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1.
The demands for increasing global crop production have prompted the development of new approaches relying on molecular marker
technologies to investigate and improve the plant genome. The merits of molecular markers make them valuable tools in a range
of research areas. This review describes novel approaches based on modern molecular marker technologies for characterization
and utilization of genetic variation for wheat improvement. Large-scale genome characterization by DNA-fingerprinting has
revealed no declining trends in the molecular genetic diversity in wheat as a consequence of modern intensive breeding thus
opposing the genetic ‘erosion’ hypothesis. A great number of important major genes and quantitative trait loci have been mapped
with molecular markers. Marker-assisted selection based on a tight linkage between a marker allele and a gene(s) governing
a qualitative or quantitative trait is gaining considerable importance as it facilitates and accelerates cultivar improvement
through precise transfer of chromosome regions carrying the gene of interest. The implementations of molecular markers in
wheat genotyping, mapping and breeding complemented by specific approaches associated with the complex polyploid nature of
common wheat are analyzed and presented. 相似文献
2.
Orphan crops have played a major role in daily diet, health nourishment, economy and livelihood of marginal farmers in under developed and developing world. For various reasons, the majority of these crops including finger millet and tef in cereals; lentil, cowpea and groundnut in legumes; cassava and yam in root crops; have remained neglected and underutilized. With little or no investment these ‘orphan’ crops have lagged far behind in developing genomic resources and are deprived of the application of advanced molecular breeding approaches for their rapid improvement. Single nucleotide polymorphisms, multiple nucleotide polymorphisms, insertions/deletions (indels) and size polymorphisms are important tools for developing rich molecular marker resources. Cataloguing and use of intron based polymorphism have also been demonstrated for applications in molecular breeding. Currently the process of predicting putative introns and designing flanking primers for their amplification requires multiple computer programs and a high level of human intervention. We automated this process by developing intron mapping pipeline (IMP) which allows the generation of large primer sets with minimal human intervention and greater efficiency. Since IMP can take advantage of the highly conserved nature of the introns flanking sequences across a wide range of species, any available model plant genome can be used to predict intron boundaries in related orphan crop species. IMP combined with high resolution melt analysis demonstrated potential for high throughput polymorphism discovery, validation and molecular marker development platform which can generate genomic resources rapidly in orphan species. 相似文献
3.
Haile Desmae Pasupuleti Janila Patrick Okori Manish K. Pandey Babu N. Motagi Emmanuel Monyo Omari Mponda David Okello Dramane Sako Candidus Echeckwu Richard Oteng‐Frimpong Amos Miningou Chris Ojiewo Rajeev K. Varshney 《Plant Breeding》2019,138(4):425-444
Groundnut is an important food and oil crop in the semiarid tropics, contributing to household food consumption and cash income. In Asia and Africa, yields are low attributed to various production constraints. This review paper highlights advances in genetics, genomics and breeding to improve the productivity of groundnut. Genetic studies concerning inheritance, genetic variability and heritability, combining ability and trait correlations have provided a better understanding of the crop's genetics to develop appropriate breeding strategies for target traits. Several improved lines and sources of variability have been identified or developed for various economically important traits through conventional breeding. Significant advances have also been made in groundnut genomics including genome sequencing, marker development and genetic and trait mapping. These advances have led to a better understanding of the groundnut genome, discovery of genes/variants for traits of interest and integration of marker‐assisted breeding for selected traits. The integration of genomic tools into the breeding process accompanied with increased precision of yield trialing and phenotyping will increase the efficiency and enhance the genetic gain for release of improved groundnut varieties. 相似文献
4.
To meet the challenges of climate change, exploring natural diversity in the existing plant genetic resource pool as well as creation of new mutants through chemical mutagenesis and molecular biology is needed for developing climate‐resilient elite genotypes. Ever‐increasing area under existing abiotic stresses as well as emerging abiotic stress factors and their combinations have further added to the problems of the current crop improvement programmes. However, with the advancement in modern techniques such as next‐generation sequencing technologies, it is now possible to generate on a whole‐genome scale, genomic resources for crop species at a much faster pace with considerably less efforts and money. The genomic resources thus generated will be useful for various plant breeding applications such as marker‐assisted breeding for gene introgression, mapping QTLs or identifying new or rare alleles associated with a particular trait. In this article, we discuss various aspects of generation of genomic resources and their utilization for developing abiotic stress‐tolerant crops to ensure sustainable agricultural production and food security in the backdrop of rapid climate change. 相似文献
5.
