普通菜豆抗炭疽病地方品种的朊蛋白标记分析

普通菜豆在长期驯化过程中形成了安第斯和中美两个基因库,研究基因库来源对于抗病育种中抗病亲本的选配具有重要意义.本研究利用菜豆朊蛋白标记分析了54份抗炭疽病菜豆地方品种的基因库来源,基本上明确了我国抗炭疽病菜豆种质的基因源,为抗病育种奠定了基础.     

分子标记在绿豆遗传连锁图谱构建和基因定位研究中的应用

绿豆(Vigna radiata(L.)Wilczek)作为一种医食两用作物,不仅是重要的食物资源,在改善土壤环境、提高农民收入等方面也发挥着重要作用。然而,相对于大宗作物而言,绿豆基础研究薄弱,基因组研究更是落后。近年来,分子标记技术迅速发展,在绿豆基因组学研究中发挥了重要的作用。国内外利用分子标记技术已构建了超过20张绿豆遗传连锁图谱。一些优良基因尤其是与抗性相关的基因被鉴定或精细定位,为绿豆分子标记辅助选择打下基础,加快了抗性新品种的培育进程。本研究通过对分子标记技术在绿豆遗传连锁图谱构建、重要功能基因的定位等方面的应用进行综述,以期为绿豆遗传育种研究及功能基因组学分析提供参考。     

绿豆基因组研究进展

绿豆是亚洲国家重要的经济作物。绿豆基因组的研究工作已开展多年,至今已经发布了6张遗传连锁图谱,然而还未有一张图谱的连锁群数与绿豆(2n=2x=22,n=11)的染色体基数一致。近年来,豆科植物比较基因组学的研究成果,为绿豆遗传连锁图谱的发展提供了新的思路。通过将绿豆遗传连锁图与其他豆类连锁图比较发现,绿豆与小豆、豇豆、普通菜豆、大豆、藊豆以及豆科模式植物—蒺藜苜蓿的基因组间有不同程度的保守性,其中尤以绿豆与普通菜豆基因组间共线性水平高。本文分别从绿豆遗传连锁图谱构建、比较基因组作图以及抗豆象基因定位等方面进行了综述,以期为绿豆遗传研究工作者提供参考。     

重要花卉植物高密度遗传连锁图谱构建研究进展

遗传连锁图谱是以遗传标记间重组频率为基础的染色体或基因组内位点相对位置的线性排列图,高密度遗传图谱构建可实现物理图谱和遗传图谱的整合,对促进基因图位克隆具有重要作用。利用遗传图谱可有效地提高育种效率和改良品种。重要花卉植物高遗传图谱精密度尚无法满足精细定位研究的要求,百合、紫薇、郁金香、向日葵等重要花卉高密度遗传图谱构建研究较少,制约了花卉植物分子育种研究进程。概述了高密度遗传图谱构建流程及作图方法,综述了牡丹、梅花、月季、菊花、兰花、荷花、桂花等重要花卉植物遗传图谱构建研究进展,讨论了重要花卉植物高密度遗传图谱构建存在的主要问题,对今后重要花卉植物遗传图谱构建研究的发展方向及其在育种中的应用前景进行了展望,以期为花卉植物基因定位、辅助基因组组装、比较基因组学、基因克隆、分子标记辅助育种等提供参考。     

栽培一粒小麦3AA30中抗白粉病基因的鉴定及分子标记定位

栽培一粒小麦是普通小麦的近缘种,遗传多样性丰富,蕴含丰富的抗病基因,是小麦抗病性改良的重要资源。本文对栽培一粒小麦抗白粉病材料3AA30的抗白粉病基因进行了遗传分析和分子标记定位。结果表明,3AA30中含有一个隐性抗白粉病基因,暂命名为ml3AA30,找到了5个与该基因连锁的SSR分子标记Xgwm6、Xcfd39、Xcfa2185、Xcfa2141、Xcfa2155及2个STS标记Xmag2170、Xmag1491,并构建了ml3AA30的遗传连锁图,将该基因定位在小麦5A染色体长臂上。本研究为小麦抗病育种提供了新的抗源材料。     

