应用SSR标记对小豆种质资源的遗传多样性分析

利用24对SSR引物对158份栽培小豆及18份野生小豆资源进行遗传多样性分析。结果表明,栽培小豆的遗传变异水平显著低于野生小豆,其中18对引物在栽培小豆中能检测到多态性,平均等位变异数为3.0个,21对引物在野生小豆中能检测到多态性,平均等位变异数为2.6个。栽培小豆种质间平均遗传相似性系数为0.724,野生小豆间为0.605。基于类平均法的聚类分析可以将栽培小豆和野生小豆区分开,这与主坐标分析的结果基本吻合。不同来源的栽培小豆群体间也有一定的遗传分化。SSR分析不仅验证了小豆品种间的遗传背景与其系谱来源相吻合,而且揭示了同名种质天津红小豆之间的遗传差异。本研究为我国小豆种质资源育种及SSR标记在小豆多样性分析、基因标记、品种鉴定等工作提供了信息。     

普通豇豆应用核心种质的SSR指纹图谱构建及多样性分析

不同种质资源群体的多样性及遗传背景分析可为种质资源收集保存及创新利用提供有效信息。对不同来源的88份普通豇豆应用核心种质资源进行了14个SSR位点的指纹图谱构建及多样性分析,共检测到39个等位变异,每对引物检测到2~5个,平均为2.79。多态信息含量（PIC）变幅为0.25~0.72,平均为0.58。UPGMA聚类结果显示,除了3对种质外,39个等位变异可将其他材料有效区分,且在遗传相似系数为0.63时,88份种质可分为4个类群,地理来源相同的材料有聚在一起的趋势。     

利用SSR标记分析野生小豆及其近缘野生植物的遗传多样性

利用28对SSR引物对96份野生小豆资源、小豆近缘野生植物及栽培小豆品种进行遗传多样性分析,共检测到255个等位变异,平均每对SSR引物9.10个,多态信息含量的变异范围从0.374到0.865,平均为0.722。野生小豆材料和近缘植物Vigna minima遗传变异丰富。来自不同地域的野生小豆材料具有大量特异等位变异,基于非加权成组配对算术平均法的聚类分析可将不同地理来源的野生小豆单独分群,且与主坐标分析的结果相一致。4份栽培小豆材料与日本野生小豆遗传距离较近,表明目前国内小豆育种中较多使用了含有日本血缘的小豆材料,以及国内野生小豆资源的搜集和利用工作落后于日本。本研究对国内野生小豆资源的搜集和保存具有指导意义,并可以为这些资源的评价、利用和优异基因的发掘提供参考。     

基于SSR标记的饲草高粱种质资源遗传多样性分析

为了研究饲草高粱品种之间的遗传关系,本研究利用109对SSR引物对48个饲草高粱种质资源进行遗传多样性分析。结果表明,109对SSR引物在3%琼脂糖凝胶上共检测出300个等位变异,平均每个位点检测到3.08个等位变异。平均多肽信息量为0.605 6,多态性信息指数变幅为0.268 0~0.901 2。通过聚类分析将48个高粱品种分为2个类群。分类结果和已知系谱的亲源关系多数吻合,说明供试的饲草高粱种质资源具有较为丰富的遗传多样性。本研究旨在对饲草高粱种质资源的有效利用提供帮助和参考。     

基于SSR标记的板栗种质资源遗传多样性分析

本研究利用筛选出的21对SSR分子标记对来自12个省(市)的279份板栗资源进行遗传多样性分析,为种质资源的开发利用与核心种质的构建提供科学依据。结果表明:21对引物共检测到71个等位变异位点,变异范围为2～6,平均每对SSR引物可检测到3.38个等位位点;多态性信息含量变化范围在0.614 5～0.972 3之间,平均0.866 8。通过检测10个群体的遗传多样性参数,发现山东群体Shannon's信息指数(I=0.487 0)、Nei's多样性指数(H=0.319 5)、有效等位基因数(Ne=1.530)及多态位点百分率(PPB=100%)均最大,是遗传多样性最丰富的群体;群体间遗传分化系数Gst=0.099 3,表明群体内遗传分化大于群体间分化;基因流Nm=4.536 1,说明板栗各群体间存在适度的基因交流;聚类结果和主坐标分析图表明,各群体的遗传关系和地理来源有一定联系。     

