Comparative genetic linkage maps of Eucalyptus grandis, Eucalyptus globulus and their F1 hybrid based on a double pseudo-backcross mapping approach

Abstract We have used a "two-way pseudo-testcross" mapping strategy in combination with the random amplified polymorphic DNA (RAPD) assay to construct two moderate density genetic linkage maps for species of Eucalyptus. In the cross between two heterozygous individuals many single-dose RAPD markers will be heterozygous in one parent, null in the other and therefore segregate 1:1 in their F1 progeny following a testcross configuration. Meiosis and gametic segregation in each individual can be directly and efficiently analyzed using RAPD markers. We screened 305 primers of arbitrary sequence, and selected 151 to amplify a total of 558 markers. These markers were grouped at LOD 5.0, theta = 0.25, resulting in the maternal Eucalyptus grandis map having a total of 240 markers into 14 linkage groups (1552 cM) and the paternal Eucalyptus urophylla map with 251 markers in 11 linkage groups (1101 cM) (n = 11 in Eucalyptus). Framework maps ordered with a likelihood support > or = 1000:1 were assembled covering 95% of the estimated genome size in both individuals. Characterization of genome complexity of a sample of 48 mapped random amplified polymorphic DNA (RAPD) markers indicate that 53% amplify from low copy regions. These are the first reported high coverage linkage maps for any species of Eucalyptus and among the first for any hardwood tree species. We propose the combined use of RAPD markers and the pseudo-testcross configuration as a general strategy for the construction of single individual genetic linkage maps in outbred forest trees as well as in any highly heterozygous sexually reproducing living organisms. A survey of the occurrence of RAPD markers in different individuals suggests that the pseudo-testcross/RAPD mapping strategy should also be efficient at the intraspecific level and increasingly so with crosses of genetically divergent individuals. The ability to quickly construct single-tree genetic linkage maps in any forest species opens the way for a shift from the paradigm of a species index map to the heterodox proposal of constructing several maps for individual trees of a population, therefore mitigating the problem of linkage equilibrium between marker and trait loci for the application of marker assisted strategies in tree breeding.

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High-density genetic linkage maps with over 2,400 sequence-anchored DArT markers for genetic dissection in an F2 pseudo-backcross of Eucalyptus grandis × E. urophylla

Tree Genetics & Genomes ◽

10.1007/s11295-011-0430-2 ◽

2011 ◽

Vol 8 (1) ◽

pp. 163-175 ◽

Cited By ~ 28

Author(s):

Anand Raj Kumar Kullan ◽

Maria M. van Dyk ◽

Nicoletta Jones ◽

Arnulf Kanzler ◽

Arlene Bayley ◽

...

Keyword(s):

Genetic Linkage ◽

Eucalyptus Grandis ◽

High Density ◽

Dart Markers ◽

Genetic Dissection ◽

Linkage Maps ◽

Genetic Linkage Maps

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Construction of genetic linkage maps of silver birch based on AFLP markers

Hereditas (Beijing) ◽

10.3724/sp.j.1005.2009.00213 ◽

2009 ◽

Vol 31 (2) ◽

pp. 213-218 ◽

Cited By ~ 1

Author(s):

Fu-Ling GAO ◽

Ting-Bo JIANG

Keyword(s):

Genetic Linkage ◽

Silver Birch ◽

Aflp Markers ◽

Linkage Maps ◽

Genetic Linkage Maps

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VfODB: a comprehensive database of ESTs, EST-SSRs, mtSSRs, microRNA-target markers and genetic maps in Vicia faba

AoB Plants ◽

10.1093/aobpla/plaa064 ◽

2020 ◽

Vol 12 (6) ◽

Author(s):

Morad M Mokhtar ◽

Ebtissam H A Hussein ◽

Salah El-Din S El-Assal ◽

Mohamed A M Atia

Keyword(s):

Vicia Faba ◽

Faba Bean ◽

Expressed Sequence Tags ◽

Genetic Linkage ◽

Genetic Maps ◽

Linkage Maps ◽

Microrna Target ◽

Genetic Linkage Maps ◽

Expressed Sequence ◽

Simple Sequence

Abstract Faba bean (Vicia faba) is an essential food and fodder legume crop worldwide due to its high content of proteins and fibres. Molecular markers tools represent an invaluable tool for faba bean breeders towards rapid crop improvement. Although there have historically been few V. faba genome resources available, several transcriptomes and mitochondrial genome sequence data have been released. These data in addition to previously developed genetic linkage maps represent a great resource for developing functional markers and maps that can accelerate the faba bean breeding programmes. Here, we present the Vicia faba Omics database (VfODB) as a comprehensive database integrating germplasm information, expressed sequence tags (ESTs), expressed sequence tags-simple sequence repeats (EST-SSRs), and mitochondrial-simple sequence repeats (mtSSRs), microRNA-target markers and genetic maps in faba bean. In addition, KEGG pathway-based markers and functional maps are integrated as a novel class of annotation-based markers/maps. Collectively, we developed 31 536 EST markers, 9071 EST-SSR markers and 3023 microRNA-target markers based on V. faba RefTrans V2 mining. By mapping 7940 EST and 2282 EST-SSR markers against the KEGG pathways database we successfully developed 107 functional maps. Also, 40 mtSSR markers were developed based on mitochondrial genome mining. On the data curation level, we retrieved 3461 markers representing 12 types of markers (CAPS, EST, EST-SSR, Gene marker, INDEL, Isozyme, ISSR, RAPD, SCAR, RGA, SNP and SSR), which mapped across 18 V. faba genetic linkage maps. VfODB provides two user-friendly tools to identify, classify SSR motifs and in silico amplify their targets. VfODB can serve as a powerful database and helpful platform for faba bean research community as well as breeders interested in Genomics-Assisted Breeding.

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Integrating Genetic Linkage Maps With Pachytene Chromosome Structure in Maize

Genetics ◽

10.1093/genetics/166.4.1923 ◽

2004 ◽

Vol 166 (4) ◽

pp. 1923-1933 ◽

Cited By ~ 8

Author(s):

Lorinda K Anderson ◽

Naser Salameh ◽

Hank W Bass ◽

Lisa C Harper ◽

W Z Cande ◽

...

Keyword(s):

Genetic Linkage ◽

Chromosome Structure ◽

Single Copy ◽

Chromosome 9 ◽

Linkage Maps ◽

Cytogenetic Map ◽

Recombination Nodules ◽

Novel Approach ◽

Genetic Linkage Maps ◽

High Degree

Abstract Genetic linkage maps reveal the order of markers based on the frequency of recombination between markers during meiosis. Because the rate of recombination varies along chromosomes, it has been difficult to relate linkage maps to chromosome structure. Here we use cytological maps of crossing over based on recombination nodules (RNs) to predict the physical position of genetic markers on each of the 10 chromosomes of maize. This is possible because (1) all 10 maize chromosomes can be individually identified from spreads of synaptonemal complexes, (2) each RN corresponds to one crossover, and (3) the frequency of RNs on defined chromosomal segments can be converted to centimorgan values. We tested our predictions for chromosome 9 using seven genetically mapped, single-copy markers that were independently mapped on pachytene chromosomes using in situ hybridization. The correlation between predicted and observed locations was very strong (r2 = 0.996), indicating a virtual 1:1 correspondence. Thus, this new, high-resolution, cytogenetic map enables one to predict the chromosomal location of any genetically mapped marker in maize with a high degree of accuracy. This novel approach can be applied to other organisms as well.

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