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标记辅助选择改良数量性状的研究进展 Advances on Marker-Assisted Selection in the Improvement of Quantitative Traits
刘鹏渊,朱军LIU Peng-yuan,ZHU Jun
遗传 , 2001,
Abstract: 本文系统地介绍了近年来有关标记辅助选择改良数量性状的研究进展,主要包括标记辅助回交、指数选择与最佳线性无偏预测的理论和应用研究概况.理论与计算机模拟表明标记辅助选择比常规表型选择更有效,但在实际育种中并不理想.同时本文还就当前标记辅助选择存在的问题和前景进行了讨论。 Abstract:Recent advances on marker-assisted selection (MAS) in the improvement of quantitative traits are reviewed.These include theoretical researches and applications of marker-assisted backcrossing,index selection,and best linear unbiased prediction (BLUP) in animal and plant breeding.Theoretical and simulation studies show that marker-assisted selection can substantially increase the efficiency of selection in comparison to phenotypic selection,but is not yet a proven technology.Problems and prospects in MAS are also discussed.
Comparison of potentials between genotype-based selection and genotypic value-based selection of quantitative traits
Weiren Wu,Yuanchang Zhou,Weiming Li
Chinese Science Bulletin , 2002, DOI: 10.1360/02tb9451
Abstract: According to the difference of selection criteria, methods of marker-assisted selection (MAS) of quantitative traits can be divided into genotype-based selection (GS) and genotypic value-based selection (GVS). By means of computer simulation, potentials of the two methods were compared. Results showed that the two methods had similar basic laws and their efficiencies were not significantly different except that GS behaved better in the case where the number of QTLs was large and QTL effects were equal. From the application point of view, combination of GS and GVS should be the development direction of MAS research in the future.
Genomic value prediction for quantitative traits under the epistatic model
Zhiqiu Hu, Yongguang Li, Xiaohui Song, Yingpeng Han, Xiaodong Cai, Shizhong Xu, Wenbin Li
BMC Genetics , 2011, DOI: 10.1186/1471-2156-12-15
Abstract: In this study, we created 126 recombinant inbred lines of soybean and genotyped 80 makers across the genome. We applied the genome selection technique to predict the genomic value of somatic embryo number (a quantitative trait) for each line. Cross validation analysis showed that the squared correlation coefficient between the observed and predicted embryo numbers was 0.33 when only main (additive) effects were used for prediction. When the interaction (epistatic) effects were also included in the model, the squared correlation coefficient reached 0.78.This study provided an excellent example for the application of genome selection to plant breeding.Genome selection refers to a method for genomic value prediction using markers of the entire genome [1,2]. It is effective for genetic improvement of quantitative traits that are controlled by multiple quantitative trait loci (QTL). Some traits may be controlled by only a few QTL and marker assisted selection using only the few detected QTL can be effective. However, most quantitative traits are determined by multiple QTL and their interactions. Marker assisted selection using only a few detected loci may not be efficient for these traits. Using all QTL collectively to predict the breeding values of individual plants can outperform the traditional marker assisted selection [3,4]. However, there might be some trade off between the numbers of QTL included in the model and the efficiency of prediction. Cross validation can help us determine the optimal number of QTL included in the model to maximize the efficiency of genome selection.The importance of epistasis in genetic determination may vary across different species. In agricultural crops, most quantitative traits in barley do not have a strong basis of epistatic effects [5]. However, epistasis has been shown to be important in QTL studies in rice [6-8]. Dudley and Johnson [9] found that epistatic effects are more important than additive effects in determination of oil,
Detection of quantitative trait loci for physical traits of cashew apple  [PDF]
Francisco Herberth Costa dos Santos,José Jaime Vasconcelos Cavalcanti,Fanuel Pereira da Silva
Crop Breeding and Applied Biotechnology , 2010,
Abstract: The identification of loci controlling quantitative traits (QTL) and marker-assisted selection have attractedgreat interest in breeding programs for fruit quality. This study aimed to identify QTLs related to the quality of cashew apple.Physical analysis were carried out in cashew fruits of 66 F1 plants from the cross of CCP 1001 x CP 96. Seven traits relatedto color, size and weight of the cashew apple were tested for QTLs. Candidate QTLs were identified by the methods of intervalmapping and multiple QTL mapping. Thirty QTLs associated with cashew quality were identified. The lowest number of QTL(two) was detected for the trait red intensity, and the highest (seven) for cashew apple weight. The QTLs explained between3.15% and 21.33% of the total phenotypic variation and are being evaluated for future use in marker-assisted selection.
