共查询到20条相似文献，搜索用时 78 毫秒
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Crop salt tolerance (ST) is a complex trait affected by numerous genetic and non‐genetic factors, and its improvement via conventional breeding has been slow. Recent advancements in biotechnology have led to the development of more efficient selection tools to substitute phenotype‐based selection systems. Molecular markers associated with genes or quantitative trait loci (QTLs) affecting important traits are identified, which could be used as indirect selection criteria to improve breeding efficiency via marker‐assisted selection (MAS). While the use of MAS for manipulating simple traits has been streamlined in many plant breeding programmes, MAS for improving complex traits seems to be at infancy stage. Numerous QTLs have been reported for ST in different crop species; however, few commercial cultivars or breeding lines with improved ST have been developed via MAS. We review genes and QTLs identified with positive effects on ST in different plant species and discuss the prospects for developing crop ST via MAS. With the current advances in marker technology and a better handling of genotype by environment interaction effects, the utility of MAS for breeding for ST will gain momentum. 相似文献
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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
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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
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Molecular markers: It’s application in crop improvement 总被引：1，自引：0，他引：1
Mahipal Singh Kesawat Basanta Das Kumar 《Journal of Crop Science and Biotechnology》2009,12(4):169-181
Over the past few decades, plant genomics research has been studied extensively bringing about a revolution in the field of
plant biotechnology. Molecular markers, useful for plant genome analysis, have now become an important tool in crop improvement.
The development and use of molecular markers for the detection and exploitation of DNA polymorphism is one of the most significant
developments in the field of molecular genetics. The presence of various types of molecular markers, and differences in their
principles, methodologies and applications require careful consideration in choosing one or more of such methods. No molecular
markers are available yet that fulfill all requirements needed by researchers. In this article we attempt to review most of
the available DNA markers that can be routinely employed in various aspects of plant genome analysis such as characterization
of genetic variability, genome fingerprinting, genome mapping, gene localization, analysis of genome evolution, population
genetics, taxonomy, plant breeding, and diagnostics. The emerging patterns make up a unique feature of the analyzed individual
and are currently considered to be the ultimate tool for biological individualization. 相似文献
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Ousmane Boukar Nouhoun Belko Siva Chamarthi Abou Togola Joseph Batieno Emmanuel Owusu Mohammed Haruna Sory Diallo Muhammed Lawan Umar Olusoji Olufajo Christian Fatokun 《Plant Breeding》2019,138(4):415-424
Cowpea, Vigna unguiculata (L.), is an important grain legume grown in the tropics where it constitutes a valuable source of protein in the diets of millions of people. Some abiotic and biotic stresses adversely affect its productivity. A review of the genetics, genomics and breeding of cowpea is presented in this article. Cowpea breeding programmes have studied intensively qualitative and quantitative genetics of the crop to better enhance its improvement. A number of initiatives including Tropical Legumes projects have contributed to the development of cowpea genomic resources. Recent progress in the development of consensus genetic map containing 37,372 SNPs mapped to 3,280 bins will strengthen cowpea trait discovery pipeline. Several informative markers associated with quantitative trait loci (QTL) related to desirable attributes of cowpea were generated. Cowpea genetic improvement activities aim at the development of drought tolerant, phosphorus use efficient, bacterial blight and virus resistant lines through exploiting available genetic resources as well as deployment of modern breeding tools that will enhance genetic gain when grown by sub‐Saharan Africa farmers. 相似文献
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Research Progress on the Mendelian Genetic Analysis and Molecular Mapping of Morphological Qualitative Traits in Cotton 总被引：2，自引：2，他引：0