利用SSR荧光标记技术分析烟草种质的遗传多样性

针对中国烟草栽培品种遗传基础狭窄的情况,分析烟草种资资源的遗传多样性将可为烟草新品种选育、引种和资源保护提供重要信息。据此,利用20个SSR引物组合,采用荧光SSR标记法对来自不同国家和地区的50个烟草种质材料的遗传多样性进行分析。研究结果显示,20对SSR引物在50份烟草种质中检测到81个等位变异,平均每个SSR为4.1,平均多态性位点比率为68.4%;其中引物PT20457的鉴别能力最高,它的扩增多态位点数为6个,多态位点比率为100%,PIC值为0.944。研究的UPGMA聚类分析结果在遗传相似系数约为0.65处将50份烟草种质明显分成了3个组群,组群Ⅰ中只有1个广东晒烟,组群Ⅱ包括2个白肋烟,组群Ⅲ包括来自4个国家的47个品种。主坐标分析将所有种质分成了4个组群8个亚类。2种分析方法均较好地揭示了烟草属种间或栽培种品种类型间的遗传多样性与亲缘关系,可为烟草遗传育种和遗传连锁图谱构建的杂交亲本选择提供科学依据。     

芝麻种质资源SSR标记遗传多样性与群体结构

利用42对具明显多态性的SSR引物, 分析国内外545份芝麻品种的遗传多样性和群体结构。结果检测到106个等位变异位点, 引物多态位点范围为3~9个, 平均为3.8个/引物, Y1994引物的等位位点最多, 为9个。引物Shannon信息指数(I)范围为1.4834~0.1233, 平均值为0.6450; 多态信息指数(PIC)范围为0.7481~0.0516, 平均值为0.4092, 平均杂合度(He)为0.1162。UPGMA聚类、二元主成分及群体结构分析结果基本一致; 供试545份芝麻资源可被分为3个UPGMA组群, 在群体结构上分为3个亚群; 芝麻资源整体遗传分化较小, 亲缘关系较近。中国7个生态群种质相似系数范围为0.9811~0.5462, 东北西北等区域资源与黄淮、江汉、华中华南等区的亲缘关系较远; 国外7个生态群相似系数为0.9726~0.7442, 非洲区与日本区种质亲缘关系较近, 与中国资源亲缘关系较远。中国种质资源遗传基础较为狭窄, 遗传多样性与地理分布不完全相关, 而国外资源遗传多样性丰富。在今后芝麻育种工作中, 应加强国外资源的引进与利用, 并注重国内不同类群资源利用, 拓宽我国芝麻品种遗传基础。     

小豆SSR引物在绿豆基因组中的通用性分析

分析了187对小豆SSR引物在绿豆基因组中的可转移性,以期为绿豆分子遗传育种研究提供分析工具.结果表明,约75%的小豆SSR引物可在绿豆中有效扩增,但不同小豆连锁群SSR引物的可转移率存在差异.多态性分析发现80对引物中有28对在60份绿豆种质中可以检测到多态性,等位变异数从2～7不等,平均为2.9,PIC指数从0.02～0.69,平均为0.36.UPGMA聚类及主坐标分析表明,尽管同一省份的种质不能紧密聚在一起,但大多在聚类图上成簇状分布,说明相同来源的绿豆种质具有相似的遗传背景;此外,国外及我国边远地区的绿豆种质在遗传背景上与内部省份间存在明显差异.这些多态性SSR不仅可以有效用于绿豆分子遗传学研究,还可以用于不同来源绿豆种质资源的辅助鉴别.     

