Evaluation of Genetic Diversity in Chinese Wild Apple Species Along with Apple Cultivars Using SSR Markers

China, one of the primary centers of genetic diversity for the genus Malus, is very rich in wild apple germplasm. In this study, genetic diversity in 29 Malus accessions, including 12 accessions from 7 Chinese Malus species, 4 Chinese landraces, and 13 introduced apple cultivars, was assessed using a set of 19 single-locus simple sequence repeat (SSR) markers distributed across all 17 linkage groups of the apple genome. The number of alleles detected at each locus ranged from 2 to 11, with an average of 5.3 per SSR marker. In some accessions, 16 unique alleles were identified. Ten out of these 16 unique alleles (62.5%) were detected exclusively in wild species, indicating that these Chinese wild apple species have considerable genetic diversity and can be used in breeding programs to increase the genetic diversity of apple cultivars. Using 19 SSRs, an unweighted pair-group method with arithmetic average cluster analysis was conducted, and the resulting dendrogram revealed that all cultivars, except for E??peMeBckoe, were clustered together in the same group. The Russian cultivar E??peMeBckoe was closely related to the Chinese crabapple Baihaitang (M. prunifolia), with a high similarity coefficient value of 0.94. Of the two M. sieversii accessions used, one accession showed a close relationship to apple cultivars, while the other accession was closely related to wild apple species, suggesting the presence of a wider genetic diversity in Chinese M. sieversii species. The influence of SSR marker selection on genetic diversity analysis in this Malus collection was also discussed.     

福建省近年来审(认)定花生品种的遗传多样性分析

以近年来通过福建省审(认)定的23个花生品种为材料,对株型、叶形、叶片大小、叶色、荚果形状、网纹粗细、网纹深浅、开花习性、种仁大小、种皮颜色和粒形共11个表型性状的Simpson遗传多样性指数(简称SI)和Shannon-Weaver遗传多样性指数(简称H')进行了分析。结果表明:除开花习性、种皮颜色和种仁大小3个性状表现一致外,23个品种的遗传多样性指数分别为SI=0.506,H'=0.796,其中以荚果形状最低(SI=0.237,H'=0.387),以网纹粗细最高(SI=0.755,H'=1.335);从50对引物中筛选出9条多态性较好引物,共扩增出59条多态性条带,平均每对引物可扩增6.56条多态性条带,引物的多态性信息含量(PIC)变幅为0.746~0.957,平均值为0.88。23个品种间的遗传相似系数在0.225~0.818,平均为0.579。在相似系数0.55处可分为3个类群。系谱分析表明亲本来源相近的品种优先聚在一起,利用辐照诱变材料对于拓宽花生遗传基础发挥作用较明显。SSR分析结果基本上与系谱分析的结果相吻合。     

桂花品种资源的遗传多样性分析

根据桂花（Osmanthus fragrans）品种的形态特征,结合AFLP分子标记,对部分桂花栽培品种进行了遗传多样性分析。结果表明,桂花品种之间存在着较为丰富的遗传多样性,AFLP分子标记检测到的多态性条带占总扩增条带的57.46%。根据桂花品种的主要性状特征,利用数值分类法对其进行分类,并用UPGMA法对AFLP结果进行聚类分析,结果均显示桂林地区的桂花品种存在明显的区域性,花色可以作为重要的分类标准,同时对桂花品种的分类系统进行了探讨。     

桂花品种资源的遗传多样性分析

根据桂花(Osmanthus fragrans)品种的形态特征, 结合AFLP分子标记, 对部分桂花栽培品种进行了遗传多样性分析。结果表明, 桂花品种之间存在着较为丰富的遗传多样性, AFLP分子标记检测到的多态性条带占总扩增条带的57.46%。 根据桂花品种的主要性状特征, 利用数值分类法对其进行分类, 并用UPGMA法对AFLP结果进行聚类分析, 结果均显示桂林地区的桂花品种存在明显的区域性, 花色可以作为重要的分类标准, 同时对桂花品种的分类系统进行了探讨。     

河北省大豆推广品种遗传多样性分析

利用主要农艺性状以及SSR和AFLP2种分子标记,对河北省41个大豆推广品种进行遗传多样性分析,以便为种质资源利用和创新提供依据。农艺性状聚类结果将41个材料划分为3个类群和2个特殊品种,聚类结果与材料系谱来源相差悬殊,不能反映材料间亲缘关系。SSR和AFLP数据聚类结果将41个材料划分为4个SAG（SSR and AFLP—basedgroups）分子类群。30对SSR引物共检测出135个等位变异,平均每个位点上有4．47个等位变异,SSR的遗传多样性指数（Simpson）分布范围为0．0928～0．7800,平均值为0、6442。10对AFLP引物共扩增出93个多态性标记,平均每对引物9．3个多态性标记。品种间的遗传相似系数（GS）变化范围为0．5877～0．9868,平均值变化范围为0．6732～0．7653,总体平均值为0.7237,遗传相似系数较高,说明材料间遗传变异较小。     

