Mapping of markers related to self-incompatibility, disease resistance, and quality traits in Lolium perenne L.

Several linkage maps, mainly based on anonymous markers, are now available for Lolium perenne . The saturation of these maps with markers derived from expressed sequences would provide information useful for QTL mapping and map alignment. Therefore, we initiated a study to develop and map DNA markers in genes related to self-incompatibility, disease resistance, and quality traits such as digestibility and sugar content in two L. perenne families. In total, 483 and 504 primer pairs were designed and used to screen the ILGI and CLO-DvP mapping populations, respectively, for length polymorphisms. Finally, we were able to map 67 EST markers in at least one mapping population. Several of these markers coincide with previously reported QTL regions for the traits considered or are located in the neighbourhood of the self-incompatibility loci, S and Z. The markers developed expand the set of gene-derived markers available for genetic mapping in ryegrasses.

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Selective Mapping: A Strategy for Optimizing the Construction of High-Density Linkage Maps

Genetics ◽

10.1093/genetics/155.1.407 ◽

2000 ◽

Vol 155 (1) ◽

pp. 407-420

Author(s):

Todd J Vision ◽

Daniel G Brown ◽

David B Shmoys ◽

Richard T Durrett ◽

Steven D Tanksley

Keyword(s):

Mapping Population ◽

High Density ◽

Linkage Maps ◽

Radiation Hybrids ◽

Genome Wide ◽

Stochastic Optimization Problem ◽

Radiation Induced ◽

Selective Mapping ◽

Map Resolution ◽

Mapping Populations

Abstract Historically, linkage mapping populations have consisted of large, randomly selected samples of progeny from a given pedigree or cell lines from a panel of radiation hybrids. We demonstrate that, to construct a map with high genome-wide marker density, it is neither necessary nor desirable to genotype all markers in every individual of a large mapping population. Instead, a reduced sample of individuals bearing complementary recombinational or radiation-induced breakpoints may be selected for genotyping subsequent markers from a large, but sparsely genotyped, mapping population. Choosing such a sample can be reduced to a discrete stochastic optimization problem for which the goal is a sample with breakpoints spaced evenly throughout the genome. We have developed several different methods for selecting such samples and have evaluated their performance on simulated and actual mapping populations, including the Lister and Dean Arabidopsis thaliana recombinant inbred population and the GeneBridge 4 human radiation hybrid panel. Our methods quickly and consistently find much-reduced samples with map resolution approaching that of the larger populations from which they are derived. This approach, which we have termed selective mapping, can facilitate the production of high-quality, high-density genome-wide linkage maps.

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A Demonstration of a 1:1 Correspondence Between Chiasma Frequency and Recombination Using a Lolium perenne/Festuca pratensis Substitution

Genetics ◽

10.1093/genetics/161.1.307 ◽

2002 ◽

Vol 161 (1) ◽

pp. 307-314 ◽

Cited By ~ 7

Author(s):

J King ◽

L A Roberts ◽

M J Kearsey ◽

H M Thomas ◽

R N Jones ◽

...

Keyword(s):

Lolium Perenne ◽

Chiasma Frequency ◽

Chiasma Formation ◽

Grass Species ◽

Festuca Pratensis ◽

Single Chromosome ◽

Length Polymorphisms ◽

Amplified Fragment Length Polymorphisms ◽

Frequency Counts

Abstract A single chromosome of the grass species Festuca pratensis has been introgressed into Lolium perenne to produce a diploid monosomic substitution line (2n = 2x = 14). The chromatin of F. pratensis and L. perenne can be distinguished by genomic in situ hybridization (GISH), and it is therefore possible to visualize the substituted F. pratensis chromosome in the L. perenne background and to study chiasma formation in a single marked bivalent. Recombination occurs freely in the F. pratensis/L. perenne bivalent, and chiasma frequency counts give a predicted map length for this bivalent of 76 cM. The substituted F. pratensis chromosome was also mapped with 104 EcoRI/Tru91 and HindIII/Tru91 amplified fragment length polymorphisms (AFLPs), generating a marker map of 81 cM. This map length is almost identical to the map length of 76 cM predicted from the chiasma frequency data. The work demonstrates a 1:1 correspondence between chiasma frequency and recombination and, in addition, the absence of chromatid interference across the Festuca and Lolium centromeres.