Molecular markers in Brassica oilseed breeding: current status and future possibilities 总被引：6，自引：0，他引：6
As PCR techniques have developed over the last 15 years, a wealth of new DNA marker technologies have arisen which have enabled the generation of high‐density molecular maps for all the major Brassica crop species. Molecular markers have also been heavily used in analyses of genetic diversity in Brassica crops. The majority of the work utilizing molecular markers in Brassica oilseed breeding has to date been based on genetic mapping using various DNA marker systems in segregating populations generated for specific investigations of particular traits of interest. For numerous qualitative traits, traditional mapping approaches have led to the development of marker‐assisted selection strategies in oilseed Brassica breeding, and in some cases to map‐based cloning of the responsible genes. For quantitative traits, however, it has become apparent that traditional mapping of quantitative trait loci (QTL) is often not sufficient to develop effective markers for trait introgression or for identification of the genes responsible. In this case, allele‐trait association studies in non‐structured genetic populations represent an interesting new approach, provided the degree of gametic phase disequilibrium between the QTL and the marker loci is sufficient. Because Brassica species represent the closest crop plant relatives to the model plant Arabidopsis thaliana, significant progress will be achieved in the coming years through integration of candidate gene approaches in crop brassicas, using the detailed information now available for the Arabidopsis genome. Integration of information from the model plant with the increasing supply of data from physical mapping and sequencing of the diploid Brassica genomes will undoubtedly give great insight into the genetics underlying both simple and complex traits in oilseed rape. This review describes the current use of available genetic marker technologies in oilseed rape breeding and provides an outlook for use of new technologies, including single‐nucleotide polymorphism markers, candidate gene approaches and allele‐trait association studies. 相似文献
6.
In recent years, molecular markers have been utilized for a variety of applications including examination of genetic relationships
between individuals, mapping of useful genes, construction of linkage maps, marker assisted selections and backcrosses, population
genetics and phylogenetic studies. Among the available molecular markers, microsatellites or simple sequence repeats (SSRs)
which are tandem repeats of one to six nucleotide long DNA motifs, have gained considerable importance in plant genetics and
breeding owing to many desirable genetic attributes including hypervariability, multiallelic nature, codominant inheritance,
reproducibility, relative abundance, extensive genome coverage including organellar genomes, chromosome specific location
and amenability to automation and high throughput genotyping. High degree of allelic variation revealed by microsatellite
markers results from variation in number of repeat-motifs at a locus caused by replication slippage and/or unequal crossing-over
during meiosis. In spite of limited understanding of the functions of the SSR motifs within the plant genes, SSRs are being
widely utilized in plant genome analysis. Microsatellites can be developed directly from genomic DNA libraries or from libraries
enriched for specific microsatellites. Alternatively, microsatellites can also be found by searching public databases such
as GenBank and EMBL or through cross-species transferability. At present, EST databases are an important source of candidate
genes, as these can generate markers directly associated with a trait of interest and may be transferable in close relative
genera. A large number of SSR based techniques have been developed and a quantum of literature has accumulated regarding the
applicability of SSRs in plant genetics and genomics. In this review we discuss the recent developments (last 4–5 years) made
in plant genetics using SSR markers. 相似文献
7.
Straighthead is a physiological disorder in rice (Oryza sativa L.) resulting in sterile florets, poorly developed panicles and yield loss. Because of its sporadic nature and unidentified causes for the disorder, molecular marker assisted selection is essential for resistance improvement in breeding programmes. To take advantage of recent advances in gene‐mapping technology, we executed a genome‐wide association mapping to identify genetic regions associated with straighthead disorder using 547 accessions of germplasm from the USDA rice core collection. Straighthead was evaluated in arsenic treated soil and genotyping was conducted with 75 molecular markers covering the entire rice genome about every 25 cM. A mixed‐linear model approach combining the principal component assignments with kinship estimates proved to be particularly promising for association mapping. The extent of linkage disequilibrium was described among the markers. Six markers were found to be significantly associated with straighthead, explaining 35% of the total phenotypic variation. However, only two SSR markers, RM413 and RM277 on chromosome 5 and 12, respectively, have a significant association with low rating indicating straighthead resistance. Confirmation of the marker‐straighthead association using segregating populations is necessary before marker‐assisted selection can be applied. 相似文献
8.
