Molecular plant breeding some basic information

I would like to share this presentation file.
Some basics information regarding to molecular plant breeding, hope this help the beginner who start working in this field.

Thanks for many original source of information (mainly from slideshare.net, IRRI, CIMMYT and any paper received from professor and some over the internet)

1. Molecular Breeding and Marker Assisted
Selection
Molecular Breeding and Marker Assisted
Selection
Bawonpon C.

2. Outline
•DNA Fingerprinting
•Marker Assisted Selection (MAS)
•Marker Assisted Backcross (MABC)
•Marker Assisted Pyramiding
•Quantitative Trait Loci (QTL)
•Marker Assisted Recurrent Selection(MARS)
•Genomic Selection
•DNA Fingerprinting
•Marker Assisted Selection (MAS)
•Marker Assisted Backcross (MABC)
•Marker Assisted Pyramiding
•Quantitative Trait Loci (QTL)
•Marker Assisted Recurrent Selection(MARS)
•Genomic Selection

3. Thedifferencesthatdistinguishoneplantfromanotherareencodedinthe
plant’sgeneticmaterial,theDNA.DNAispackagedinchromosomepairs,
onecomingfromeachparent.Thegenes,whichcontrolaplant’s
characteristics,arelocatedonspecificsegmentsofeachchromosome.
Introduction
Genetic diversity
Thedifferencesthatdistinguishoneplantfromanotherareencodedinthe
plant’sgeneticmaterial,theDNA.DNAispackagedinchromosomepairs,
onecomingfromeachparent.Thegenes,whichcontrolaplant’s
characteristics,arelocatedonspecificsegmentsofeachchromosome.
http://www.isaaa.org/resources/publications/pocketk/19/default.asp

4. DNA Fingerprinting
DNA fingerprinting,also calledDNA typing,DNA profiling,genetic
fingerprinting, genotyping,oridentity testing,is genetics method
used for isolating andidentification the base-pair pattern in
individual’s DNA
•PaternityandMaternitytest
•PlantVarietyProtection
•Geneticpuritytest
•Studyingbiodiversity
•Tracking genetically modified crops
DNA fingerprinting is used in several ways.
DNA fingerprinting,also calledDNA typing,DNA profiling,genetic
fingerprinting, genotyping,oridentity testing,is genetics method
used for isolating andidentification the base-pair pattern in
individual’s DNA
•PaternityandMaternitytest
•PlantVarietyProtection
•Geneticpuritytest
•Studyingbiodiversity
•Tracking genetically modified crops

5. DNA Fingerprinting
An Example: Using DNA inPaternity and Maternity test / Plant variety
protection and genetic purity test
marker
F
1
FM
1
2
3
4
5
6
S
1S
2
F=femaleparent,M=maleparent
F1=Hybrid
S1=Sample#1
:Samefemale/differentmale
S2=Sample#2
:Differentfemale/Samemale
Testing can be done on seed or leaf
marker
5
6
7
8
9
10
DNA profile using10different marker (dominant
marker)
F=femaleparent,M=maleparent
F1=Hybrid
S1=Sample#1
:Samefemale/differentmale
S2=Sample#2
:Differentfemale/Samemale

6. DNA Fingerprinting
Genotype(variety)
Studying biodiversity
marker
Genotype(variety)
v
3………………………………………………………….. v
15v
1v
2
1
2
3
4
5
6
7
8
9
10
marker
DNA amplification profile of15genotype using10different marker
(dominant marker)
9
10

7. DNA Fingerprinting
•Genetic distance
•Cluster analysis
Useful information for
Breeder to arrange
heteroticgroup
Variation of DNA fingerprints among accessions within maize inbred lines and implications for identification of essentially derived varieties.
Molecular Breeding10:181–191,2002

