11-14 February 2019. Jodhpur, India. The 13th International Conference on Dryland Development Presentation of Michael Baum for Filippo M Bassi Director Biodiversity & Crop Improvement Program

1. International Center for Agricultural Research in the Dry Areas
icarda.org cgiar.org
A CGIAR Research Center
Durum wheat ideotype for the drylands of
tomorrow
Michael Baum for Filippo M Bassi
Director
Biodiversity & Crop Improvement Program

2. icarda.org 2
Getting ready for a 4 ⁰C warmer World
10 years
Arab climate change assessment report 2017:
• +1.9 ⁰C by 2050
• +4.8 ⁰C by 2100
• -100 mm rainfall by 2100
• Doubling of days >40 ⁰C
• Decreasing of underground water
More droughts, more heat waves, shorter
growing seasons, new damaging pests
30 years

3. icarda.org 3
Is there an ideotype for climate change?
1. More droughts - drought tolerance is a complex trait that requires:
• Stability (GxE)
• Larger grain size via deeper roots
• More biomass
2. More heat waves: heat tolerance is also complex and it requires:
• Stability (GxE)
• Higher spike fertility
• More biomass
3. Shorter growing seasons: this is easier and it requires basically one trait:
• Early flowering
4. Damaging pests and disease:
• Rusts (stem and leaf)
• Septoria and tan spot
• Crown rot
• Hessian fly

4. icarda.org 4
Drought tolerance: stability
• The use of stability indexes to parsec GxE effect is a good way to determine stability
• Pairing GxE with G (BLUP) ensures ideal selection
• From the cover of Crop Science: durum international nursery tested in 25 environments in 18
countries for IDYT38th
Adaptation and stability analysis of ICARDA durum wheat elites across 18 countries
Bassi & Sanchez-Garcia. Crop Science (cover), 57:2419

5. icarda.org 5
GWAS for grain yield and yield stability (G + GxE)
• 280 modern lines genotyped with 35K Array
• 21 environments, from driest to most favorable
3 MTAs (2B, 5A, 5B) unique to stability and yield under
drought.
Drought prone environments Favorable environments

6. icarda.org 6
Drought tolerance: larger grains using roots
• Deep roots under drought explain up to 50% of the grain yield variation (r2)
• Three QTLs controls root angel and together increase yield +300 Kg ha-1
Root System Architecture and Its Association with Yield under Different Water Regimes in Durum Wheat
El Hassouni et al. Crop Science 2018, 58:1-16
r2
GYM
archouch
GYKfardan
TKW
M
archouch
TKW
Kfardan
Seedling root angle 0.01 0.46 0.04 0.03
Adult root angle 0.35 0.14 0.00 0.17
Ratio deep roots 0.46 0.50 0.21 0.05
Ratio shallow roots 0.22 0.14 0.02 0.06

7. icarda.org 7
Heat tolerance: spike fertility
• Application of plastic tunnels at the time of flowering
• >10 C increase in temperatures
• Grain yield, Grain.spk, Harvest index , Biomass significantly
affected, but not flowering time or grain size

8. icarda.org 8
Heat tolerance: GWAS for spike fertility
Locus Chr. Trait
QTL.ICD.Heat.01 1A GNspk, HI, TOL-GY
QTL.ICD.Heat.09 5B GNspk, SSI-GY, TOL-GY
QTL.ICD.Heat.10 6B GNspk, HI, GY, Biom, SSI-GY
QTL.ICD.Heat.02 1B GNspk, HI
QTL.ICD.Heat.06 3B GNspk, HI
QTL.ICD.Heat.12 7A GNspk, HI
• GNspk = spike fertility
• 3 MTAs identified only in plastic tunnel exp.
• 3 MTAs overlap with Senegal River test
• Yield differences under severe heat could be
observed for different haplotype

9. icarda.org 9
Flowering time to adapt to shorter seasons
• Association mapping panel was tested in 14 environments
globally to generate differences in flowering
• Clustered in 4 Phenological Mega Environments

10. icarda.org 10
Flowering time to adapt to shorter seasons
• Three major loci previously unknown in
durum wheat reduce the time to flowering
across all Phenological Environments
PhE1 Morocco
PhE2 Lebanon PhE4 Summer
PhE3 Senegal River

11. icarda.org 11
Damaging pests and diseases
Otb4/Caparoi
Otb4/Yawa
Otb4/Fadda98
R S
Crown rot + LR
• The true challenge is not to find resistances, but to combine them

12. icarda.org 12
Combining diseases resistance
• 280 elites and 96 landraces were tested at 24 disease environment for leaf rust, yellow rust,
Septoria and tan spot
• Only 3 lines from ICARDA combined resistances against all 4 diseases
• Septoria and tan spot are very challenging for durum wheat
• Each combination of disease resistance needs to be targeted for a specific agro-ecology
Zeina4
Bicrederaa
Ombar

13. icarda.org 13
Validation of QTLs via KASP
• All identified QTLs by GWAS are converted to KASP
• Validation is done on elite germplasm
• 15 explain >10% of the variation for grain yield under heat or drought
Correlationtophenotype
ValidatedforHessianflyValidatedforSenegalRiver

14. icarda.org 14
The Global Durum Panel (GDP)
• Seeking the help of the whole community: it was derived from 3,700 entries obtained from
21 partners in 19 countries
• It represents all the association mapping panel of durum wheat
• In 2018 1000 lines were shipped by ICARDA to 32 partners in 29 countries

15. icarda.org 15
One global crossing block
• Order the seeds at: http://indms.icarda.org/
• Get the 90K Illumina data from Gigwa
• Do your favorite phenotyping
• Run GWAS
• Publish
• Tell the durum community
• Validate to KASP
New alleles are
rapidly exchanged to
save durum from
Climate Change

16. icarda.org 16
Combining QTLs for heat and drought
• KASP markers validated from QTLs to define the expected performances of 22 F4 segregating populations
• Creating a molecular ideotype by combining useful haplotypes
Heat prone environments Drought prone environments

17. icarda.org 17
Going beyond MAS: Genomic Selection
• GS14: Genomic selection was used to select F4 lines, then advanced by normal breeding to F6
• These were put in competition against genebank material (GRS), speed breeding (QAF), and normal
breeding (ICD12-14-15), in 1 location preliminary yield trials, plots of 5m2.
GS was the most successful
Top yield

18. icarda.org 18
Conclusions
• Very difficult to define 1 ideotype for adaptation to climate change, they are several
• The use of GWAS followed by marker validation represent a strategic way to incorporate
complex phenotyping into breeding selection.
• With the help of the whole durum community we will be able to move faster to exchange
alleles and linked markers
• This opens the possibility for the creation of molecular ideotype
• Genomic selection could let us go beyond the need for MAS validation, and hence
accelerate the cycle

19. icarda.org 19
Thank you