Transcript 3+ 3 - NVT Online

Genetics of new sources of rust
resistance, backcrossing in wheat &
overseas testing for stem rust
Harbans Bariana
Genetics – APR to stem rust
Burrion (Sr31+APR)/LB - Two APR genes in Kenya
AWCC993/Yitpi - Monogenic segregation
AWCC1141/Yitpi - Monogenic segregation
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Genetics – APR to leaf rust
Genetic analysis of two landraces showed digenic
segregation
Monogenically segregating populations (MSPs) were
isolated
Five MSPs are confirmed and genomic location
studies are in progress
Two gene segregation was noted in Sonora/BT
Schomburgk (BTS) population. One slow rusting
minor gene is contributed by Sonora and a major
gene is contributed by BTS
Monogenic segregation for an APR gene from
Westonia was noted in a cross made for stripe rust
resistance analysis
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Genetics –APR to stripe rust
Trigenic segregation in Sonora/BT Schomburgk (BTS)
population. Sonora appear to contribute one race-specific
and one APR gene. One APR is contributed by BTS
BC1F2 analysis of Wollaroi/2*NYB3 cross
confirmed segregation of 3 to 4 genes for
adult plant stripe rust resistance
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Genetics –Seedling resistance
stripe rust
A new widely effective gene for stripe rust
resistance was shown to be linked closely
in repulsion with Yr4
Genetic analysis based on Frelon/NYB3
F3 population demonstrated the presence
of one more gene in addition to Yr17
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Genetics – Durum wheat
Wollaroi showed infection type 23n to 3n in the seedling stage.
This phenotype segregated with Qyr.sun-2A which explains 9 to
12% phenotypic variation. Request to name this locus has
been sent to Bob McIntosh. It is likely to be named Yr56.
Identified new sources of resistance against durum leaf rust
pathogen, populations are being developed.
An F5 population of a durum genotype carrying APR to stem
rust will be phenotypes in 2013
Tamaroi/Bansi F6 population showed monogenic segregation
for leaf rust resistance against wheat leaf rust pathogen
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Triple rust resistant donor
development through backcrossing
Yr40/Lr57 – Five backgrounds
Lr49,Lr13, Lr34 - four backgrounds
 Yr47/Lr52 – Four backgrounds
 Yr35/Lr53 – Five backgrounds
 Lr67/Yr46/Sr55 – Three backgrounds
 Yr49 – Initial crosses made in four backgrounds
 Yr37/Lr54 – Initial crosses made
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Amelioration of donors
 Sr50 - it was highly susceptible to stripe rust and has been
crossed with Yr40/Lr57 and Yr47/Lr52
 Yr49 - It was highly susceptible to leaf rust and stem rust. It
has been crossed with lines leaf rust and stem rust resistant
donors
 Yr34 - It is also being improved for leaf rust and stem rust
resistance
 Sr39 (shortened segment ) has possibly lost leaf rust
resistance and it was crossed to top up leaf rust resistance
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Ug99+Sr24 Screening
Bullet, Cadoux, Condor , Clearfield JNZ, Dakota , Gabo,
Gamenya, GBA Sapphire, Janz, Kidman, Meering, Mitre, Petrie,,
Waagan, – Sr28 type resistance
,
Bolac, Crusader, Carinya , EGA Wentworth - Other than Sr28
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Potential threats
› Durum leaf rust races
› Ethiopian and Indian stem rust races
- (Sr13 virulence)
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Response to American leaf rust
pathotypes
Bellaroi
Caparoi
Gundaroi
Hyperno
Jandaroi
Saintly
Kalka
Tjilkuri
WID802
WID803
Wollaroi
Yallaroi
Tamaroi
Kamilaroi
CA 1.2
3+
3+
3+
3+
3+
3+
3+
3+
3+
3+
3+
33+
3-
09 AZ 103 A
;
;
;
;
3;
;
;
;
3+
;23+
3+
;1-
THBJ
;
;
;
;1;
;
;
;
3+
;
3;1;
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Kenya - Ug99+Sr24
Genotypes
14
9
5
1
3
14
B04-17
Bellaroi
Caparoi
Hyperno
Jandaroi
Kalka
Saintly
Tamaroi
Tjilkuri
Wollaroi
Rust response
2
3
4
5
6
seg
65
67
5,3,2
2,45
34
23,5
3
5,3
23,4
5
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Ethiopia - Sr13 virulence
Genotypes
2
16
29
7
5
Arrivato
Bellaroi
Caparoi
Gundaroi
Hyperno
Jandaroi
Kalka
Kamilaroi
Saintly
Tamaroi
Tjilkuri
WID802
WID803
Wollaroi
Yallaroi
Rust response
5
6
7
8
seg
5 TO 6
67
67
7
6
5
67
7,5
6
7
67
67
56
5E, 78L
7
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Summary
 Focus is to characterize APR genes other than
known
 Facilitate release of triple rust resistant varieties
for growers through provision of resistance
donors
 National and international training
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Thank You
IARI RRS, Wellington, India
KARI, Njoro, Kenya
Ug99+Sr24
40A – Sr24
PBI,
Cobbitty,
Australia
98-1,2,3,5,6,.7+34-1,2,7+Sr38
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