8. Molecular Breeding
Molecularbreeding(MB)maybedefinedinabroad-senseastheuseof
geneticmanipulationperformedatDNAmolecularlevelstoimprovecharactersof
interestinplantsandanimals(MAB+GMO)
Marker-assistedbreeding(MAB)andisdefinedastheapplicationof
molecularbiotechnologies,specificallymolecularmarkers,incombinationwith
linkagemapsandgenomics,toimproveplantoranimaltraitsonthebasisof
genotypicassaysthistermiscoveredseveralmodernbreedingstrategies,
includingmarker-assistedselection(MAS),marker-assistedbackcrossing(MABC),
marker-assistedrecurrentselection(MARS),andgenome-wideselection(GWS)or
genomicselection(GS)(Ribautetal.,2010)
Molecularbreeding(MB)maybedefinedinabroad-senseastheuseof
geneticmanipulationperformedatDNAmolecularlevelstoimprovecharactersof
interestinplantsandanimals(MAB+GMO)
Marker-assistedbreeding(MAB)andisdefinedastheapplicationof
molecularbiotechnologies,specificallymolecularmarkers,incombinationwith
linkagemapsandgenomics,toimproveplantoranimaltraitsonthebasisof
genotypicassaysthistermiscoveredseveralmodernbreedingstrategies,
includingmarker-assistedselection(MAS),marker-assistedbackcrossing(MABC),
marker-assistedrecurrentselection(MARS),andgenome-wideselection(GWS)or
genomicselection(GS)(Ribautetal.,2010)
Molecularbreeding(MB)maybedefinedinabroad-senseastheuseof
geneticmanipulationperformedatDNAmolecularlevelstoimprovecharactersof
interestinplantsandanimals(MAB+GMO)
Marker-assistedbreeding(MAB)andisdefinedastheapplicationof
molecularbiotechnologies,specificallymolecularmarkers,incombinationwith
linkagemapsandgenomics,toimproveplantoranimaltraitsonthebasisof
genotypicassaysthistermiscoveredseveralmodernbreedingstrategies,
includingmarker-assistedselection(MAS),marker-assistedbackcrossing(MABC),
marker-assistedrecurrentselection(MARS),andgenome-wideselection(GWS)or
genomicselection(GS)(Ribautetal.,2010)
Guo-Liang Jiang: Molecular Markers and Marker-Assisted Breeding in Plants

9. Some traits, like flower color, may be controlled by only
one gene. Other more complex characteristics like crop
yield or starch content, may be influenced by many genes.
Traditionally,plant breeders have selected plants based on
their visible or measurable traits, called thephenotype.
This process can be difficult, slow and influenced by the
environment.
Molecular Breeding
Some traits, like flower color, may be controlled by only
one gene. Other more complex characteristics like crop
yield or starch content, may be influenced by many genes.
Traditionally,plant breeders have selected plants based on
their visible or measurable traits, called thephenotype.
This process can be difficult, slow and influenced by the
environment.
http://www.isaaa.org/resources/publications/pocketk/19/default.asp

10. USING MOLECULAR MARKERS
Some ofthe advantages of using molecular markers instead of
phenotypesto select are:
o Early selection (at seedling, or even for seeds)
o Reduced cost (fewer plants, shorter time)
o Reduced cycle time (if gene is recessive or measured after
flowering)
o Screening more efficient (if it is a complex trait)
Moreaux,2011
Molecular Breeding
USING MOLECULAR MARKERS
Some ofthe advantages of using molecular markers instead of
phenotypesto select are:
o Early selection (at seedling, or even for seeds)
o Reduced cost (fewer plants, shorter time)
o Reduced cycle time (if gene is recessive or measured after
flowering)
o Screening more efficient (if it is a complex trait)
Moreaux,2011
Chance to select the
right plant before
flowering
Chance to select heterozygous plant
USING MOLECULAR MARKERS
Some ofthe advantages of using molecular markers instead of
phenotypesto select are:
o Early selection (at seedling, or even for seeds)
o Reduced cost (fewer plants, shorter time)
o Reduced cycle time (if gene is recessive or measured after
flowering)
o Screening more efficient (if it is a complex trait)
Moreaux,2011

11. •Marker Assisted Selection (MAS)
•Marker Assisted Backcross (MABC)
•Marker Assisted Pyramiding
•Marker Assisted Recurrent Selection (MARS)
•Quantitative Trait Loci (QTL)
•Genomic Selection
Molecular Breeding Method
Molecular Breeding
•Marker Assisted Selection (MAS)
•Marker Assisted Backcross (MABC)
•Marker Assisted Pyramiding
•Marker Assisted Recurrent Selection (MARS)
•Quantitative Trait Loci (QTL)
•Genomic Selection
•Marker Assisted Selection (MAS)
•Marker Assisted Backcross (MABC)
•Marker Assisted Pyramiding
•Marker Assisted Recurrent Selection (MARS)
•Quantitative Trait Loci (QTL)
•Genomic Selection

12. Marker Assisted Selection (MAS)
The use of DNA markers that are tightly-linked to
target locias a substitute for orto assist phenotypic
screening orselection.
Molecular Breeding Method
Marker Assisted Selection (MAS)
The use of DNA markers that are tightly-linked to
target locias a substitute for orto assist phenotypic
screening orselection.