简要介绍了5种传统的、最常用的DNA分子标记(RFLP、RAPD、AFLP、SSR和SNP)的技术原理及它们的优缺点,也总结了TRAP这种新产生的分子标记的技术原理、优点及应用前景.综述了这几类分子标记在花生种质进化、遗传多样性分析、分子图谱构建及抗虫、抗病等方面的研究.利用SSR和RAPD标记能够发现野生种和栽培种多态性进而实现分子标记对花生的遗传多样性分析,可以将许多花生品种分为不同的品种群,能够对花生进行种质进化研究.RFLP和AFLP技术利于花生图谱构建,利用DNA中特定的限制性酶切位点上碱基对的改变及酶切位点之间的分子重排,可以发现花生品种间的DNA许多多态性位点,进而绘制分子标记图谱.AFLP技术在花生青枯菌和花生抗黄曲霉的研究方面有很大进展.RAID技术在花生根瘤菌、花生线虫病等方面已有显著进展.最后对分子标记在花生育种中的应用前景进行了简单展望. 相似文献
9.
10.
Jiffinvir S. Khosa John McCallum Ajmer S. Dhatt Richard C. Macknight 《Plant Breeding》2016,135(1):9-20
Bulb onion (Allium cepa L.) is an ancient crop that is thought to have originated in Central Asia and has been cultivated for over 5000 years. Classical genetic and plant breeding approaches have been used to improve onion yield, quality, and resistance against biotic and abiotic stresses. However, its biennial life cycle, cross‐pollinated nature and high inbreeding depression have proved challenging for the characterization and breeding of improved traits. New technologies, notably next‐generation sequencing, are providing researchers with the genomic resources and approaches to overcome these challenges. Using these genomic technologies, molecular markers are being rapidly developed and utilized for germplasm analysis and mapping in onion. These new tools and knowledge are allowing the integration of molecular and conventional breeding to speed up onion improvement programmes. In this review, we outline recent progress in onion genomics and molecular genetics and prospects for enhancing onion yield and quality in the future. 相似文献
11.
12.
黄颡鱼DNA分子标记的研究进展 总被引：1，自引：0，他引：1
为了深入了解黄颡鱼在多种DNA分子标记中的应用研究。详细阐述黄颡鱼多个类型的DNA分子标记的原理,优缺点及其研究进展,对其应用前景和存在的问题进行了综述,并对黄颡鱼的DNA分子标记研究提出了建设性意见,为黄颡鱼种质资源的保护与合理开发提供参考资料。 相似文献
13.
Next-generation sequencing technologies have enabled the rapid generation of high-resolution genetic maps to enable the identification of genomic regions associated with traits of interest. In certain cases these regions of interest need to be narrowed down via fine mapping to increase resolution to the level of the individual gene. In those cases, there is a choice of genotyping options, whereby cost, time, and information content need to be considered. We developed detailed, customizable models to compare the cost of genotyping by sequencing and allele-specific PCR for fine-mapping genomic regions of interest. The models were validated experimentally with data from a fine-mapping experiment designed to identify candidate genes within a 3.2-Mb disease resistance locus in the cereal crop sorghum (Sorghum bicolor (L.). Moench), which has a sequenced genome. The size of the mapping population, genetic diversity of the parental lines, choice of reagents, and labor cost were shown to influence the overall cost of the two methods, and, consequently, which method would be most cost-effective for a given experiment. The model can be easily customized to reflect experiments with different species, genetic populations, experimental and personnel costs to determine the most cost-effective procedure for a new positional cloning project. 相似文献
14.
新一代测序技术及其对水稻分子设计育种的影响 总被引：6，自引：0，他引：6
本文概述了以边合成（或连接）边测序为特征的新一代测序技术的基本原理以及现有的Roche（454）GSFLXsequencer、Illumina genome analyzer（Solexa）、Applied Biosystems SOLiDsequencer、HeliScope Sequencer等4种新一代测序平台的发展历史、测序流程、优缺点和测序成本等,并展望了新技术的发展可能对以水稻为代表的农作物大规模分子设计育种产生的影响。本文还提出通过对水稻核心种质育种材料体系的全基因组测序,开发功能性分子标记和特异基因芯片,缩短将基础研究成果应用于实际育种生产的时间,为真正进入分子设计育种时代奠定基础。 相似文献
15.
Comparison among available marker systems for cereal introgression breeding: A practical perspective
Pilar Hernandez 《Euphytica》2005,146(1-2):95-100
Summary There is an increasing amount of public sequence information for the main cultivated cereals, such as wheat and barley. It
is not foreseeable that comparable efforts or resources could be devoted to related wild species. However, wild species are
interesting sources of genetic variation through introgression breeding. Comparative genomics can be a helpful approach to
make use of the available genomic resources. In this context, the potential of the wild barley species Hordeum chilense has been explored in recent years. It exhibits great levels of polymorphism and high crossability with different cereal genera.