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Self-incompatibility in ryegrass VI. Self seed-set and incompatibility genotype in Lolium perenne L

Heredity ◽

10.1038/hdy.1983.18 ◽

1983 ◽

Vol 50 (2) ◽

pp. 169-177 ◽

Cited By ~ 6

Author(s):

C H Fearon ◽

M D Hayward ◽

M J Lawrence

Keyword(s):

Lolium Perenne ◽

Seed Set ◽

Self Incompatibility ◽

Lolium Perenne L

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Advanced Strategies in Bulked Segregant Analysis and its Applications

Bhartiya Krishi Anusandhan Patrika ◽

10.18805/bkap327 ◽

2021 ◽

Author(s):

Harshavardan J. Hilli

Keyword(s):

Genetic Markers ◽

Mapping Population ◽

Bulked Segregant Analysis ◽

High Density ◽

Mutant Phenotype ◽

Linkage Maps ◽

Quick Method ◽

Reduced Time

Bulked segregant analysis (BSA) is a technique used to identify genetic markers associated with a mutant phenotype and is a quick method for identifying markers in particular genome regions. The paper focussed on Advanced methods which escape the requirement of genotyping all the individuals of the mapping population and generation of high-density linkage maps for mapping of the gene for the trait of interest. With the emergence of re-sequencing techniques, quick mapping of genes has become possible with reduced time and cost by using advanced methodologies like MutMap, MutMap+, MutMap-Gap, QTL-Seq, RNAseq BSA, NGS BSA and QTG seq. The procedure for various advanced BSA strategies has been described.

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Mapping mendelian factors underlying quantitative traits using RFLP linkage maps.

Genetics ◽

10.1093/genetics/121.1.185 ◽

1989 ◽

Vol 121 (1) ◽

pp. 185-199 ◽

Cited By ~ 119

Author(s):

E S Lander ◽

D Botstein

Keyword(s):

Dna Markers ◽

Quantitative Trait ◽

Quantitative Traits ◽

Human Genetics ◽

Substantial Reduction ◽

Interval Mapping ◽

Genetic Dissection ◽

Linkage Maps ◽

Phenotypic Effect ◽

Length Polymorphisms

Abstract The advent of complete genetic linkage maps consisting of codominant DNA markers [typically restriction fragment length polymorphisms (RFLPs)] has stimulated interest in the systematic genetic dissection of discrete Mendelian factors underlying quantitative traits in experimental organisms. We describe here a set of analytical methods that modify and extend the classical theory for mapping such quantitative trait loci (QTLs). These include: (i) a method of identifying promising crosses for QTL mapping by exploiting a classical formula of SEWALL WRIGHT; (ii) a method (interval mapping) for exploiting the full power of RFLP linkage maps by adapting the approach of LOD score analysis used in human genetics, to obtain accurate estimates of the genetic location and phenotypic effect of QTLs; and (iii) a method (selective genotyping) that allows a substantial reduction in the number of progeny that need to be scored with the DNA markers. In addition to the exposition of the methods, explicit graphs are provided that allow experimental geneticists to estimate, in any particular case, the number of progeny required to map QTLs underlying a quantitative trait.

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Molecular Markers for Powdery Mildew in Pea (Pisum sativum L.): A Review

Legume Research - An International Journal ◽

10.18805/lr-4740 ◽

2021 ◽

Author(s):

Reginah Pheirim ◽

Noren Singh Konjengbam ◽

Mayurakshee Mahanta

Keyword(s):

Disease Resistance ◽

Powdery Mildew ◽

Powdery Mildew Resistance ◽

Genetic Resistance ◽

Disease Resistance Gene ◽

Breeding Programs ◽

Biotic Stresses ◽

Pisum Sativum L ◽

Development And Utilization ◽

Mapping Populations

Powdery mildew is caused by an obligate parasite Erysiphe pisi and considered as one of the most important constraints causing yield reductions in pea. Development and utilization of genetic resistance is acknowledged as the most effective, economic and environmental friendly method of control. Therefore, development of cultivars with improved resistance to biotic stresses is a primary goal of plant breeding programs throughout the world. Three monogenic sources er1, er2 and Er3 have been described to govern the powdery mildew disease resistance. Several markers have been reported linked to resistant genes at varying distances in different mapping populations. Genetic markers linked to the disease resistance gene make the breeding process more efficient for the use of Marker Assisted Selection (MAS) strategy to aid in obtaining a complete powdery mildew resistance in pea.

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