基于苹果EST-SSR的梨种质资源遗传多样性分析

利用来自苹果的8对EST-SSR标记对48份梨(Pyrus)种质资源进行遗传多样性研究,以分析其在梨属植物上的通用性.结果表明,8对EST-SSR引物在供试材料上均能扩增出与苹果大小相似的产物,所有引物共检测到140个基因位点,其中多态性位点129个,多态性比例为92.14%,并且可成功区分不同品种.根据EST-SSR标记所揭示的多态性和UP-GMA法聚类分析,48份梨种质资源在相似系数0.62处可分为东方梨和西方梨两个种群,而中国的白梨(Pyrus bretschneideri Rehd.)、砂梨(P.pyrifolia Burm.f.Nakai)和秋子梨(P.ussuriensis Maxim.)相互交错在一起,没有独自成组.可见,苹果的EST-SSR标记在梨上具有高度的可转移性,可应用于梨属植物的资源评价及遗传关系研究.     

吉林省大豆育成品种的遗传多样性特点分析

利用SSR分子标记技术对吉林省近年来新育成的56份大豆品种进行遗传多样性分析,以来自其他14个省份的16份大豆育成品种为对照,结果表明,吉林省育成品种15个SSR位点的等位变异数和特异等位变异数(76,12)均低于省外品种(78,18)。吉林省育成品种的遗传多样性指数(0.63,1.23)均极显著低于省外品种(0.76,1.55)。聚类分析与主成分分析结果都表明,四川省、山西省和内蒙古自治区的育成品种与其他品种的遗传距离较远。通过对不同年份平均遗传相似系数的比较,明确大豆育成品种的遗传基础的发展趋势,表明吉林省育成品种的遗传基础与省外品种相比,遗传变异较少,遗传基础较狭窄,应不断引入外省遗传变异大且亲缘关系较远的品种以拓宽其遗传基础。     

亚麻遗传多样性的RAPD分析

从600个随机引物筛选出28个扩增稳定性较好的引物,对18份来自不同国家和地区的亚麻资源遗传多态性进行RAPD分析。结果表明：共扩增出条带529,其中多态性条带201,总的多态性百分率（PPB）为38．0%。用NTSYSpc（2．10）软件进行UPGMA聚类分析,18个亚麻品种遗传距离为0．0469～0．1332之间,可分3大类,其中红木5号与匈牙利5号亲缘关系最近,ABYSSINIA（BROWN）和匈牙利5号遗传距离相差最显著,达到0．1332。     

Virulence and Molecular Diversity of Venturia inaequalis in Commercial Apple Growing Regions in Kashmir

Seventy‐one isolates of Venturia inaequalis collected from commercial apple growing areas of Kashmir were characterized on international differential apple hosts and analyzed by Random Amplified Polymorphic Microsatellites (RAMS), PCR–RFLP and sequencing of rDNA for elucidation of variability. Virulence analysis on a differential set categorized them into four pathogenic races, viz. (0), (1), (2) and (1,2) in the first time comprehensive molecular analysis of this in India and especially from Jammu and Kashmir, a north‐western Himalayan state of India. Race groups (0), (1), (2) and (1,2) contained isolates from diverse areas without specificity to any geographical zone or region. Cluster analysis of the RAMS and PCR–RFLP revealed a high genotypic diversity within V. inaequalis isolates. Three major clusters were obtained and the isolates could not be categorized on the basis of either their geographical distribution or the cultivar from which they were isolated. amova analysis of pathogen populations at regional or race level revealed high diversity within the populations. Pairwise F_ST comparisons between the populations revealed less genetic differentiation, thereby indicating existence of frequent gene flow in Kashmir. The 24 rDNA sequences of V. inaequalis showed high haplotype diversity of 0.938 and 0.40 nucleotide diversity. Again clustering at regional or race level detected greater part of variability within groups than among groups, thereby indicating high diversity in V. inaequalis populations in Kashmir valley.     

福建栽培大豆品种RAPD标记多样性分析

利用RAPD分子标记技术对福建18份栽培大豆品种遗传多样性进行研究.结果表明,12个引物共扩增出91条带,其中多态条带65条,多态性程度为71.43%.D=0.62时,聚类分析结果可以将供试材料分为3个大类群,即菜用大豆品种、杂交育成品种和地方品种、有半野生血缘的品种各聚成1类,揭示了福建省栽培大豆品种间的亲缘关系,同时还反映出品种间关系与地理起源有一定的相关.     