13. Marker Assisted Selection
Early generation selection
The mainadvantage is to discard
many plant with unwanted gene
combinations, especially those
that lack essential disease
resistance traits .
This has important in the later
stages of the breeding program
because the evaluation for other
traits can be more efficientlyand
cheaply designed for fewer
breeding lines .
Early generation selection
The mainadvantage is to discard
many plant with unwanted gene
combinations, especially those
that lack essential disease
resistance traits .
This has important in the later
stages of the breeding program
because the evaluation for other
traits can be more efficientlyand
cheaply designed for fewer
breeding lines .
http://www.knowledgebank.irri.org/ricebreedingcourse/Marker_assisted_breeding.htm
Early generation selection
The mainadvantage is to discard
many plant with unwanted gene
combinations, especially those
that lack essential disease
resistance traits .
This has important in the later
stages of the breeding program
because the evaluation for other
traits can be more efficientlyand
cheaply designed for fewer
breeding lines .

14. Marker Assisted Selection: An example with sweet corn
Most well known sweetness gene
se 2Sugar enhanced

15. Marker Assisted Selection
Category GeneSweetnessTextureFlavorGermination
/Vigor
Shelf life
Important gene controlling endosperm in sweet corn
Germination
/Vigor
Standard sweetsu1 10%
sucrose
creamygood good short
Sugar-enhanced se 2X sucrosecreamygood good longer
Super sweet sh2,bt1,
bt2
3X-8X
sucrose
Less
creamy
poor poor Longsh2,bt1,
bt2
3X-8X
sucrose
Less
creamy
KamolLertrat/TaweesakPulam: Breeding forincresingsweetness in corn

16. Marker Assisted Selection
In recent years new varieties have been developed that have
different combinations of the three major genes (su, se and
sh2) ‘stacked’ together.
In recent years new varieties have been developed that have
different combinations of the three major genes (su, se and
sh2) ‘stacked’ together.
Category Kernelstype Advantage Variety name
Highsugar sweet
corn
•25% sh2kernels
•25% se kernels
•50%sukernels
•suvigor
•higher sugar
•Sweet Chorus
•Sweet Rhythm
High sugar sweet
corn
•100% sh2kernel
•se trait in all kernels
•high sugar
•long shelf life
•tender
•Gourmet Sweet™
•Multisweet™
•Xtra-Tender Brand™
http://www.uvm.edu/vtvegandberry/factsheets/corngenotypes.html

17. Marker Assisted Backcross (MABC)
MABCaims to transfer one or a few genes/QTLs of
Interest from one genetic source into a superior
cultivar or elite breeding lineto improve the
targeted trait.
Molecular Breeding Method
Marker Assisted Backcross (MABC)
MABCaims to transfer one or a few genes/QTLs of
Interest from one genetic source into a superior
cultivar or elite breeding lineto improve the
targeted trait.

18. Two levelsof selection in which markers may beapplied in
backcross breeding.
•Selectbackcrossprogeny carrying the target genewhich
tightly-linked to flanking markers (foreground selection).
•Selectbackcrossprogeny withbackground markers
(background selection) to accelerate therecovery of the
recurrent parent genome.
Marker Assisted Backcross
Two levelsof selection in which markers may beapplied in
backcross breeding.
•Selectbackcrossprogeny carrying the target genewhich
tightly-linked to flanking markers (foreground selection).
•Selectbackcrossprogeny withbackground markers
(background selection) to accelerate therecovery of the
recurrent parent genome.
Two levelsof selection in which markers may beapplied in
backcross breeding.
•Selectbackcrossprogeny carrying the target genewhich
tightly-linked to flanking markers (foreground selection).
•Selectbackcrossprogeny withbackground markers
(background selection) to accelerate therecovery of the
recurrent parent genome.

