分子标记技术在西瓜遗传育种上的应用

西瓜是世界上重要的水果之一.分子标记技术在西瓜研究中的应用,无疑给西瓜的遗传育种工作带来了极大的便利.目前,已成功应用于西瓜亲缘关系和遗传多样性分析、图谱构建、重要性状基因的连锁标记和杂种纯度鉴定等诸多领域,本文从种质资源遗传多态性与亲缘关系、遗传图谱的构建、目标性状的连锁分子标记与分子标记辅助育种、品种及杂交种纯度鉴定等方面展开综述,探讨近年来分子标记技术在西瓜遗传育种上的应用研究进展.     

花卉遗传连锁图谱构建与QTL定位的研究进展

近年来,随着分子生物学特别是分子标记技术的飞速发展,花卉的育种工作开始由传统的杂交育种逐渐转变为分子育种。而建立遗传连锁图谱、定位QTL等分子标记辅助育种已经成为近年植物分子育种的研究热点之一。目前,遗传连锁图谱的构建多集中在农作物及林木领域,花卉的遗传连锁图谱还处于发展阶段。构建高密度的遗传连锁图谱和精细的QTL定位能够加快花卉的育种研究。本研究综述了国内外花卉遗传连锁图谱构建的研究进展,包括构建遗传连锁图谱所需要的亲本和分离群体,主要使用的分子标记方法,花卉遗传连锁图谱中的QTL定位,并对花卉遗传连锁图谱构建中存在的问题进行了探讨,对今后的发展提出了一些建议并对研究前景进行了展望。     

性状相关的分子标记在甘蔗分子育种中的应用研究

分子设计育种在农作物品种改良中发挥了重要作用,但由于甘蔗基因组庞大且高度杂合,染色体呈非整倍性,导致其性状相关的分子标记辅助育种进展十分缓慢。为加快甘蔗育种进程,提高其育种效率和准确性,简述了甘蔗分子标记辅助育种现状及其瓶颈,并总结了应用于甘蔗的分子标记种类及其问题,阐明分子标记在甘蔗遗传连锁图谱构建中的作用,进而从甘蔗产量和糖分性状相关QTL的定位、主要抗病基因（抗褐锈病基因、抗黑穗病和抗黄斑病基因）的定位及其在抗病分子育种上的应用,以及关联分析方法在甘蔗重要性状研究中的应用等方面对性状相关的分子标记进行综述。最后对甘蔗重要性状相关分子标记辅助育种的机遇和挑战进行了展望,为甘蔗分子育种的深入研究提供理论依据。     

分子标记在裸子植物应用中的研究进展

分子标记技术应用于裸子植物研究,对裸子植物亲缘关系与遗传多样性研究、分子辅助育种、遗传图谱构建及资源保护利用等研究带来了极大的便利。本文从种质遗传多态性及亲缘关系、遗传图谱构建、目标性状连锁分子标记与辅助育种、种质与性别鉴定等方面展开综述,探讨近年来分子标记在裸子植物应用中的研究进展,并讨论了分子标记在裸子植物研究上存在的问题。     

苦荞SSR分子遗传图谱的构建及分析

构建苦荞遗传连锁图谱,为今后有关苦荞基因组结构、重要农艺性状QTL定位、分子标记辅助育种和基因克隆等研究工作奠定基础。以栽培苦荞‘滇宁一号’和苦荞野生近缘种杂交产生的119份F4代分离材料为作图群体,利用SSR分子标记来构建苦荞的分子遗传连锁图谱。本研究构建的连锁图谱包含15个连锁群,由89个标记组成,其中偏分离的标记有22个,占24.7%,每条连锁群上的标记在2~16之间。连锁群长度在6.9~165.8 cM的范围,覆盖基因组860.2 cM,总平均长度9.7 cM。本研究构建了首张苦荞SSR遗传连锁图谱,为苦荞QTL定位、基因克隆、遗传选育等研究奠定了基础。     