猕猴桃属16个雄性材料遗传多样性的ISSR分析

利用ISSR分子标记对雄性猕猴桃16个材料进行遗传多样性分析。从100条引物中筛选出10条引物用于ISSR扩增,共扩增出172条带,其中多态性条带140条,多态性百分率为81.4%;经POPGENE 1.32软件分析结果显示,16个雄性猕猴桃材料的遗传距离在0.1503~0.5128之间,平均Nei's基因多样性指数(H)为0.2416,平均Shannon信息指数(I)为0.4048;聚类分析结果显示,在遗传相似系数为0.64处可将供试材料分成4类,第Ⅰ类为中华和美味猕猴桃,第Ⅱ类为阔叶、毛花猕猴桃,第Ⅲ类为魁绿猕猴桃,第Ⅳ类为四萼猕猴桃。结果表明ISSR可用于雄性猕猴桃遗传多样性研究,该研究结果可为猕猴桃种质资源的进一步开发利用提供重要信息。     

中国东北地区水稻主要栽培品种的遗传多样性分析

利用68对SSR引物对91份粳稻品种进行了遗传多样性分析。研究结果共检测到293个等位基因,平均4．3个;平均多态信息含量（PIC）为0．313,变动范围为0．022～0．825。RM333和RM206的等住基因数最多,分别为14、10;且PIC也最高,分别为0．825、0．805。聚类和群体差异分析结果表明,东北三省水稻品种的遗传基础狭窄。黑龙江省和吉林省、黑龙江省和日本、吉林省和日本的水稻品种间遗传距离都很小．分别为0．083、0．084、0．090,而辽宁省与吉林省、黑龙江省的水稻品种遗传基础有一些差异。9个地理来源的品种聚类结果,可分为5个大类群,黑龙江省、吉林省、日本和韩国形成第Ⅰ类群;北京和辽宁省归为第Ⅱ类群;中国台湾、云南省、美国分别为第Ⅲ、第Ⅳ和第Ⅴ类群。东北三省是重要的粳稻生产基地,但遗传基础非常狭窄,要克服遗传脆弱性应从地理位置较远的国家或地区收集更丰富的遗传资源。     

中国主要黑芝麻品种的遗传多样性分析

利用SRAP和SSR各23对引物对20个中国主要黑芝麻品种进行了遗传多样性分析。结果显示,23对SRAP引物共扩增出DNA带672条,其中多态性带152条,比率为22.62%,平均每对引物扩增总带数和多态性条带分别为29.22条和6.61条。23对SSR多态性引物共扩增出DNA带92条,每对引物扩增出3~6条,平均4.00条;每对引物扩增出多态性带1~5条,平均3.09条,多态性带比率平均为77.17%。20个黑芝麻品种间的遗传相似系数为0.8547~0.9804,遗传距离为0.0159~0.0921,遗传多样性匮乏,遗传基础狭窄。聚类结果表明,来自主产区江西的11个品种明显聚在一起,且江西黑芝麻品种的遗传相似系数高于其他省份品种,遗传距离低于其他省份品种,与其他省份品种的差异均达到极显著水平。加强资源引进和利用是拓宽中国黑芝麻品种遗传基础的迫切要求。     

利用SRAP标记分析河南小麦栽培品种的遗传多样性

利用小麦SRAP标记对22个河南省小麦品种进行了遗传多样性分析,10对引物组合扩增获得169个条带,其中70个条带具有多态性,多态条带百分率为41．42％,每对引物平均产生7个多态性条带。22个供试材料的带型按照条带的有、无分别记录为1、0后,采用Nei72方法计算不同品种的遗传距离,利用NTSYS软件进行非加权组法（UPGMA）聚类分析。结果表明SRAP标记技术能较真实地反映小麦品种间的亲缘关系,可以用于小麦品种遗传多样性研究。     

芝麻核心收集品中育成品种（系）的遗传多样性分析

利用SRAP分子标记技术对中国芝麻核心收集品的育成品种(系)进行遗传多样性分析,结果表明,14对引物组合在18份芝麻育成品种(系)间共扩增出稳定清晰的条带193条,其中多态性带124条,占64.2%.通过聚类分析和主坐标分析,表明育成品种(系)的遗传基础存在一定的多样性,但遗传相似系数较大(0.5342～0.9688),遗传距离较近.该研究结果表明,在芝麻育种的亲本选配中应积极引入地方种质、国外种质等,以拓宽遗传基础.     

