This document summarizes a project to improve sorghum productivity in Mali through an integrated Marker-Assisted Recurrent Selection (MARS) approach. The project phenotyped multiple traits across multiple environments to identify favorable alleles and define ideal genotypes. It conducted several breeding cycles and genotyped populations to detect QTLs. The main products were improved sorghum material and capacity building activities. Key lessons included validating MARS for African sorghum breeding and considering different trait combinations for varying environments.

1. Improving sorghum productivity in
semi-arid environments of Mali
through integrated MARS
G4008.48
Products, challenges & lessons learned
J-F Rami – General Research Meeting – Lisbon – 27th - 30th Sep 2013

2. MARS: increase the exploration of recombination
potential in bi-parental population
Breed for :
multiple traits
polygenic traits
diverse environments...
...Towards an ideal genotype
cumulating favourable alleles
from both parents for all genes
involved in different target
traits
X
Parent 1 Parent 2
X
Parent 1 Parent 2
GV GV GV GV GV GV GV GV GVGV GV GV GV
QTL detection
Multiple traits
Multiple
environments
GV

3. Lata3 KeninkeniTiandougouX X
Parents chosen for MARS are elite varieties with
complementary traits
Guinea type
Medium size
Photoperiod sensitive
Tillering
Caudatum type
Short size
Photoperiod sensitive
High productivity
GC type
Medium size
Photoperiod sensitive
Good grain quality
400 F3 400 F3

4. The project in a
nutshell
Keninkeni Lata3
Population 114 Population 118
x x
F4 Families
(10 plants)
…
…
F4 seed increase (F5 Bulk)
Phenotyping
3 sites x 2 sowing dates
1 site for grain quality
F1
F2
F3
S2
S3
S4
Dec. 2008
March 2009
June 2009
F4 Families
(10 plants)
Dec. 2009
Feb. 2010
QTL analysis
Ideotype definition
Phenotyping
3 sites x 2 sowing dates
1 site for grain quality
F3 genotyping
QTL analysis
Ideotype definition
Genotyping
C1 cycle (F4 families)
C1 genotyping
C1 crosses
June 2010
Jan. 2011
June 2011
Jan. 2012
C1 seed increase
(F2)
June 2012
C1
evaluation
(F3)
Tiandougou
C2 seed
increase (F2)
C1 + C2 evaluation
(F2)
Jan. 2013
June 2013
C1 cycle (F4 families)
C1 genotyping
C1 crosses
C2 cycle (C1 families)
C2 genotyping
C2 crosses
C3 cycle
(C2 + C1 families)
C3 genotyping
C3 crosses
F4 seed increase (F5 Bulk)
June 2008
F1
F2
F3
S2
S3
S4

5. • 3 locations : Sotuba, Cinzana, Farako
• 2 sowing dates in each location
• Multiple traits
• Yield and components
• Flowering date
• Plant morphology
• Panicle morphology and architecture
• Grain quality (NIRS + mini Tô)
Challenges: multilocation phenotyping

6. Challenges: multilocation phenotyping

7. Grain yield
Grain quality
Grain quality
Grain yield
Challenges: QTL detection and ideotype
definition

8. Challenges: Genotyping data management
Track inconsistent genotyping data in pedigrees
• Identify:
• Wrong crosses
• Selfing
• Very short
timeframe