19. Marker Assisted Backcross (MABC)
FOREGROUND SELECTION
Use markers to transfer genes or QTL of
major effects. One or multiple genes
may be transferred. Markers should be
closely linked to the gene of interest to
avoid loosing them by recombination
BACKGROUND SELECTION
Use markers to control for genetic
background in a BC cycle. To speed the
process of recovery of the elite
germplasm, markers may be used along
the genome.
FOREGROUND SELECTION
Use markers to transfer genes or QTL of
major effects. One or multiple genes
may be transferred. Markers should be
closely linked to the gene of interest to
avoid loosing them by recombination
BACKGROUND SELECTION
Use markers to control for genetic
background in a BC cycle. To speed the
process of recovery of the elite
germplasm, markers may be used along
the genome.
Marker
FG+BG
Highest RPG
Carrying target gene
http://passel.unl.edu/pages/informationmodule.php?idinformationmodule=1087488148&topicorder=7&maxto=10
FOREGROUND SELECTION
Use markers to transfer genes or QTL of
major effects. One or multiple genes
may be transferred. Markers should be
closely linked to the gene of interest to
avoid loosing them by recombination
BACKGROUND SELECTION
Use markers to control for genetic
background in a BC cycle. To speed the
process of recovery of the elite
germplasm, markers may be used along
the genome.
Marker
FG
Conversion
completed

20. resistance donor P1XP2 F1BC1F1 BC2F1 BC3F1
Marker Assisted Backcross (MABC)
Background selection:
Increase the level of recovering recurrent parent genome in BC generation
Faster recovering
RP genome
DNA marker
chrom1
Targetgene chrom2
chrom3
#plants
number plants to consider
Faster recovering
RP genome
number plants to consider
withoutand marker data
#plants
50% 100%
%recurrentparent
genomeinBC1F1
50% 100%
%recurrentparen
genomeinBC1F1
with
Decrease number of
Plant to consider

21. Marker Assisted Pyramiding
Pyramiding is the process of combining multiple genes/QTLs together
into a single genotype.This is possible through conventional breeding
but extremely difficult or impossible at early generations.DNA markers
may facilitate selection because :
•DNA marker assays are non-destructive
•Markers for multiple specific genes/QTLscan be tested without
phenotyping.
•The most widespreadapplication for pyramiding has been for
combining multiple disease resistance genesin order to develop durable
disease resistance.
Molecular Breeding Method
Pyramiding is the process of combining multiple genes/QTLs together
into a single genotype.This is possible through conventional breeding
but extremely difficult or impossible at early generations.DNA markers
may facilitate selection because :
•DNA marker assays are non-destructive
•Markers for multiple specific genes/QTLscan be tested without
phenotyping.
•The most widespreadapplication for pyramiding has been for
combining multiple disease resistance genesin order to develop durable
disease resistance.
Pyramiding is the process of combining multiple genes/QTLs together
into a single genotype.This is possible through conventional breeding
but extremely difficult or impossible at early generations.DNA markers
may facilitate selection because :
•DNA marker assays are non-destructive
•Markers for multiple specific genes/QTLscan be tested without
phenotyping.
•The most widespreadapplication for pyramiding has been for
combining multiple disease resistance genesin order to develop durable
disease resistance.
http://www.knowledgebank.irri.org/ricebreedingcourse/Marker_assisted_breeding.htm

22. Marker Assisted Pyramiding
Segregating population
Marker tightly link
to the gene
Marker tightly link
to the gene
Select by marker
Instead ofphenotyping
In early generation
Fixed2resistant gene

23. Marker Assisted Pyramiding
Gene pyramiding in major crop

24. Marker Assisted Pyramiding
Marker-aided selection (MAS)-improved varieties developed by NARES teams from
Philippines, Indonesia, India and China,2002-2003
Example: Pyramiding ofxagene (blbresistant gene) in rice
Country Background
commercial/
Yield standard
Released (R) / Near-release (NR) +
Introgressed gene(s)
Yield
(t/ha)
Gainover
yield std (%)
PhilippinesIR64 AR32-19-3-2(xa5/Xa21)(NR) 5.1 0
IR64 AR32-19-3-3(xa5, Xa21)(NR) 6.7 31.4
IR64 AR32-19-3-4(xa5/Xa21)(NR) 6.1 19.6
BPIRi10 AR32-4-3-1(xa5/Xa21)(NR) 6.0 17.6
BPI Ri10 AR32-4-58-2(xa5/Xa21)(NR) 6.5 27.5
PSBRc28 Yield standard 5.1 -
Indonesia IR64 Angke (Bio1)(Xa4/xa5)(R) 5.4 20.0
5.1 -
Indonesia IR64 Angke (Bio1)(Xa4/xa5)(R) 5.4 20.0
IR64 Conde(Bio2)(Xa4/Xa7)(R) 5.4 20.0
IR64 Yield standard(Xa4) 4.5 -
India PR106 IET17948(xa5/xa13/Xa21)(NR) 8.2 22.4
PR106 IET17949(xa5/xa13/Xa21) NR) 7.9 17.9
PR106 Yield standard 6.7 -
China Zhong9A/Zhonghui
218
Hybrid Guofeng No.2(Xa21)(HR,NR) 7.8 11.4
II-3A/Zhonghui218 Hybrid II You218(Xa21)(HR, R) 8.3 18.6
Shanyou46 Yield standard 7.0 -
(