Genetic analysis and molecular mapping of qualitative traits are important tools in cotton breeding. Research on cotton qualitative traits has been reported since the early 1900s. Rapid advances in cotton genomics and molecular mapping over the past several years have facilitated the mapping and cloning of important qualitative trait genes in cotton. Although most of the 101 genes and alleles related to cotton morphological qualitative traits have not been mapped to linkage groups or chromosomes, several genes have been cloned and identified via map-based cloning. This paper describes research progress on the genetic and linkage analysis, molecular mapping, and candidate gene cloning of eight major types of morphological qualitative traits: plant color, leaf color, leaf shape, bract, flower, nectary, gland, and fiber characteristics. The presented information lays a foundation for studying the molecular basis of qualitative traits, favorable gene-based transfer, and gene pyramiding in cotton. 相似文献
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Teresa Millan Heather J. Clarke Kadambot H. M. Siddique Hutokshi K. Buhariwalla Pooran M. Gaur Jagdish Kumar Juan Gil Guenter Kahl Peter Winter 《Euphytica》2006,147(1-2):81-103
Summary Chickpea is a cool season grain legume of exceptionally high nutritive value and most versatile food use. It is mostly grown
under rain fed conditions in arid and semi-arid areas around the world. Despite growing demand and high yield potential, chickpea
yield is unstable and productivity is stagnant at unacceptably low levels. Major yield increases could be achieved by development
and use of cultivars that resist/tolerate abiotic and biotic stresses. In recent years the wide use of early maturing cultivars
that escape drought stress led to significant increases in chickpea productivity. In the Mediterranean region, yield could
be increased by shifting the sowing date from spring to winter. However, this is hampered by the sensitivity of the crop to
low temperatures and the fungal pathogen Ascochyta rabiei. Drought, pod borer (Helicoverpa spp.) and the fungus Fusarium oxysporum additionally reduce harvests there and in other parts of the world. Tolerance to rising salinity will be a future advantage
in many regions. Therefore, chickpea breeding focuses on increasing yield by pyramiding genes for resistance/tolerance to
the fungi, to pod borer, salinity, cold and drought into elite germplasm. Progress in breeding necessitates a better understanding
of the genetics underlying these traits. Marker-assisted selection (MAS) would allow a better targeting of the desired genes.
Genetic mapping in chickpea, for a long time hampered by the little variability in chickpea’s genome, is today facilitated
by highly polymorphic, co-dominant microsatellite-based markers. Their application for the genetic mapping of traits led to
inter-laboratory comparable maps. This paper reviews the current situation of chickpea genome mapping, tagging of genes for
ascochyta blight, fusarium wilt resistance and other traits, and requirements for MAS. Conventional breeding strategies to
tolerate/avoid drought and chilling effects at flowering time, essential for changing from spring to winter sowing, are described.
Recent approaches and future prospects for functional genomics of chickpea are discussed. 相似文献
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作物根系与水肥利用密切相关,发掘根系性状相关遗传位点或候选基因,对于培育适宜特定土壤环境的小麦新品种具有重要意义。为系统了解低氮磷供应、盐碱、干旱等非生物胁迫对根系的影响,以及小麦根系性状遗传定位进展,本研究对近几十年相关文献进行了调研。发现尽管目前对小麦根系性状遗传解析工作已有较多报道,但许多根系性状QTL区间在不同研究间难以吻合,限制了分子标记开发和候选基因的发掘。随着高密度SNP芯片的开发及全基因组重测序技术的发展,今后整合"表型组"、"基因组"、"转录组"和"代谢组"对特定环境条件下小麦根系性状进行解析,可快速、高效地发掘特定环境条件下的优异等位变异和候选基因。本研究对于了解非生物胁迫条件小麦根系性状的遗传学基础具有参考价值。 相似文献
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Genetic impacts under selective breeding of agricultural crops have been frequently investigated with molecular tools, but
inadequate attention has been paid to assess genetic changes under long-term genetic improvement of plant traits. Here we
analyzed allelic changes with respect to wheat trait improvement in 78 Canadian hard red spring wheat cultivars released from
1845 to 2004 and screened with 370 mapped SSR markers. The improvements in quality, maturity, yield, disease, stem rust, leaf
rust, sawfly resistance, and agronomy were considered. A total of 154 (out of 370) loci with significant allelic changes across
21 chromosomes were detected in the 78 wheat cultivars separated into improved versus non-improved groups for eight traits.