Genetic Diversity and Population Structure Among Oat Cultivars and Landraces

In this study, genetic diversity among 177 oat (Avena sativa L.) accessions including both white and red oat landraces and 36 commercial cultivars was studied for simple sequence repeat (SSR) loci. Thirty-one genomic and expressed sequence tags (EST)-derived primer pairs were selected according to high polymorphism from an initial 66 SSR batch. Markers revealed a high level of polymorphism, detecting a total of 454 alleles. The average gene diversity for the whole sample was 0.29. Genetic similarity, calculated using the Dice coefficient, was used for cluster analysis, and principal component analysis was also applied. In addition, population structure using a Bayesian clustering approach identified discrete subpopulation based on allele frequency and showed similar clustering of oat genotypes in four groups. Accessions could be classified into four main clusters that clearly separated the commercial cultivars, the red oat landraces and two clusters of white oat landraces. Cultivars showed less diversity than the landraces indicating a reduction of genetic diversity during breeding, whereas white oat landraces showed higher diversity than red ones. The average polymorphic information content of 0.80 for the SSR loci indicated the usefulness of many of the SSR for genotype identification. In particular, two markers, MAMA5 and AM04, with a total of 50 alleles and a high discrimination power (>0.90), were sufficient to discriminate among all commercial cultivars studied highlighting their potential use for variety identification.     

不同品种牡丹ISSR遗传多样性分析

旨在为牡丹的合理利用及其资源管理奠定基础。对洛阳地区35个品种的牡丹进行遗传多样性分析。利用改良的CTAB法和ISSR-PCR来提取DNA以及进行DNA扩增,从UBC公布的220条ISSR引物中最后筛选出了12条扩增条带清晰的引物。筛选后总共获得了130条清晰的扩增条带,多态性条带的占比为96.1%。统计条带之后,使用popgene32分析得出35种牡丹的平均Shannon信息指数H=0.465 9,平均Nei’s基因多样性指数He=0.294 5,说明35个牡丹品种遗传多样性丰富。利用NTSYSpc-2.10e分析软件进行聚类分析后,将洛阳的35个牡丹品种分为5大类。实验中的35种牡丹在进行分类时并不一定按照花色进行分类,只有在亲缘关系较近时才会聚在一起。     

Molecular Genetic Diversity of Major Indian Rice Cultivars over Decadal Periods

Genetic diversity in representative sets of high yielding varieties of rice released in India between 1970 and 2010 was studied at molecular level employing hypervariable microsatellite markers. Of 64 rice SSR primer pairs studied, 52 showed polymorphism, when screened in 100 rice genotypes. A total of 184 alleles was identified averaging 3.63 alleles per locus. Cluster analysis clearly grouped the 100 genotypes into their respective decadal periods i.e., 1970s, 1980s, 1990s and 2000s. The trend of diversity over the decadal periods estimated based on the number of alleles (Na), allelic richness (Rs), Nei’s genetic diversity index (He), observed heterozygosity (Ho) and polymorphism information content (PIC) revealed increase of diversity over the periods in year of releasewise and longevitywise classification of rice varieties. Analysis of molecular variance (AMOVA) suggested more variation in within the decadal periods than among the decades. Pairwise comparison of population differentiation (Fst) among decadal periods showed significant difference between all the pairs except a few. Analysis of trends of appearing and disappearing alleles over decadal periods showed an increase in the appearance of alleles and decrease in disappearance in both the categories of varieties. It was obvious from the present findings, that genetic diversity was progressively on the rise in the varieties released during the decadal periods, between 1970s and 2000s.     

茄子耐盐种质资源遗传多样性的SRAP和ISSR分析

利用SRAP和ISSR分子标记,研究了14份耐盐茄子种质资源的遗传多样性,结果表明,2种标记均能揭示材料间较高的遗传多样性,其中ISSR标记多态性略高于SRAP标记。在SRAP分析中,每对引物组合可扩增出8-15条DNA片段,平均为12．12条：26对SRAP引物组合共扩增出315条DNA片段,其中263条具有多态性,多态性比率为83．49％;材料间遗传相似系数变化范围为0．212～0．923,平均值为0．755。在ISSR分析中,每个引物可获得5～16条DNA片段,平均为10．87条;15个ISSR引物共扩增出163条DNA片段,其中141条具有多态性,多态性比率为86．50％;材料间遗传相似系数变幅为0．333-0．957,平均值为0．736。聚类分析表明,2种标记都能将供试材料完全区分开来,聚类结果具有一定的相似性,但也存在明显差异。Mantel相关分析表明,SRAP分析与ISSR分析的相关性达到极显著性水平（r=0．904,P〈0．01）。