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Sukhwinder SinghWheat-Lead, Seeds of Discovery (SeeD)
International Maize and Wheat Improvement Center (CIMMYT), Apdo. Postal 6-641, 06600, Mexico DF, Mexico
IWC- Sept., 22, 2015
Gene Bank Biodiversity for Wheat Prebreeding
Posters # P083 & P085
seedsofdiscovery.org/wheat/
1. Pre-green revolution era
2. Green revolution era
?3. Climate change era
Why Use Gene Bank Biodiversity?
Next generation variety = Climate resilience + Yield + Input efficient
Genetic resourcesGenomics
Trait focus
Bottlenecks in conventional breeding
Improve efficiency Enhance precision
Mobilize gene bank for novel variation Exploit
• Transgressive segregation• Recombination
An Inclusive Approach at CIMMYT: SeeD-Wheat
Stress tolerance Quality
Genetic Resources
+Genomics tools= Pre breeding
Synergistic approach: Capture value of germplasm resources through genomics
8000 Mexican landraces
Phenotype(Heat, Drought, Quality)
GBS profiling(20K SNPs)
(A) Diversity analysis (B) Core set development
(C) Core set evaluation(D) Trait donor identification(E) Pre-breedingHeat, Drought
Diseases, Quality
Michoacán: Rare allele hot spot
Gene Bank to Breeding Pipeline
Large-scale efforts to move useful gene bank diversity to breeding pipelines
Diversity profiles
Global wheat diversity in
process
GBS map
28K wheat GBS map
Trait donors
Donors for heat, drought, diseases & quality
Characterization
Large-scale germplasm
characterization
Core sets
Core set of wheat landraces
Novel alleles
New alleles for adaptive traits
LTP resource
Large scale prebreeding for impact delivery
GWAS
GWAS for heat, drought, diseases & quality
CIMMYT SeeD-Wheat: Genetic and Genomic Resources
Genomics of Gene Bank Accessions
Value of a gene bank resides in rare allelic variations and captured by high density genome sequencing
Rare allele variation in Mexican wheat landraces
Mexican landraces with grain yield advantge upto 250 g m-2 under heat stress (Cd. Obregón, México)
0
20
40
60
80
100
120
140
Early floweringLate floweringMedium flowering
Grain yield (g m-2)
Num
ber o
f acc
essi
ons
150 200 250 300 350 400 450
Control: Elite bread wheat (Sokoll), 186 g m-2
Exploring Gene Bank for Heat Tolerance
• Tolerant Mexican landraces (YELLOW)
• Tolerant Iranian landraces (RED)• Elite lines (BLUE & GREEN)
PCA
Association mapping for yellow rust in wheat landrace
Accession / Pedigree Yr (%) in Mexico Yr (%) in India
CHIH95.5.18 20 10
CHIH95.5.23 10 10
DGO95.3.8 20 10
OAX93.1.1.1 20 5
Susceptible check 100 100
Yellow rust resistant wheat landraces
Screening Gene Bank for Yellow Rust
Screening Gene Bank for Biofortification
Nu
mb
er o
f gen
otyp
es
Grain Zn concentration (ppm)
Evaluation for Zn content
GWAS for Zn content
8,000 advanced lines selected under heat, drought, and for plant type
Product ready for multi-location evaluation
Genetic populations to accelerate gene discovery
1000 Linked top cross populations Outcomes:
Wheat Prebreeding at CIMMYT
CIMMYT• Mexican landraces• Primary synthetics• Historical breeding
lines from CIMMYT
FIGSLandraces from:Iran, Iraq, Afghanistan, Pakistan, and IndiaICARDA
FIGS material screened at ICARDA for heat and drought tolerance
Prebreeding Populations: Exotics and Elites
AUSTRALIACollections from different parts of the world, adapted to hot environments of Australia
Elites: CIMMYT’s best 25 elite genotypesFIGS: Focus Identification Germplasm Strategy
General genetic diversity Functional diversity
Elites
Exotics (FIGS, Australian hot, primary synthetics)
Diversity Profiles of Gene Bank Accessions
Outcome: Panel of exotics crossed with multiple elites for developing bridging germplasm
Prebreeding Product for Breeding Pipelines
8K prebreeding lines selected after screening for heat, drought, input efficient and plant type
4,000 Topcross-derived fixed lines
Select 40% of the lines
Genotype and phenotype the training set, develop GS model
Apply GS model to lines
Remaining lines
Select lines with high GEBV and intercross
Make F2 and F3 populations
Identify lines with positive allelesValidate and advance
Product delivery in three years
LTPs: Resource for Genomics-assisted Breeding
Wheat Prebreeding: Path to Deliveryx
Segregating population
Screening in target environments - Mexico, South Asia, Africa
Introgress into breeding germplasm to develop varieties
CIM
MYT
NAR
S
El Batan Diseases, input useRusts, plant typeTolucaH, D, YieldObregon
Selection
FARMERS
Exoticssynthetics, landraces, FIGS
Elite
Cultivar developmentAt CIMMYT and
elsewhere
IWYP, HEDWIC
Yield potential; heat/drought
tolerance
DRRW, Harvest+
Rust, nutritional
quality
Genebanks
Geneti
c div
ers
ity
SeeDSystematically
mobilizing new Diversity
Partnerships with trait-specific projects: Population development
for genetic analysis and pre-breeding
Partnerships with genebanks: Germplasm characterization
SeeD-Wheat Synergies
Country-specific projects (WISP, BREADWHEAT)
Strategic researchGenomics, Phenomics
Summary and Path Forward Wide variation identified for agronomic and quality traits, as well
as disease resistance
More than 1,000 exotic accessions subjected to prebreeding
8,000 advanced germplasm lines ready for use in breeding pipelines
Trait donors identified and shared with the breeders for introgression into elite germplasm
GBS characterization of 50,000 +25,000 (CIMMYT+ICARDA gene banks) accessions completed and ready to be placed in public domain
Core collections of landraces available
Potential linkage being developed with NARS to deliver impact at farmers’ fields
We acknowledge CIMMYT researchers and collaborators for their contributions