Marker Assisted Selection for Leaf Blast Disease resistance and other yield traits in rice (Oryza sativa L.) using RAPD Markers
Immanuel Selvaraj. C, , Pothiraj Nagarajan, K. Thiyagarajan, M Bharathi, and R Rabindran
Electronic Journal of Plant Breeding , 2011,
Abstract: A segregating population of 220 F2 individuals was developed by raising the selfed F1 seeds of a single hybrid plant, White Ponnix Moroberekan. Two hundred and twenty F3 families were phenotyped for blast resistance under artificial condition. Bulksegregantanalysis resulted in the identification of 12 leaf blast resistant phenotype specific RAPD markers. Mapping survey wasdone with seven RAPD primers which co-segregated in BSA. Twelve RAPD markers were scored in the F2 mapping population.Out of 12 marker loci, 11 marker loci (91.97 per cent) fitted into the expected segregation ratio of 3:1 based on χ2- test at 0.05per cent probability value. One way ANOVA was performed to identify the marker phenotype association and this resulted in theidentification of seven RAPD markers linked to three traits viz., leaf blast resistance (OPBB 5258, OPBB 5194, OPAL 16940 andOPBD 12680), five markers for GPT and one marker for grain yield per plant.
Efficiency of genomic selection using Bayesian multi-marker models for traits selected to reflect a wide range of heritabilities and frequencies of detected quantitative traits loci in mice
Dagmar NRG Kapell, Daniel Sorensen, Guosheng Su, Luc LG Janss, Cheryl J Ashworth, Rainer Roehe
BMC Genetics , 2012, DOI: 10.1186/1471-2156-13-42
Abstract: Genomic selection showed a high predictive ability (PA) in comparison to traditional polygenic selection, especially for traits of moderate heritability and when cross-validation was between families. This occurred although the proportion of genomic variance of traits using genomic models was 22 to 33% smaller than using polygenic models. Using a 2.5% mixture genomic model, the proportion of genomic variance was 79% smaller relative to the polygenic model. Although the proportion of variance explained by the markers was reduced further when a smaller number of SNPs was assumed to have a substantial effect on the trait, PA of genomic selection for most traits was little affected. These low mixture percentages resulted in improved estimates of single SNP effects. Genomic models implemented for traits with fewer QTLs showed even lower PA than the polygenic models.Genomic selection generally performed better than traditional polygenic selection, especially in the context of between family cross-validation. Reducing the number of markers considered to affect the trait did not significantly change PA for most traits, particularly in the case of within family cross-validation, but increased the number of markers found to be associated with QTLs. The underlying number of QTLs affecting the trait has an effect on PA, with a smaller number of QTLs resulting in lower PA using the genomic model compared to the polygenic model.
QTL detection of yield-related traits of cashew
Cavalcanti, José Jaime Vasconcelos;Santos, Francisco Herbeth Costa dos;Silva, Fanuel Pereira da;Pinheiro, Cássia Renata;
Crop Breeding and Applied Biotechnology , 2012, DOI: 10.1590/S1984-70332012000100008
Abstract: the identification of quantitative trait loci (qtl) and marker-assisted selection with a view to breeding programs have aroused great interest, including for cashew improvement. this study identified qtl for yield-related traits: nut weight, male and hermaphrodite flowers. the traits were evaluated in 71 f1 genotypes of the cross ccp 1001 x cp 96. the methods of interval mapping and multiple qtl mapping were applied to identify qtl. eleven qtl were detected: three for nut weight, four for male flowers and four for hermaphrodite flowers. the qtl accounted for 3.79 to 12.98 % of the total phenotypic variance and had phenotypic effects of -31.81 to 34.25 %. the potential for marker-assisted selection of the qtl hf-2f and hf-3m is great and the phenotypic effects and percentage of phenotypic variation higher than of the others.