The number of significant loci for improving a trait ranged from four for quality to 68 for yield and averaged 35. Many more
loci with significant allelic reduction for improving a trait were detected than those with significant allelic increase.
Selection for early maturity introduced more alleles, but improving the other traits purged more alleles. Significantly lower
numbers of unique alleles were found in the cultivars with improved traits. The distributions of unique allele counts also
varied greatly across the 21 chromosomes with respect to trait improvement. Significant SSR variation between two cultivar
groups was observed for improvement in seven traits, but not in stem rust. The proportional SSR variation residing between
two groups ranged from 0.014 to 0.118. The proportional SSR variations within the improved cultivar groups consistently were
much lower than those within the non-improved groups. These findings clearly demonstrate the association between allelic changes
and wheat trait improvements and are useful for understanding the genetic modification of the wheat genome by long-term wheat
breeding. 相似文献
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Cotton (Gossypium spp.) is the leading fiber crop,and an important source of the important edible oil and protein meals in the world.Complex genetics and strong environmental effects hinder much progress in seed quality trait breeding in cotton.The use of molecular markers will improve our understanding of the genetic factors conferring seed quality traits,and it is expected to assist in selection of superior genotypes. 相似文献
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B. B. Dholakia J. S. S. Ammiraju H. Singh M. D. Lagu M. S. Röder V. S. Rao H. S. Dhaliwal P. K. Ranjekar V. S. Gupta W. E. Weber 《Plant Breeding》2003,122(5):392-395
The economic value of wheat grain is determined by the kernel morphology which is an important parameter for manufacturing different food products requiring specific grain characteristics. Although kernel size and shape have emerged as important breeding objectives, not much information is available about the number or location of associated gene(s)/quantitative trait loci. In the present study, a recombinant inbred line population of 106 plants (F7) was phenotyped for four traits, namely kernel length, width, weight and factor form density (FFD) and genotyped with different polymerase chain reaction‐based markers. Transgressive segregants were observed for all the traits and genetic correlation studies showed positive correlations between the majority of the traits. The number of markers associated with each trait ranged from two to nine and the phenotypic contribution by an individual marker ranged from 3.3 to 16.6%. Many of the markers showed linkage to more than one trait. Strategies for improving the wheat grain quality traits and the utility of such markers in marker‐assisted selection (MAS) efforts are discussed. 相似文献
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甜瓜基因组学研究进展 总被引：7，自引：0，他引：7
甜瓜是一种世界性的园艺作物.随着现代生物技术的迅速发展,甜瓜基因组学研究越来越深入,国际葫芦科基因组计划也已经筹备完成即将启动.目前已构建有14张甜瓜遗传图谱,多个重要性状的分子标记及数量性状位点已找到并定位在图中,并开始在葫芦科作物之间进行比较基因组图谱方面的研究.已克隆出枯萎病抗性基因Fom-2,其它农艺性状基因的克隆工作也在陆续开展.本文在甜瓜遗传连锁图谱的构建、重要性状分子标记及OTL定位、比较基因组学及基因克隆等方面分别对其研究进展进行了探讨,以期为我国的甜瓜基因组学研究提供有益的参考. 相似文献