分子标记在松树遗传与进化研究中的应用

松树是世界上分布最广且最具经济价值的树种之一。近年来随着DNA分子标记技术的发展,分子标记已经广泛应用于松树的遗传多样性、亲缘关系、遗传图谱构建、基因定位及分子标记辅助选择等方向。本文从遗传多样性、亲缘关系、遗传图谱构建、基因定位及标记辅助选择等角度,评述了松树遗传与进化上常用的DNA分子标记如RFLP、RAPD、AFLP和SSR等的应用情况和进展。在遗传多样性方面,DNA分子标记技术已成为鉴定松树种间、种内遗传多样性的有效手段,并用于指导杂交育种;在亲缘关系判定方面,可以在分子水平上阐明生物系统演化及分类情况,揭示育种亲本的选配和种质资源的有效利用;在松树遗传图谱构建和基因定位及标记辅助选择方面也取得了显著进展,构建了二十多张连锁图谱,并对其生长、材性和抗性等性状进行了基因定位,获得了一些重要的与抗病相连锁标记。     

红花分子标记研究进展

红花是药食同源的经济作物,不但花瓣色素提取物可用于医药原料、化妆品和食品染料等方面,而且红花油是优质保健食用油,具有重要的医药价值和食用价值。DNA分子标记在红花育种中已得到广泛应用,并取得了丰硕成果。本综述简要概括DNA分子标记技术的主要特点,从红花种质资源评价、遗传多样性分析、目标基因定位及苞叶刺性状基因研究等方面总结DNA分子标记在红花育种研究中的进展,并对将来红花的研究方向、重点及领域进行简要分析和探讨。红花未来分子生学研究要结合现代高通量测序技术,采用精细SNP等分子标记或转录组测序手段,寻找与经济、药用性状紧密连锁的分子标记构建红花遗传连锁图谱和定位、分离目标性状基因,为红花分子标记辅助选择育种(MAS)提供研究基础,提高红花育种的效率。     

SSR分子标记在小麦遗传育种中应用与研究进展

综述简单重复序列标记(SSR)的特点及优点,重点介绍了SSR分子标记在小麦遗传育种中的应用,即利用SSR分子标记技术基因标记与定位、遗传图谱构建、外源染色体鉴定与标记、种质资源鉴定和遗传多样性研究、辅助育种的研究进展。     

DNA分子标记在洋葱遗传育种研究中的应用

DNA分子标记技术的出现大大提高了遗传分析的准确性和选育品种的有效性,在植物遗传育种领域越来越受到重视.洋葱属于二年生植物,一个世代需要三年,具有育种年限长的问题.利用分子标记辅助选择是缩短洋葱育种年限,加快育种进程极其有效的途径.本文综述了DNA分子标记技术在洋葱遗传图谱构建、遗传多样性分析、种质鉴定、鉴定洋葱细胞质类型、重要性状的分子标记辅助选择和数量性状的基因定位等方面的应用,讨论了洋葱遗传育种中分子标记技术的现状及存在的问题,并对洋葱分子标记辅助育种的应用前景进行了展望.指出洋葱高密度的遗传图谱还有待于建成,对于数量性状标记的鉴定,还有待于进一步开发、快速和准确定位的QTL,关于洋葱抗病基因的标记需要深入研究.     

枣4种农艺性状的QTL定位及分析

为了加快中国枣种质资源改良进程,以定位和分析枣农艺性状QTL为目标,分别调查了中心干直径、二次枝着生角、二次枝弯度和二次枝曲度性状表型值在150株‘冬枣’ב临猗梨枣’F1代群体中的分离情况,并应用已构建的枣遗传连锁图谱,采用区间作图法实现了枣4种农艺性状的QTL分析。共检测到4种性状相关的QTL 34个,包含控制中心干直径10个、控制二次枝着生角度5个、控制二次枝弯度8个和控制二次枝上曲度3个。34个QTL分布在枣遗传连锁图谱的11个连锁群中,各QTL的LOD值在2.50~4.61之间,可分别解释8.6%~54.2%的表型变异。这些枣农艺性状QTL的定位以及相关信息的获得将为今后开展枣相关基因的图位克隆、品种改良及分子标记辅助育种提供十分重要的工具和基础。     