中国植物遗传连锁图谱构建研究进展

遗传连锁图谱构建是基因组研究中的重要环节,是基因定位与克隆乃至基因组结构与功能研究的基础上。近十几年来,分子生物学特别是分子标记技术的飞速发展,为构建高饱和的植物遗传连锁图谱和利用分子标记进行辅助育种奠定了基础。综述了我国在植物遗传连锁图谱构建研究方面的进展及发展动态,列举了我国利用DNA分子标记构建的34张植物遗传连锁图谱实例,且讨论了当前我国在该领域研究中存在的问题并提出了解决途径。     

黄瓜分子标记辅助育种研究进展

本文综述了不同分子标记技术在黄瓜遗传连锁图谱构建、重要性状相关基因的定位、种质资源遗传多样性分析和亲缘关系鉴定、分子标记辅助选择、种子纯度与活力鉴定及其在黄瓜遗传育种等方面的应用,讨论了目前黄瓜遗传育种中应用分子标记技术存在的问题和今后育种工作的重点,并对黄瓜分子标记辅助育种的前景作了展望。     

大豆遗传图谱的构建和分析

利用大豆栽培品种科丰1号和南农1138－2杂交得到的重组近交系NJRIKY,通过RFLP,SSR,RAPD和AFLP4种分子标记的遗传连锁分析,构建了包含24个连锁群,由792个遗传标记组成的大豆较高密度连锁图谱,该图谱覆盖2320．7cM,平均图距2．9cM,SSR标记的多态性较高,在基因组中的位置相对稳定,可以作为锚定标记,有利于连锁群的归并和不同图谱的比较整合;而AFLP标记对于增加图谱密度效率较高,但其容易出现聚集现象,从而造成连锁群上有很大的空隙（gap),另外,在连锁群中有21．7％的分子标记出现偏分离,该图谱为基因定位,比较基因组学和重要农艺性状的QTL定位等研究打下了基础。     

生物技术用于黄瓜遗传育种

“十五”期间,生物技术在黄瓜遗传育种上的应用更加广泛,分子标记辅助育种、单倍体育种以及黄瓜基因工程改良取得了重要进展。本文综述了黄瓜基因分子标记、遗传图谱构建、基因定位、基因克隆与表达、品种DNA指纹图谱分析、分子技术鉴定病害、单倍体和三倍体培养、遗传转化体系建立及基因工程改良方面的最新进展,并讨论了存在的问题和前景。     

豌豆遗传图谱构建及QTL定位研究进展

豌豆的许多性状是多基因控制的数量性状,QTL定位就是以分子标记技术为工具、以遗传连锁图谱为基础、利用分子标记与QTL之间的连锁关系确定控制数量性状的基因在基因组中的位置.本文对QTL定位原理、方法进行了简单介绍;对豌豆遗传图谱构建及主要性状,如产量、品质、抗病性等QTL定位、遗传效应分析等方面的研究进行综述;对目前基于QTL豌豆分子标记育种存在的问题、应用前景进行了探讨.     

Expanding the genetic map of maize with the intermated B73 × Mo17 (IBM) population

The effects of intermating on recombination and the development of linkage maps were assessed in maize. Progeny derived from a common population (B73 × Mo17) before and after five generations of intermating were genotyped at the same set of 190 RFLP loci. Intermating resulted in nearly a four-fold increase in the genetic map distance and increased the potential for improved genetic resolution in 91% of the intervals evaluated. This mapping population and related information should connect research involving dense genetic maps, physical mapping, gene isolation, comparative genomics, analysis of quantitative trait loci and investigations of heterosis.     

An SSR genetic map of Sorghum bicolor (L.) Moench and its comparison to a published genetic map.