In addition, interesting biotic and abiotic stress resistance genes, and important quality traits like carotene content and
seed storage protein variability shown in the species are also expressed in wheat backgrounds, and are the basis of a breeding
program. Different approaches have been undertaken for tagging H. chilense genomic regions in a wheat background. The search for the most suitable DNA marker system started with the development of
RAPD and SCAR markers due to a lack of sequence information from the wild species. Transferability of markers from wheat and
barley (like STSs or SSRs) have also been useful approximations. More recently, SNP development is being accomplished for
the species. In this work, the situation and prospects with the available molecular tools are considered from a practical
point of view. 相似文献
16.
甜瓜是重要的葫芦科蔬菜作物之一,其遗传育种学广受研究者的关注。高密度分子遗传图谱有助于提高甜瓜的育种水平,加快育种进程。自1996年第一张甜瓜分子遗传图谱报道后,AFLP等分子标记逐步被应用于甜瓜分子遗传图谱的构建及基因定位。近年来,基因组测序技术发展迅速,全基因组重测序、简化基因组测序、转录组测序等技术逐渐被应用于构建覆盖全基因组的、更加饱和的甜瓜遗传连锁图谱。本研究着重对甜瓜分子遗传图谱、重要农艺性状基因定位研究进展进行了综述,以期为甜瓜生物学研究及分子改良提供理论参考。 相似文献
17.
为了探究毛细管与聚丙烯酰胺电泳方法的适用情况，比较其优缺点。本研究以8个甜菜栽培种资源为材料，选择8个SSR位点，分别使用聚丙烯酰胺凝胶电泳银染检测和毛细管电泳荧光检测每个位点的多态性，并对这两种方法的检测结果进行了比较。毛细管电泳荧光标记法可以准确的知道DNA片段的分子大小；PAGE电泳只能用肉眼与Marker比较估测得出大致分子量，不能得出准确分子量。8对引物两种检测方法的匹配比率分别是75%、87.5%、50%、75%、25%、100%、37.5%、50%。研究结果证明，两种检测平台数据整合存在较大差异。检测结果与引物是否是单拷贝、引物多态性，稳定性等因素有直接关系。测序检验结果表明，样品较少时利用PAGE电泳的方法来检测SSR位点的多态性，既能节省成本又能节省时间，还能保证检测结果的准确性。 相似文献
18.
中国玉米分子标记技术研究进展 总被引：6，自引：2，他引：6
概述了近年来分子标记技术在中国玉米遗传多样性、杂种优势及杂种产量的预测、目标基因和QTL定位、DNA指纹图谱构建和杂交种子纯度鉴定等研究方面的应用。认为分子标记技术在以下方面将具有广阔的前景:(1)在玉米特用种质资源的发现、鉴定、分类整理和开发利用上,应用分子标记技术,能进一步挖掘与玉米高产、优质、高抗有关的基因性状,从而进行基因的定位和标记,提高玉米育种的效率。(2)运用该技术对玉米抗病、抗虫、抗涝、抗旱等抗逆性基因进行精确定位,为这些抗逆基因的克隆、转化及利用打下良好基础,为分子标记辅助选择育种提供了便利,有利于加快育种进程。(3)随着分子标记技术的进一步完善与发展,以及玉米DNA指纹计算机应用软件的开发,其检测技术将逐步程序化、简单化和自动化,应用分子标记技术可以经济、迅速、准确的鉴定和检测玉米自交系或杂交种的纯度及真伪,为品种保护和开发提供可靠的依据。 相似文献
19.
概述了近年来分子标记技术在中国玉米遗传多样性、杂种优势及杂种产量的预测、目标基因和QTL定位、DNA指纹图谱构建和杂交种子纯度鉴定等研究方面的应用。认为分子标记技术在以下方面将具有广阔的前景：(1)在玉米特用种质资源的发现、鉴定、分类整理和开发利用上,应用分子标记技术,能进一步挖掘与玉米高产、优质、高抗有关的基因性状,从而进行基因的定位和标记,提高玉米育种的效率。(2)运用该技术对玉米抗病、抗虫、抗涝、抗旱等抗逆性基因进行精确定位,为这些抗逆基因的克隆、转化及利用打下良好基础,为分子标记辅助选择育种提供了便利,有利于加快育种进程。(3)随着分子标记技术的进一步完善与发展,以及玉米DNA指纹计算机应用软件的开发,其检测技术将逐步程序化、简单化和自动化,应用分子标记技术可以经济、迅速、准确的鉴定和检测玉米自交系或杂交种的纯度及真伪,为品种保护和开发提供可靠的依据。 相似文献
20.
Journal of Crop Science and Biotechnology - The recent advancement of bioinformatics tools and next-generation sequencing (NGS) has created enormous opportunities for a thorough understanding of... 相似文献