An introduction to markers, quantitative trait loci (QTL) mapping and marker-assisted selection for crop improvement: The basic concepts

Recognizing the enormous potential of DNA markers in plant breeding, many agricultural research centers and plant breeding institutes have adopted the capacity for marker development and marker-assisted selection (MAS). However, due to rapid developments in marker technology, statistical methodology for identifying quantitative trait loci (QTLs) and the jargon used by molecular biologists, the utility of DNA markers in plant breeding may not be clearly understood by non-molecular biologists. This review provides an introduction to DNA markers and the concept of polymorphism, linkage analysis and map construction, the principles of QTL analysis and how markers may be applied in breeding programs using MAS. This review has been specifically written for readers who have only a basic knowledge of molecular biology and/or plant genetics. Its format is therefore ideal for conventional plant breeders, physiologists, pathologists, other plant scientists and students.     

栽培绿豆V1128抗豆象基因定位

对抗豆象资源中蕴藏的抗豆象基因进行定位, 是对其充分利用的前提和基础。本研究通过对抗豆象栽培绿豆V1128和感豆象栽培绿豆冀绿7号杂交形成的F₂分离群体进行抗豆象鉴定, 分析V1128抗豆象遗传规律; 并利用混合群体分离分析法(BSA法)筛选抗感池间的多态性标记, 进而利用QTL IciMapping 4.0对V1128抗豆象基因进行染色体定位分析。结果表明, V1128对绿豆象的抗性由具有主效作用的显性单基因控制, 暂命名其为“Br3”。在将抗豆象性状作为质量性状的条件下, 按照显性单基因的定位方法, 将抗豆象基因Br3定位在绿豆染色体5上, 位于标记DMB158和VRBR-SSR033 (标记VRID5、VRBR-SSR032与VRBR-SSR033的连锁群位置相同)之间, 两侧遗传距离分别为4.4 cM和5.8 cM, 所在物理区间约288 kb。将抗豆象性状作为数量性状, 采用完备区间作图法(ICIM)对种子被害率进行QTL定位, 同样在标记DMB158和VRBR-SSR033之间检测到1个主效QTL, 其LOD值为38.04, 可以解释表型变异(PVE)的71.64%, 来自父本V1128的等位基因具有明显减少种子被害率的效应。该研究结果可以为绿豆抗豆象分子标记辅助育种及抗豆象基因Br3的精细定位和克隆提供有用信息。     

DNA分子标记技术在烟草遗传育种中的应用

从种质资源研究、遗传图谱构建、基因定位及分子标记辅助选择等方面综述了DNA分子标记技术在烟草遗传育种中的应用,并分析了分子标记技术在烟草遗传育种研究中存在的问题及应用前景。     

QTL mapping and marker-assisted selection for Fusarium head blight resistance in wheat: a review

During the past decade, numerous studies have been published on molecular mapping of Fusarium head blight (FHB) resistance in wheat. We summarize the relevant findings from 52 quantitative trait loci (QTL) mapping studies, nine research articles on marker-assisted selection and seven on marker-assisted germplasm evaluation. QTL for FHB resistance were found on all wheat chromosomes except chromosome 7D. Some QTL were found in several independent mapping studies indicating that such QTL are stable and therefore useful in breeding programmes. We summarize and update current knowledge on the genetics of FHB resistance in wheat resulting from QTL mapping investigations and review and suggest FHB breeding strategies based on the available information and DNA markers.     