NOTE - QTL detection of yield-related traits of cashew
José Jaime Vasconcelos Cavalcanti,Francisco Herbeth Costa dos Santos,Fanuel Pereira da Silva,Cássia Renata Pinheiro
Crop Breeding and Applied Biotechnology , 2012,
Abstract: The identification of quantitative trait loci (QTL) and marker-assisted selection with a view to breeding programs have aroused great interest, including for cashew improvement. This study identified QTL for yield-related traits: nut weight, male and hermaphrodite flowers. The traits were evaluated in 71 F1 genotypes of the cross CCP 1001 x CP 96. The methods of interval mapping and multiple QTL mapping were applied to identify QTL. Eleven QTL were detected: three for nut weight, four for male flowers and four for hermaphrodite flowers. The QTL accounted for 3.79 to 12.98 % of the total phenotypic variance and had phenotypic effects of -31.81 to 34.25 %. The potential for marker-assisted selection of the QTL hf-2f and hf-3m is great and the phenotypic effects and percentage of phenotypic variation higher than of the others.
山羊经济性状标记辅助选择的遗传效应分析 Genetic Effect of the Marker Assisted Selection on Economic Traits of Goats
沈 伟,潘庆杰,李 兰,秦国庆,耿社民 SHEN Wei,PAN Qing-jie,LI Lan,QIN Guo-qing,GENG She-min
遗传 , 2004,
Abstract: 本研究以辽宁绒山羊、柴达木绒山羊和柴达木山羊3个群体共147只山羊为研究对象,运用PAGE和RAPD技术对山羊的体重、绒产量和绒细度3个性状进行了与标记基因关系的遗传分析,结果表明:EsD2-2型、LAPBB型和PA-32-2型分别为体重、绒产量和绒细度性状的优势标记基因型;可利用标记辅助预测的方法充分利用多基因座标记基因间的互作效应;在体重上,寻找到有显著选择效应的RAPD条带11个,在绒产量和绒细度上分别为9和6个;在多目标性状选择中,CY0818/A0型和OPW19/C1型为体重和绒产量的双重优势RAPD标记,CY0818/G1型为体重和绒细度的双重优势RAPD标记。Abstract: The genetic relationships between economic traits and genetic markers were studied in 147 goats including Chaidamu goat (CS), Chaidamu Cashmere goat (CRS) and Liaoning Cashmere goat (LRS) in Qinghai province, China. CRS was the population of CS×LRS crossbred. The results showed as follows: the selection reaction of these blood protein polymorphisic loci were great, such as EsD, LAP and PA-3; and EsD2-2, LAPBB and PA-32-2 were the superior marker genotypes on body weight ,Cashmere yield and Cashmere fineness respectively by Least Square method. The interaction between marker genotypes at double loci was found frequently, and their ratio between interaction variance component and genetic varia
Marker assisted selection in BMQ related breeding programs  [PDF]
Obreht Dragana,Kobiljski Borislav,?an Mihajla,Vapa Ljiljana
Genetika , 2008, DOI: 10.2298/gensr0801039o
Abstract: Implementation of marker assisted selection (MAS) in bread making quality (BMQ) oriented breeding programs could allow genetic potential assessment of genotypes prior to their phenotypic evaluation. The mechanisms underlying some quality traits in wheat are now understood. This knowledge, coupled with the availability of the DNA sequences of the genes encoding gluten proteins and the wide application of the PCR, has enabled the design of diagnostic DNA markers for these quality traits. Bread wheat breeding programs developed in Institute of Field and Vegetable Crops, Novi Sad have originated a wide range of quality cultivars with strong flours and hard grain texture. During twenty years, in the process of bread-making quality prediction, composition of HMW glutenin subunits were analyzed beside standard technological parameters. However, in order to improve our breeding strategies new generations of PCR-based BMQ related markers were included in selection programs. This paper provides an overview of diagnostic DNA markers that are currently in use in foreign and domestic wheat selection programs. .
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