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N. A. Alimi M. C. A. M. Bink J. A. Dieleman M. Nicolaï M. Wubs E. Heuvelink J. Magan R. E. Voorrips J. Jansen P. C. Rodrigues G. W. A. M. van der Heijden A. Vercauteren M. Vuylsteke Y. Song C. Glasbey A. Barocsi V. Lefebvre A. Palloix F. A. van Eeuwijk 《Euphytica》2013,190(2):181-201
An interesting strategy for improvement of a complex trait dissects the complex trait in a number of physiological component traits, with the latter having hopefully a simple genetic basis. The complex trait is then improved via improvement of its component traits. As first part of such a strategy to improve yield in pepper, we present genetic and QTL analyses for four pepper experiments. Sixteen traits were analysed for a population of 149 recombinant inbred lines, obtained from a cross between the large-fruited pepper cultivar ‘Yolo Wonder’ (YW) and the small fruited pepper ‘Criollo de Morelos 334’ (CM334). The marker data consisted of 493 markers assembled into 17 linkage groups covering 1,775 cM. The trait distributions were unimodal, although sometimes skewed. Many traits displayed heterosis and transgression. Heritabilities were high (mean 0.86, with a range between 0.43 and 0.96). A multiple QTL mapping approach per trait and environment yielded 24 QTLs. The average numbers of QTLs per trait was two, ranging between zero and six. The total explained trait variance by QTLs varied between 9 and 61 %. QTL effects differed quantitatively between environments, but not qualitatively. For stem-related traits, the trait-increasing QTL alleles came from parent CM334, while for leaf and fruit related traits the increasing QTL alleles came from parent YW. The QTLs on linkage groups 1b, 2, 3a, 4, 6 and 12 showed pleiotropic effects with patterns that were consistent with the genetic correlations. These results contribute to a better understanding of the genetics of yield-related physiological traits in pepper and represent a first step in the improvement of the target trait yield. 相似文献
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植物矮生性状的分子遗传研究进展 总被引：15，自引：0，他引：15
近年来，随着分子生物学和基因组学的飞速发展，对作物高产性状，高产机理及其相关基因的研究愈加深入，应用基因工程技术对作物进行遗传改良已成为提高作物产量的有效途径，培育理想株型已成为作物育种的重要目标。株高是高等作物的重要农艺性状之一，植株过高容易引起倒伏而减产，而矮生植株抗倒能力强，高产，因而矮化育种对培育理想株型十分重要，矮生基因的发掘研究和利用也越来越受到重视。本文综述了目前高等作物矮生性的分子遗传研究进展，特别是对水稻、小麦、玉米、黄瓜、西瓜和番茄等主要作物矮生性状的遗传特点、分子标记、矮生基因的克隆等方面的研究进展做了较为详细的总结和评价，分析了激素对高等植物矮生突变体的调控，提出了高等植物矮生资源的利用和矮化育种中存在的问题，并探讨了高等植物矮生性状分子遗传学研究和分子育种的发展趋势。 相似文献
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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
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大豆分子育种现状、挑战与展望 总被引：1，自引：1，他引：0
近年来,大豆育种技术取得了重要进展,育种理论和技术也发生了重大变革。通过多种技术的集成与整合,加速了优质大豆培育进程,以分子标记辅助育种、转基因育种等技术逐渐成为大豆遗传改良的重要手段。本研究综述了大豆分子标记辅助育种、大豆转基因及分子设计育种的研究进展,分析了中国大豆分子育种现状和挑战,认为中国大豆分子育种存在优异基因资源匮乏,大豆分子育种技术方法相对落后,分子育种培育的突破性品种过少等问题,提出了未来要加强重要经济性状形成的遗传和分子基础研究,要重视加强多种模型的开发等几点建议。 相似文献
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构建数量性状基因图谱的统计方法 总被引：11，自引：1，他引：11
随着分子生物学研究的迅速发展和人类基因组统计的深入，数量遗传学在数量性状基因（ＱＴＬ）的定位方面正在经历着一场深刻的变化。人类和动、植物基因组计划的早期成果之一，就是建立人类以及实验、家养动物和栽培植物的遗传连锁图、利用这些连锁图，可以对许多ＱＴＬ进行单个分离测定和定位。许多复杂疾病和具有重要农 生物学意义的性状都属于数量性状。在ＱＴＬ定位的研究中，统计分析起着很重要的作用。近年来有许多新的统计方 相似文献