基于SSR分子标记技术的欧榛品种遗传多样性分析

遗传多样性研究是种质资源保护和利用的基础。为探索欧榛品种间的遗传关系,利用SSR分子标记技术,对‘Corabel’、‘Kentish’和‘Carrifran’3个品种共55份供试材料进行遗传多样性分析。结果表明:3对SSR引物在55份供试材料中共检测到44个等位基因,位点可检测到等位基因数(Na)为11～17个,平均每个位点可检测到14.67个等位基因;平均观测杂合度(Ho)、平均期望杂合度(He)分别为0.62和0.87;多态信息量(PIC)变化范围为0.81～0.90,平均为0.86;利用算术加权平均数法(UPGMA)将55份材料分为4大类群。研究表明,欧榛品种间遗传多样性水平较高,这为新品种选育提供了科学依据。     

贵州108份地方玉米品种的SSR遗传多样性分析

利用19对玉米SSR核心引物对108个贵州地方玉米种质材料进行了SSR多样性分析。共检测186个等位基因,每对引物检测到5～15个多态性片段,平均为9.8个;每个位点SSR多态信息量(PIC)变化为0.70～0.90,平均为0.82。遗传相似性系数在0.44～0.99之间。通过聚类分析可将供试材料划分为5个类群,实验结果显示出贵州玉米种质的遗传基础较为广泛。     

41份非洲和湖北蚕豆种质资源SSR遗传多样性分析

为研究蚕豆的遗传多样性,选用50对引物,对41份非洲和湖北蚕豆种质资源进行SSR遗传多样性分析。引物的PIC值介于0.28~0.91之间,平均值为0.68,50对引物共获得扩增DNA条带249条,多态性条带(等位基因)为246条。利用NTSYS软件对41份非洲和湖北蚕豆种质SSR数据进行聚类分析。在D-0.6957处将41份种质资源分为三大类群。第Ⅰ类(13个品种)为埃及和埃塞尔比亚的材料;第Ⅱ类(12个品种)主要为苏丹的材料;第Ⅲ类(16个品种)包括所有湖北地区的材料。通过Structure群体结构分析结果与聚类分析结果高度吻合。本研究结果可为蚕豆种质资源的收集和利用以及进一步开发利用SSR标记提供参考。     

小豆遗传差异、群体结构和连锁不平衡水平的SSR分析

利用57对小豆SSR标记和31对绿豆SSR标记,用5份日本材料作对照,对249份中国小豆种质进行遗传差异、群体结构和连锁不平衡(LD)分析。结果表明,共检测到630个等位变异,SSR位点等位变异数在2~17之间,遗传多样性指数范围为0.024~0.898,平均为0.574。15个不同地理来源群体间表现出显著的遗传多样性差异,其中中国云南最高,河北、天津最低。聚类分析将254份材料划分为3个类群,在一定程度上和地理生态环境相关。LD分析显示和其他作物相比,小豆LD衰减距离较短,最大衰减距离为5.8 cM (R²>0.1),基因组LD平均衰减距离小于1 cM (R²>0.1,P<0.001)。     

Genetic diversity of Chinese Spring Soybean Germplasm Revealed by SSR Markers

To use, maintain and increase crop germplasm collections efficiently, it is important to assess the diversity of these collections. In this study, 1383 accessions of Chinese spring sowing soybean ( Glycine max ) were used for SSR analysis. In total, 1111 alleles were detected among these collections with an average number of alleles (NA) of 18.52 per locus. The genetic diversity index (PIC value) varied from 0.456 to 0.928 with an average of 0.815. Intensive breeding of cultivars have led to a decrease of genetic diversity. Random-repeated sampling within landraces of different geographical regions suggested that the ranking of both average NA and PIC values among different geographical regions were North spring soybean (Nsp) > South spring soybean (Ssp) > Northeast spring soybean (NEsp), but because of the uneven distribution of SSR variation patterns, the differences between them did not reach a significant level. There was a relationship between genetic distances and geographical distances among soybean populations from different regions, indicating a certain degree of geographical differentiation among Chinese soybean germplasm collections.     

Isolation and characterization of 28 polymorphic SSR loci from castor bean (<Emphasis Type="Italic">Ricinus communis</Emphasis> L.)