Sorghum bicolor (L.) Moench is an important grain and forage crop grown worldwide. We developed a simple sequence repeat (SSR) linkage map for sorghum using 352 publicly available SSR primer pairs and a population of 277 F2 individuals derived from a cross between the Westland A line and PI 550610. A total of 132 SSR loci appeared polymorphic in the mapping population, and 118 SSRs were mapped to 16 linkage groups. These mapped SSR loci were distributed throughout 10 chromosomes of sorghum, and spanned a distance of 997.5 cM. More important, 38 new SSR loci were added to the sorghum genetic map in this study. The mapping result also showed that chromosomes SBI-01, SBI-02, SBI-05, and SBI-06 each had 1 linkage group; the other 6 chromosomes were composed of 2 linkage groups each. Except for 5 closely linked marker flips and 1 locus (Sb6_34), the marker order of this map was collinear to a published sorghum map, and the genetic distances of common marker intervals were similar, with a difference ratio 相似文献   

Genetic mapping of a new set of microsatellite markers in a reference common bean (Phaseolus vulgaris) population BAT93 x Jalo EEP558

The present study describes a new set of 61 polymorphic microsatellite markers for beans and the construction of a genetic map using the BAT93 x Jalo EEP558 (BJ) population for the purpose of developing a reference linkage map for common bean (Phaseolus vulgaris). The main objectives were to integrate new microsatellites on the existing framework map of the BJ population, and to develop the first linkage map for the BJ population based exclusively on microsatellites. Of the total of 264 microsatellites evaluated for polymorphism, 42.8% showed polymorphism between the genitors. An integrated map was created totaling 199 mapped markers in 13 linkage groups, with an observed length of 1358 cM and a mean distance between markers of 7.23 cM. For the map constructed exclusively with microsatellites, 106 markers were placed in 12 groups with a total length of 606.8 cM and average distance of 6.8 cM. Linkage group designation and marker order for BM microsatellites generally agreed with previous mapping, while the new microsatellites were well distributed across the genome, corroborating the utility of the BJ population for a reference map. The extensive use of the microsatellites and the availability of a reference map can help in the development of other genetic maps for common bean through the transfer of information of marker order and linkage, which will allow comparative analysis and map integration, especially for future quantitative trait loci and association mapping studies.     

玉米相对饱和遗传连锁图谱构建与一种新的AFLPs共显性分析方法探讨

利用一个F2作图群体(X178×B73),首先构建了一个含有130个SSRs的玉米连锁框架图,然后用119个AFLPs位点增加图谱密度,得到一个全长1659·3cM,标记间平均间距6·66cM的玉米相对饱和连锁图。同时,对SSRs和AFLPs的一些遗传特性进行了分析,探讨了AFLP标记进行共显性分析的一种新方法。分析表明SSRs和AFLPs分子标记具有多态性和可靠性高等特点,是构建高密度分子标记遗传连锁图的有效技术。加密的玉米遗传连锁图谱为比较基因组研究、数量性状位点(quantitativetraitloci,QTLs)克隆、杂种优势机理研究以及标记辅助选择等提供了技术基础。     

Integrated genome sequence and linkage map of physic nut (Jatropha curcas L.), a biodiesel plant

The family Euphorbiaceae includes some of the most efficient biomass accumulators. Whole genome sequencing and the development of genetic maps of these species are important components in molecular breeding and genetic improvement. Here we report the draft genome of physic nut (Jatropha curcas L.), a biodiesel plant. The assembled genome has a total length of 320.5 Mbp and contains 27 172 putative protein‐coding genes. We established a linkage map containing 1208 markers and anchored the genome assembly (81.7%) to this map to produce 11 pseudochromosomes. After gene family clustering, 15 268 families were identified, of which 13 887 existed in the castor bean genome. Analysis of the genome highlighted specific expansion and contraction of a number of gene families during the evolution of this species, including the ribosome‐inactivating proteins and oil biosynthesis pathway enzymes. The genomic sequence and linkage map provide a valuable resource not only for fundamental and applied research on physic nut but also for evolutionary and comparative genomics analysis, particularly in the Euphorbiaceae.     