Development of high-density interspecific genetic maps for the identification of QTLs conferring resistance to <Emphasis Type="Italic">Valsa ceratosperma</Emphasis> in apple

Valsa canker (Valsa ceratosperma (Tode ex Fr.) Maire) is one of the most destructive fungal diseases of apple, especially in Eastern Asia. In this study, the first high density genetic linkage map of Malus asiatica × Malus domestica was constructed by 640 simple sequence repeats (SSRs) and 490 single nucleotide polymorphisms (SNPs), which spanned 1497.5 cM with an average marker interval of 1.33 cM per marker. Quantitative trait loci (QTLs) for apple’s resistance to V. ceratosperma isolates 03-8 and xc56 were identified using the linkage map. Lesion lengths were used as the phenotypic data for the QTL analysis, which were measured on 1-year-old shoots inoculated with conidia of the two isolates. One QTL for resistance to isolate 03-8 was mapped on LG 16, and one QTL for resistance to isolate xc56 was detected on LG 9. Our research not only promoted the further understanding of the genetic basis of apple’s resistance to Valsa canker but also provided two molecular markers that might be used in future marker-assisted selection for resistance in apple breeding programs.     

Breeding for boron tolerance in lentil (Lens culinaris Medik.) using a high‐throughput phenotypic assay and molecular markers

This study describes the identification of a quantitative trait locus (QTL) in the recombinant inbred line population of ILL2024 × ILL6788 and subsequent validation of associated molecular markers. A high‐quality genetic linkage map was constructed with 758 markers that cover 1,057 cM, with an average intermarker distance of 2 cM. QTL analysis revealed a single genomic region on Lc2 to be associated with B tolerance and accounted for up to 76% of phenotypic variation (Vp). The best markers for B tolerance were assessed for their utility in routine breeding applications using validation panels of diverse lentil germplasm and breeding material derived from ILL2024. A marker generated from the dense genetic map of this study was found to be the most accurate of all markers available for B tolerance in lentil, with a success rate of 93% within a large breeding pool derived from ILL2024. However, given the number of the unrelated lines for which the marker–trait association was not conserved, B tolerance screening is still required at later stages to confirm predicted phenotypes.     

分子标记技术在辣椒研究中的应用进展

分子标记是生物学研究的一个重要工具,在作物新品种选育等方面发挥着越来越重要的作用。为了构建辣椒分子标记辅助育种技术体系,以实现常规育种技术与现代生物技术的有机结合,归纳了分子标记技术在辣椒种质遗传多样性、分子连锁图谱构建、分子标记辅助选择育种和基因定位等方面的已有研究成果;认为分子标记技术在辣椒上的应用研究系统性还不强、基础分子信息比较缺乏、遗传图谱还不精细,建议在实用新型分子标记开发、核心种质分子信息库建立、优良作图群体及精细遗传图谱构建等方面加强系统深入的研究。     

An SSR-based molecular genetic map of cassava

Summary Microsatellites or simple sequence repeats (SSR) are the markers of choice for molecular genetic mapping and marker-assisted selection in many crop species. A microsatellite-based linkage map of cassava was drawn using SSR markers and a F₂ population consisting of 268 individuals. The F₂ population was derived from selfing the genotype K150, an early yielding genotype from an F₁ progeny from a cross between two non-inbred elite cassava varieties, TMS 30572 and CM 2177-2 from IITA and CIAT respectively. A set of 472 SSR markers, previously developed from cassava genomic and cDNA libraries, were screened for polymorphism in K150 and its parents TMS 30572 and CM 2177-2. One hundred and twenty two polymorphic SSR markers were identified and utilized for linkage analysis. The map has 100 markers spanning 1236.7 cM, distributed on 22 linkage groups with an average marker distance of 17.92 cM. Marker density across the genome was uniform. This is the first SSR based linkage map of cassava and represents an important step towards quantitative trait loci mapping and genetic analysis of complex traits in M. esculenta species in national research program and other institutes with minimal laboratory facilities. SSR markers reduce the time and cost of mapping quantitative trait loci (QTL) controlling traits of agronomic interest, and are of potential use for marker-assisted selection (MAS).