Introgression lines of Triticum timopheevii in cultivated

Introgression lines of Triticum timopheevii in cultivated
wheat background and mapping of useful genes using
SNP markers
SCPRID (BBSRC and DBT 2013-2017)
Urmila Devi
Rationale
2050 – World’s population increase from 6 to 9 billion, thus food production needs to
increase by 70% over present levels
Climate change
Environmental change
Bioenergy change
BREEDERS
ChallengeTo develop superior adapted genotypes that meet the demands of increasing
global population
ObstacleLess Genetic variation available in modern wheat varieties for breeders
Increase Genetic Variation
Novel germplasm, including wild relatives of wheat (alien species) being
developed for breeding programmes
As , wild relatives has vast potential reservoir of genetic variation for:Abiotic and biotic stresses
Biomass
Yield
Photosynthetic potential
Rye
Triticum urartu
Aegilops speltoides
Thinopyrum bessarabicum
Objectives
Transfer small alien chromosome segments carrying target genes but
lacking deleterious genes into wheat quickly and efficiently
Hence, production, identification and evaluation of novel plant
phenotypes by introgression breeding
Achieved via exploitation of new marker technology, e.g., SNPs, to
detect and characterize wheat/alien recombinants
Triticum Timopheevii
•
•
•
•
Tetraploid wheat Triticum timopheevii Zhuk. (2n = 28, genome composition
AtAtGG).
Although T. timopheevii is morphologically similar to T. turgidum, it crosses
poorly with it and has a distinct Karyotype (Badaeva et al 1986; Gill and Chen
1987; Jiang and Gill 1994).
T. monococcum L. ssp. Urartu is generally accepted as the donor of the At and
A genomes of T. timopheevii and T. turgidum, respectively (Dvorfik et al 1993).
The B and G genomes are proposed to have originated from an S-genome
species, either Aegilops speltoides or a closely related ancestral form (Sarkar
and Stebbins 1956; Jaaska 1978; Chen and Gill 1983; Ogihara and Tsunewaki
1988).
Significance
• Excellent source of disease
resistance particularly
against rust pathogens.
• Rust resistance genes- Lr18
and Lr50
• Stem rust- Sr36, Sr37, Sr40
• Powdery mildew- Pm6,
Pm27, Pm37 (McIntosh et
al 2008)
• Carry other unknown genes
determining resistance to
fungal diseases.
Wild material screened by Paul Nicholson at JIC. Found the
Triticum timopheevii accession to be completely resistance to
Fusarium head blight
 Yield losses
Mycotoxin contamination
Wheat/ancestral introgression
- Recombinants
Wheat ph1/ph1
A
B
D
Wild relative (R)
X
Wheat
X
A
B
D
F1 hybrid
High throughput screening of BC1 and
subsequent backcross progeny to identify
recombinants
Selfing
Phenotyping
platform
Isolation of homozygous introgressions
The technology is now available
to exploit the distant relatives of
wheat
Wheat ph1/ph1
A
B
D
Wild relative (R)
X
Wheat
X
A
B
D
F1 hybrid
High throughput screening of BC1 and
subsequent backcross progeny to identify
recombinants
Selfing
Axiom® 35K array
Identify introgressions etc
+ KASP- used in later generations
Crossing Procedure
BC1 seeds
BC2 seeds etc
Seed sterilization
Shrivelled grain culture – dry grains
Vernalisation (6 weeks)
Different accessions of wheat /mutant x Triticum timopheevii
(BC2 plants and BC1 plants )
•Chinese spring
•Paragon
•Chinese spring mutant
•Paragon mutant
BC3 , BC2 Seeds + Selfed seeds
Shrivelled grain culture – growing plants
Producing new F1s
Female
Wheat mutant
(2n=6x=42;AABBDD)
x
Pollen donor
Triticum timopheevii
(2n=4x=28;A’A’GG)
F1 hybrid
(AA’BGD)
F1 hybrid
(AA’BGD)
x
BC1
P95-99.1-1
Wheat mutant
(AABBDD)
x
Wheat mutant/Normal Wheat
Screening with SNPs for
ph1/ph1
355452
BC2
289752
538512
Screening for Introgressed
segments
Chinese
Spring (F)
BC1-384B
(M)
BC2-372A
(M)
Number of Seed’s Produced
S. No.
Accessions
Name
F1’s
BC1’s
BC2’s
BC3’s
BC4’s
1.
P95-99.1-1#
35
111
1408
5855
2691
2.
289752
76
*
*
*
*
3.
355452
18
52
*
*
*
4.
427414
21
*
*
*
*
5.
427998
8
*
*
*
*
6.
538512
13
*
*
*
*
# Resistant to Fusarium Head Blight (FHB)
Wild accessions of Triticum timopheevii
538512
289752
355452
P95-99.1-1
DNA of BC1, BC2, BC3 genotypes used for
crossing was sent to Bristol for primer
validation and genotyping
(Keith Edwards)
BC1- 194
BC2- 268B
Marker AnalysisFlapjack
JoinMap
Visualization- GGT2 (Graphical
Genotypes)
BC3- 105A
BC1- 304
BC3- 113A
BC2- 276C
Marker AnalysisFlapjack
JoinMap
Visualization- GGT2 (Graphical
Genotypes)
Mineral Analysis- Seed Data
Mg
Zn
S
P
Fe
(mg/kg)
(mg/kg)
(mg/kg)
(mg/kg)
(mg/kg)
Paragon wheat
967.55
19.77
1267.11
3848.36
28.04
Paragon wheat
965.37
20.12
1302.22
3881.42
31.51
Paragon wheat
913.14
19.49
1250.03
3746.70
28.02
Paragon wheat
996.91
23.42
1324.42
4068.71
38.26
Paragon wheat
1031.78
23.29
1428.46
4122.43
32.52
Paragon wheat
876.91
19.74
1094.18
3451.65
25.76
Paragon wheat
1127.10
25.58
1542.55
4520.96
30.18
Paragon wheat
857.75
18.46
1172.04
3443.57
24.35
T timopheevii P95-99.1-1
2202.27
87.63
2245.40
7055.43
58.54
T timopheevii 538429
2866.71
90.01
3058.48
8374.64
49.96
T timopheevii 427998
2721.44
115.39
3258.69
7602.36
53.88
T timopheevii 355452
2730.12
95.22
3185.88
8512.85
66.28
T timopheevii 427414
2418.21
57.81
2472.82
6824.54
28.39
T timopheevii 538512
3024.73
156.14
3678.32
9314.95
76.53
T timopheevii 289752
2141.79
80.44
2877.26
6500.29
32.74
Future Prospective
• All the plants in segregating generations will be analyzed with markers
(SNPs) .
• Plants homozygous for ph1b mutant and having introgressed segments
from T. timopheevii will be identified.
• A set of homozygous introgression lines representing whole of T.
timopheevii genome will be developed.
“ All the chromosome segmental substitution lines for A and G genome of T.
timopheevii will be genotyped and phenotyped for target trait using SNP markers
which will result in the mapping of new genes from T. timopheevii”
King’s Group
Ian and Julie King
Csilla Nemeth
Surbhi Mehra
Caiyun Yang
Stella Edwards
Paul Kasprzak
Duncan Scholefield
Stephen Ashling
Jonathan Atkinson
Paul Waldron
Jason Rayner
Urmila Devi
Thanks