Castor bean (Ricinus communis) is cultivated for seed oil throughout tropical and subtropical regions but the understanding of its genetic variability is limited. Because applicable microsatellite markers are not sufficient, we isolated and characterized polymorphic simple sequence repeat (SSR) loci acquired from a microsatellite-enriched genomic DNA library of castor bean. Finally, 28 SSR loci revealed polymorphisms in a castor bean collection consisting of 72 accessions. A total of 73 alleles were detected, with an average of 3.18 alleles per locus, and the polymorphism information content (PIC) ranged from 0.03 to 0.47 (mean = 0.26). Values for observed (H_O) and expected (H_E) heterozygosity ranged from 0.00 to 0.19 (mean = 0.11) and from 0.04 to 0.54 (mean = 0.31), respectively. To understand genetic relationships within the castor bean collection, a dendrogram was constructed based on profiles of the 28 SSR loci. These newly developed SSRs will be useful tools for assessing genetic diversity and population structure in castor bean.     

Analysis of population structure and genetic diversity in balloon flower (Platycodon grandiflorum (Jacq.) A. DC.) germplasm using Simple Sequence Repeat (SSR) markers

Balloon flower (Platycodon grandiflorum A. DC) is widely distributed in South Korea and there are some local landraces that are cultivated as a vegetable crop or medicinal plant. Making use of the gene resources of wild-type and landraces is a way to increase the genetic diversity of the cultivars. However, few tools or information are available on an efficient identification system for maintaining and management of these landraces. To improve the genetic resources for balloon flower, 22 simple sequence repeat (SSR) markers, also known as microsatellite markers, were evaluated in a collection of 42 balloon flower landraces, 34 of which were from Korea and eight from China. All microsatellite markers produced the 107 alleles ranging from 2 to 10 with a mean of 4.864 alleles per each locus (N_A). The values of observed heterozygosity (H_O) and expected heterozygosity (H_E) ranged from 0.00 to 0.667 (mean of 0.285) and from 0.024 to 0.741 (mean of 0.416), respectively. An average value of polymorphic information contents (PIC) were 0.382 with a range of 0.023 to 0.703. Results of population structure and phylogenetic and principal coordinate analysis (PCoA) indicated that P. grandiflorum germplasm formed two largely distinct clusters according to their origins and the genetic differentiation. There was a high level of genotypic diversity at broad geographic regions between Korea and China, but the low genetic differentiation was found within the collections from Korea. The results of the genetic diversity will be useful for the selection of the parents for developing balloon flower breeding and the multi-locus SSR markers developed herein will be a valuable resource for germplasm assessments, evaluation of genetic diversity, and population genetic studies of balloon flower.     

Molecular diversity and population structure of the Ethiopian lentil (<Emphasis Type="Italic">Lens Culinaris</Emphasis> Medikus) genotype assessment using SSR markers

Knowledge of genetic diversity in germplasm is essential for formulating effective germplasm collection, conservation, utilization strategies in and crop improvement programs. It also provides an opportunity to take corrective steps infusing new genes to avoid risks associated with a narrow genetic bases. Genetic diversity analysis of 119 lentil genotypes of including 83 germplasm and 36 exotic genotypes from International Center for Agricultural Research in the Dry Areas was studied using 27 primers of simple sequence repeat (SSR) marker. Molecular analysis of variance showed variations of 82% within and 18% of the among population variance was explained. Degree of polymorphism observed among the populations was 100%. A total 122 alleles were detected, with 2 to 7 alleles per locus, with a mean of 4.52 alleles per locus. The estimated gene diversity value for 27 loci was 0.64. The average Shannon’s information index value of 1.19 was obtained showed the existence of high genetic variation within the genotypes. The genetic similarity indices ranged from 0.21 to 1.00. The SSR markers showed an average polymorphic information content (PIC) value of 0.58. Cluster analysis grouped the genotypes into five major clusters as distinct genetic populations. Diversity analyses revealed the existence of a high level of genetic variation among genotypes. This molecular diversity information provides a basis for future germplasm collection, utilization, and conservation strategies in gene banks and introducing exotic germplasm to widen the genetic base of the current lentil breeding population.     

利用SSR标记评价普通菜豆种质遗传多样性

利用36对SSR引物对332份国内普通菜豆、16份国外普通菜豆和29份野生菜豆的遗传多样性进行了分析,等位变异数和多样性指数的计算结果显示,3种生态型普通菜豆遗传多样性由大到小的顺序为国内普通菜豆、野生菜豆和国外普通菜豆;我国贵州、云南、黑龙江等省普通菜豆的遗传多样性较为丰富。基于SSR数据,对377份普通菜豆种质资