This document discusses quantitative trait loci (QTL) mapping which is used to identify genetic markers linked to genes that influence quantitative traits. It involves 3 main steps: 1) creating a mapping population from a cross of two parental lines, 2) identifying polymorphic DNA markers, and 3) performing linkage analysis to analyze the linkage between markers and traits. Common mapping populations include F2, backcross, recombinant inbred lines, and doubled haploid lines. Linkage analysis uses statistical methods to calculate linkage between markers and traits based on recombination frequencies.

4. QTLsQTLsmolecular markersmolecular markers
Quantitative traitsQuantitative traits::
Quantitative trait lociQuantitative trait loci ((QTLsQTLs(:(:

5. Linkage mapLinkage map ((LMLM(:(:markersmarkers
LMLM
QTLsQTLsQTL mappingQTL mappingGenetic, gene or Genome mappingGenetic, gene or Genome mapping..
Gene taggingGene tagging::DNA markersDNA markersmarkersmarkersmarker-assistedmarker-assisted
selectionselection ((MASMAS(.(.

6. QTL mappingQTL mappingmarkersmarkersmarkersmarkers
Linkage mapLinkage map
11--Mapping populationsMapping populations..
22--Identification of polymorphismIdentification of polymorphism..
3- Linkage analysis of markers.3- Linkage analysis of markers.

7. 11--Mapping populationsMapping populations::
Linkage mapLinkage map
Genetic mappingGenetic mapping5050250250
QTLQTLMapping populationsMapping populationsQTL mappingQTL mapping..

8. Mapping populationsMapping populations::
11FF22FF11
22backcrossbackcrossFF11
mapping populationmapping population
33--Recombinant inbredRecombinant inbred ((RIRI
FF22
RIRI..
6688

9. RIRIDHDHHomozygousHomozygous
44Doubled haploidDoubled haploid ((DHDH
HaploidHaploid
plantsplants(.(.
Doubled haploidDoubled haploid..
DHDH
DHDH:: 11100100.%.%
22

11. 22--Identification of polymorphismIdentification of polymorphism::
Linkage mapLinkage mapDNA markersDNA markersPolymorphicmarkersPolymorphicmarkers.(.(
PolymorphismPolymorphismLinkage mapLinkage mapPolymorphismPolymorphism

12. polymorphic markerspolymorphic markersscreeningscreeningmapping populationmapping populationFF11
genotypinggenotypingDNADNA
GenotypingGenotyping::
screeningscreeningDNA markersDNA markersmarkermarker..

14. 33--Linkage analysis of markersLinkage analysis of markers::
Linkage mapLinkage mapcoding datacoding dataDNA markersDNA markerslinkagelinkage
analysisanalysis..
markersmarkers..
linkageslinkagesmarkersmarkersmapsmaps..
markersmarkersodds ratiosodds ratios..
Odds ratioOdds ratio::

15. 33) >) >LODLODLinkage mapLinkage map..
33) =) =LODLODtwo markerstwo markerslinkagelinkage10001000no linkagesno linkages (1:1000(1:1000))..
33) <) <LODLODtwo markerstwo markers..
linkage maplinkage map
))LOD) logarithm of oddsLOD) logarithm of odds..
33--join mapjoin map..
11--map marker/EXPmap marker/EXP..
22--map manager QTXmap manager QTX..

16. Linked markersLinked markersmarkersmarkerslinkage grouplinkage group
genetic distancegenetic distancemarkermarkermapping populationmapping populationmappingmapping
populationpopulation5050––100100200200––300300Linkage mapLinkage map..
Linkage groupsLinkage groups::markersmarkers