9. Challenges :
From crosses ranking to crossing

10. Keninkeni Lata3
Population 114 Population 118
x x
…
F4 seed increase (F5 Bulk)
Phenotyping
3 sites x 2 sowing dates
1 site for grain quality
F1
F2
F3
S2
S3
S4
Dec. 2008
March 2009
June 2009
Dec. 2009
Feb. 2010
QTL analysis
Ideotype definition
Phenotyping
3 sites x 2 sowing dates
1 site for grain quality
F3 genotyping
QTL analysis
Ideotype definition
Genotyping
C1 cycle (F4 families)
C1 genotyping
C1 crosses
June 2010
Jan. 2011
June 2011
Jan. 2012
C1 seed increase
(F2)
June 2012
C1
evaluation
(F3)
Tiandougou
C2 seed
increase (F2)
C1 + C2 evaluation
(F2)
Jan. 2013
June 2013
C1 cycle (F4 families)
C1 genotyping
C1 crosses
C2 cycle (C1 families)
C2 genotyping
C2 crosses
C3 cycle
(C2 + C1 families)
C3 genotyping
C3 crosses
F4 seed increase (F5 Bulk)
June 2008
F1
F2
F3
S2
S3
S4
Main product:
improved material
724 F4 Plants (20 Families)
140 SNP
130 C1 crosses
105 Selfing
647 C1 Plants (23 Families)
140 SNP
125 C2 crosses
70 Selfing
558 C2 Plants
(19 C2 Families + 13 C1 families)
150 SNP
20 C3 crosses
60 Selfing
760 F4 Plants (30 Families)
158 SNP
Crosses starting in two weeks
Population 114 Population 118

11. Main product: improved material
P114 Pedigree
Alelles selection over cycles
Evolution of index value over cycles
P114 – C1
Phenotyping
Evaluation
2 locations x 2 reps x
2 sowing dates

12. Strategy for variety development
Year Type Sub type
Nb of
entries Nb of Rep Nb of envt Nb of Plot Designation
2013 Screening trials Station 64 2 6 768 C2P114
2013 Variety trials Station 6 4 3 72
2013 Variety trials Farmers 10 1 30 300
2014 Screening trials Station 64 2 6 768 C1P118
2014 Screening trials Station 64 2 6 768 C3P114
2014 Variety trials Station 10 4 3 120
2014 Variety trials Farmers 10 1 30 300
2015 Screening trials Station 64 2 6 768 C2P118
2015 Variety trials Station 15 4 3 180
2015 Variety trials Farmers 10 1 30 300
2016 Screening trials Station 64 2 6 768 C3P118
2016 Variety trials Station 20 4 3 240
2016 Variety trials Farmers 10 1 30 300
2017 Variety trials Station 25 4 3 300
2017 Variety trials Farmers 10 1 30 300

13. Products: Grain quality phenotyping
• Improvement and transfer
to IER of NIRS calibrations
• Protein content
• Lipid content
• Amylose content
• Endosperm texture
• Grain image analysis
Grain roundness Grain color
Diarah
Guindo

14. Capacity building
• Two PhD students:
• Dramane Sako (Mali) – Genetics of panicle
architecture
WACCI – Ends early 2014
• Diarah Guindo (Mali) – Genetics of grain quality
End Oct 2014
• Two MSc students:
• Korotimi Thera – Flowering and photoperiod
sensitivity modelling and genetics
• Mohamed Tekete – Flowering time in BCNAM
populations
• All part of the IBP Multi Year Course

15. Lessons learned
MARS proof of concept: a valid procedure for
sorghum breeding in Africa.
• Pitfall: “eggs in same basket” approach
• Broad genetic basis: some genes with large effect
• Multiple traits, multiple environments
• Relations between traits, differential expression of
QTLs in various environments.
• Break some possible antagonisms between traits,
test different hypothesis, design various ideotypes
for various environments..

16. Summary
• Successful integration of : - Methodology
- Tools/services
- Capacity Building
into sorghum national breeding programme in Mali
• Extensive evaluation to come toward variety
development
• Significant change in the way of conceiving/conducting
breeding
• Capacity building

17. Baptiste Guitton
Elodie Lacut
Michel Vaksmann
Jean-Francois Rami
Denis Lespinasse
Michel Ragot
IER
Niaba Témé
Mamoutou Kouressy
Sidy Bekaye Coulibaly
Flakoro Coulibaly
Yacouba Dembélé
Mohamed Doumbia
Mahamady Kané
Korotimi Thera
Dramane Sako
Diarah Guindo