A Multi-Population Consensus Genetic Map Reveals Inconsistent Marker Order among Maps Likely Attributed to Structural Variations in the Apple Genome

Genetic maps serve as frameworks for determining the genetic architecture of quantitative traits, assessing structure of a genome, as well as aid in pursuing association mapping and comparative genetic studies. In this study, a dense genetic map was constructed using a high-throughput 1,536 EST-derived SNP GoldenGate genotyping platform and a global consensus map established by combining the new genetic map with four existing reliable genetic maps of apple. The consensus map identified markers with both major and minor conflicts in positioning across all five maps. These major inconsistencies among marker positions were attributed either to structural variations within the apple genome, or among mapping populations, or genotyping technical errors. These also highlighted problems in assembly and anchorage of the reference draft apple genome sequence in regions with known segmental duplications. Markers common across all five apple genetic maps resulted in successful positioning of 2875 markers, consisting of 2033 SNPs and 843 SSRs as well as other specific markers, on the global consensus map. These markers were distributed across all 17 linkage groups, with an average of 169±33 marker per linkage group and with an average distance of 0.70±0.14 cM between markers. The total length of the consensus map was 1991.38 cM with an average length of 117.14±24.43 cM per linkage group. A total of 569 SNPs were mapped onto the genetic map, consisting of 140 recombinant individuals, from our recently developed apple Oligonucleotide pool assays (OPA). The new functional SNPs, along with the dense consensus genetic map, will be useful for high resolution QTL mapping of important traits in apple and for pursuing comparative genetic studies in Rosaceae.     

Regulation of Arabidopsis defense responses against Spodoptera littoralis by CPK-mediated calcium signaling

Background

Genetic markers and linkage mapping are basic prerequisites for marker-assisted selection and map-based cloning. In the case of the key grassland species Lolium spp., numerous mapping populations have been developed and characterised for various traits. Although some genetic linkage maps of these populations have been aligned with each other using publicly available DNA markers, the number of common markers among genetic maps is still low, limiting the ability to compare candidate gene and QTL locations across germplasm.

Results

A set of 204 expressed sequence tag (EST)-derived simple sequence repeat (SSR) markers has been assigned to map positions using eight different ryegrass mapping populations. Marker properties of a subset of 64 EST-SSRs were assessed in six to eight individuals of each mapping population and revealed 83% of the markers to be polymorphic in at least one population and an average number of alleles of 4.88. EST-SSR markers polymorphic in multiple populations served as anchor markers and allowed the construction of the first comprehensive consensus map for ryegrass. The integrated map was complemented with 97 SSRs from previously published linkage maps and finally contained 284 EST-derived and genomic SSR markers. The total map length was 742 centiMorgan (cM), ranging for individual chromosomes from 70 cM of linkage group (LG) 6 to 171 cM of LG 2.

Conclusions

The consensus linkage map for ryegrass based on eight mapping populations and constructed using a large set of publicly available Lolium EST-SSRs mapped for the first time together with previously mapped SSR markers will allow for consolidating existing mapping and QTL information in ryegrass. Map and markers presented here will prove to be an asset in the development for both molecular breeding of ryegrass as well as comparative genetics and genomics within grass species.     

Comparative mapping in Pinus: sugar pine (Pinus lambertiana Dougl.) and loblolly pine (Pinus taeda L.)

The majority of genomic research in conifers has been conducted in the Pinus subgenus Pinus mostly due to the high economic importance of the species within this taxon. Genetic maps have been constructed for several of these pines and comparative mapping analyses have consistently revealed notable synteny. In contrast, little genomic research has been conducted on the Pinus subgenus Strobus, even though these pines have strong ecological relevance. We report a consensus genetic linkage map for sugar pine (Pinus lambertiana Dougl.) constructed with 399 single nucleotide polymorphisms markers derived from annotated genes. The map is 1,231 cM in length and organized into 19 linkage groups. Two of the mapping populations were derived from trees that were segregating for the major gene of resistance (Cr1) to Cronartium ribicola, the fungal pathogen responsible for white pine blister rust. The third mapping population was derived from a full-sib cross segregating for partial resistance to white pine blister rust. In addition, we report the first comparative mapping study between subgenera Strobus and Pinus. Sixty mapped markers were found in common between sugar pine and the loblolly pine reference map with 56 of them (93%) showing collinearity. All 19 linkage groups of the sugar pine consensus map coaligned to the 12 linkage groups of the loblolly pine reference map. The syntenic relationship observed between these two clades of pines provides a foundation for advancing genomic research and genetic resources in subgenus Strobus.