25. Marker Assisted Pyramiding
MAS-improved pyramided IR64with xa5, Xa7and Xa21
Susceptible
Resistant
Susceptible

26. Quantitative Trait Loci (QTL)
Quantitative trait
•Trait that show continuous variation in population
•combined effect of several genes
•bell curve distribution of phenotypic values, produces a range of phenotypes
Quantitative trait
•Trait that show continuous variation in population
•combined effect of several genes
•bell curve distribution of phenotypic values, produces a range of phenotypes
Variety A
Variety B
Quantitative trait
-Plant height
-Grain yield
-Some disease resistant
frequency
Trait value
Purpose of QTL study using in plant breeding is
1.To localizechromosomal region that significantly effect
the variation of quantitative trait in the population
2.Introgression of favorable QTLs region in to elite variety
QTL mapping

27. Quantitative Trait Loci (QTL)
Aquantitativetraitlocus/loci(QTL)isthelocationor
regionofindividuallocusormultiplelociinthegenomethat
affectsatraitthatismeasuredonaquantitative.
•Developmappingpopulation(F2,DH,NIL,BC,RIL)
•Genotyping(Polymorphicmarker)
•Constructingoflinkagemaps(linkagebetweenmarker)
•Phenotyping(screeninfield)
•QTLsanalysis
-Test associationbetweenphenotypictrait and marker
-Identify major /minor QTL
QTLsmappingprocess
Aquantitativetraitlocus/loci(QTL)isthelocationor
regionofindividuallocusormultiplelociinthegenomethat
affectsatraitthatismeasuredonaquantitative.
•Developmappingpopulation(F2,DH,NIL,BC,RIL)
•Genotyping(Polymorphicmarker)
•Constructingoflinkagemaps(linkagebetweenmarker)
•Phenotyping(screeninfield)
•QTLsanalysis
-Test associationbetweenphenotypictrait and marker
-Identify major /minor QTL

28. Quantitative Trait Loci (QTL): An example with rice
Linkage maps
Identifying novel QTLs for submergence tolerance in rice cultivars IR72andMada:baru:TheorApplGenet (2012)124:867–874DOI10.1007/s00122-011-1751-0

29. Quantitative Trait Loci (QTL): An example with rice
QTL analysis
Identifying novel QTLs for submergence tolerance in rice cultivars IR72andMada:baru:TheorApplGenet (2012)124:867–874DOI10.1007/s00122-011-1751-0
LOD explain linkage between marker and QTLs
R
2
explain phenotypic variance by QTLs (PVE)
Transfer QTL to elitegermplasm
Validate QTLs

30. Marker Assisted Recurrent Selection (MARS)
Whenmuchofthevariationiscontrolledbymany
minorQTLs(20-30QTLs),MABChaslimitedapplicability
becauseestimatesofQTLeffectsareinconsistentand
gene pyramidingbecomesincreasinglydifficultasthe
numberofQTLsincreases.
A moreeffective strategy is to deploy MARS to
increase the frequency offavorable marker allelesin
thepopulation.
Whenmuchofthevariationiscontrolledbymany
minorQTLs(20-30QTLs),MABChaslimitedapplicability
becauseestimatesofQTLeffectsareinconsistentand
gene pyramidingbecomesincreasinglydifficultasthe
numberofQTLsincreases.
A moreeffective strategy is to deploy MARS to
increase the frequency offavorable marker allelesin
thepopulation.
RobertoTuberosa:Dept.ofAgroenvironmentalSciences and Technology , UniversityofBologna,Italy
Whenmuchofthevariationiscontrolledbymany
minorQTLs(20-30QTLs),MABChaslimitedapplicability
becauseestimatesofQTLeffectsareinconsistentand
gene pyramidingbecomesincreasinglydifficultasthe
numberofQTLsincreases.
A moreeffective strategy is to deploy MARS to
increase the frequency offavorable marker allelesin
thepopulation.

