study we estimated the genetic distances in a wide collection of 142 resynthesized lines and 57 winter and spring rapeseed cultivars from Europe, North America and Asia using RFLP marker data. The highest in-group genetic distance (0.36) was observed in 142 resynthesized lines compared to 0.21 in winter, 0.23 in summer, and 0.28 in Asian genotypes. The group of adapted breeding material clustered into three groups of winter-, spring-type, and Asian genotypes. Resynthesized lines did not form distinct subgroups in the cluster analysis, but large differences were revealed in the genetic distance of resynthesized lines to the adapted winter oilseed rape genepool. The highest distance to winter oilseed rape was found in resynthesized lines with parental lines from the Asian genepool as B. oleracea convar. botrytis var. alboglabra (Bail.) Sun or B. rapa ssp. chinensis (L.) Hanelt.     

Uptake of zinc by Brassica napus as affected by sulphur supply

Industrial crops provide a possibility for utilization of heavy metal polluted soils. Knowledge of the factors which affect metal uptake by crops is therefore essential in order to develop concepts for the management of such soils. In pot experiments the uptake of Zn by oilseed rape increased considerably with the Zn supply. The increase of Zn uptake was counteracted partly by S. This protective effect of S was, however, not related to Zn retention in the roots.     

Genetic Diversity of Traditional Chinese Mustard Crops Brassica juncea as Revealed by Phenotypic differences and RAPD Markers

This investigation was aimed at exploring the genetic diversity among nine typical accessions of Chinese mustard crops using random amplified polymorphic DNA (RAPD) markers and morphological comparison. Totally, 111 reproducible DNA bands were generated by 16 arbitrary primers, of which 91 bands were proved to be polymorphic. Based on pair-wise comparisons of the amplified bands, genetic similarities were obtained using Nei & Li's similarity coefficients and a dendrogram reflecting their relationships was made using the unweighted pair–group method with arithmetic averages (UPGMA). The result of cluster analysis indicated that the nine accessions were capable of being classified into two primary groups, one including accession 2 with expanded root (root mustard), accession 3 with entirely expanded whole stem (long-stem mustard), accession 6 with edible leaves (leaf mustard), accession 8 with edible seed stalk (seed stalk mustard) and another one including accession 4 with expanded basal stem (short-stem mustard), accession 5 with bulgy petiole (leafy bulgy mustard), and accession 9 with mustard-rich seed (seed mustard). Besides, accession 1 with expanded root (root mustard) and accession 7 with edible leaves and seed stalk (seed stalk mustard) were independent of other accessions in the dendrogram. Additionally, by cluster analysis based on highly reproducible RAPD markers, the accessions with similar edible parts of leaves or roots were not actually in the same phylogenetic groups. This implied that they were probably derived from different geographical origins with dissimilar genetic background and possessed higher genetic diversification. Furthermore, the results indicated that the traditional method for classifying Chinese mustard crops was not much reliable as it was largely dependent on phenotypic behaviors. Meanwhile, the phenotypic differences among individuals did not necessarily mean they must have sharp difference in genetic background as they met in the same group. Undoubtedly, these results aforementioned make this crop quite interesting to researchers for further investigating the molecular evolution of this special AABB group.     

Genetic Survey of Chinese and Swedish Oilseed Rape (Brassica napus L.) by Simple Sequence Repeats (SSRs)

Eleven Chinese and twelve Swedish rapeseed (Brassica napus) genotypes were analysed by PCR with 41 microsatellite primers, generating a total of 50 loci. For these 50 loci, the number of alleles ranged from 1 to 14, and the average number of alleles per loci was 2.7. As an example of simple sequence repeat (SSR) scoring in Metaphor agarose gel, a single marker could distinguish 14 different DNA profiles. Based on cluster analysis (UPGMA), the dendrogram clearly distinguished three clusters, a cluster with exclusively Swedish genotypes, and two clusters with Chinese genotypes. The genetic diversity within the Chinese genotypes was broad compared to the genetic diversity within the Swedish material. The genetic similarity within the Swedish breeding lines ranged from 69.5 to 95.6%, while that of Chinese genotypes ranged from 57.1 to 81.6%. The results in this report will permit to establish a set of microsatellite primers that can be used for selecting appropriate parents for Brassica napus hybrids and for monitoring hybridity level.