31. Marker Assisted Recurrent Selection (MARS)
MARSinvolves:
•Defininga selectionindexforF
2
orF
2
-derived
progenies,use index to weight significant marker for
target QTLs(20-30QTLs)
•Recombiningselfedprogenies of the selected
individuals
•Repeat the procedurefor a number of cycles
MARSinvolves:
•Defininga selectionindexforF
2
orF
2
-derived
progenies,use index to weight significant marker for
target QTLs(20-30QTLs)
•Recombiningselfedprogenies of the selected
individuals
•Repeat the procedurefor a number of cycles
RobertoTuberosa:Dept.ofAgroenvironmentalSciences and Technology , UniversityofBologna,Italy

32. Marker Assisted Recurrent Selection (MARS)
Stepsin aMARS in Maize:
1.MAS in Cycle0
•CreateanF2(Cycle0)
•Test-crosstheF2
•Evaluateprogenyin multipleenvironments
•Identifymarkersassociatedwithtraitofinterest
•Createanindexweightingsignificantmarkers
bytheireffect usingmultiple linearregression
(LandeandThompson1990).
•Recombinebestprogeny(bestindividualsfromCycle0)
2.Selectin greenhouseoroff-seasonnursery(upto3
cyclesin low h
2
environment).
1.MAS in Cycle0
•CreateanF2(Cycle0)
•Test-crosstheF2
•Evaluateprogenyin multipleenvironments
•Identifymarkersassociatedwithtraitofinterest
•Createanindexweightingsignificantmarkers
bytheireffect usingmultiple linearregression
(LandeandThompson1990).
•Recombinebestprogeny(bestindividualsfromCycle0)
2.Selectin greenhouseoroff-seasonnursery(upto3
cyclesin low h
2
environment).
Patricio J.MayorandRexBernardo:
GenomewideSelection and Marker-Assisted Recurrent Selection in Doubled Haploid
versus F
2Populations
1.MAS in Cycle0
•CreateanF2(Cycle0)
•Test-crosstheF2
•Evaluateprogenyin multipleenvironments
•Identifymarkersassociatedwithtraitofinterest
•Createanindexweightingsignificantmarkers
bytheireffect usingmultiple linearregression
(LandeandThompson1990).
•Recombinebestprogeny(bestindividualsfromCycle0)
2.Selectin greenhouseoroff-seasonnursery(upto3
cyclesin low h
2
environment).

33. Genomic Selection
Genomic selection (GS) is a new approach for
improving quantitative traitsin large plant
breeding populations thatuses whole genome
molecular markersandcombines marker data
with phenotypic datain an attempttoincrease
the accuracy of theprediction of breeding and
genotypic values.
Genomic selection (GS) is a new approach for
improving quantitative traitsin large plant
breeding populations thatuses whole genome
molecular markersandcombines marker data
with phenotypic datain an attempttoincrease
the accuracy of theprediction of breeding and
genotypic values.
Genomic selection (GS) is a new approach for
improving quantitative traitsin large plant
breeding populations thatuses whole genome
molecular markersandcombines marker data
with phenotypic datain an attempttoincrease
the accuracy of theprediction of breeding and
genotypic values.
http://genomics.cimmyt.org/

34. Genomic Selection
ObjectiveofGSistopredictthebreedingvalueofeach
individualinsteadofidentifyingQTLforuseinatraditional
marker-assistedselection(MAS)program
•Requireshigh-densitymolecularmarkers(LDlevel)
•GSconsiderstheeffectsofallmarkerstogetherand capturesmostof
theadditivevariation
•Markereffectsarefirst estimatedbasedona so-called
“trainingpopulation”thatneedsto besufficientlylarge(>300)
•Breedingvalueis thenpredictedfor eachgenotypeinthe
“testingpopulation”usingtheestimatedmarkereffects
ObjectiveofGSistopredictthebreedingvalueofeach
individualinsteadofidentifyingQTLforuseinatraditional
marker-assistedselection(MAS)program
•Requireshigh-densitymolecularmarkers(LDlevel)
•GSconsiderstheeffectsofallmarkerstogetherand capturesmostof
theadditivevariation
•Markereffectsarefirst estimatedbasedona so-called
“trainingpopulation”thatneedsto besufficientlylarge(>300)
•Breedingvalueis thenpredictedfor eachgenotypeinthe
“testingpopulation”usingtheestimatedmarkereffects
RobertoTuberosa:Dept.ofAgroenvironmentalSciences and Technology , UniversityofBologna,Italy

35. Genomic Selection Scheme
Statistic model
Genomic Selection Scheme
Predict trait value
base on genotype
result
Selection orintermatefor
Next cycle
Predict trait value
base on genotype
result

36. THANKSTHANKS
Thanks!