View
215
Download
1
Category
Tags:
Preview:
Citation preview
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
2
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
3
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
4
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
5
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
6
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
7
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
8
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
9
Potential threats
› Durum leaf rust races
› Ethiopian and Indian stem rust races
- (Sr13 virulence)
10
Response to American leaf rust pathotypes
CA 1.2 09 AZ 103 A THBJBellaroi 3+ ; ;Caparoi 3+ ; ;Gundaroi 3+ ; ;Hyperno 3+ ; -Jandaroi 3+ 3- ;1-Saintly 3+ ; ;Kalka 3+ ; ;Tjilkuri 3+ ; ;WID802 3+ ; ;WID803 3+ 3+ 3+Wollaroi 3+ ;2- ;Yallaroi 3- 3+ 3-Tamaroi 3+ 3+ ;1-Kamilaroi 3- ;1- ;
11
Kenya - Ug99+Sr24Genotypes Rust response14 29 35 41 53 614 segB04-17 65Bellaroi 67Caparoi 5,3,2Hyperno 2,45Jandaroi 34Kalka 23,5Saintly 3Tamaroi 5,3Tjilkuri 23,4Wollaroi 5
12
Ethiopia - Sr13 virulenceGenotypes Rust response2 516 629 77 85 segArrivato 5 TO 6Bellaroi 67Caparoi 67Gundaroi 7Hyperno 6Jandaroi 5Kalka 67Kamilaroi 7,5Saintly 6Tamaroi 7Tjilkuri 67WID802 67WID803 56Wollaroi 5E, 78LYallaroi 7
13
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
14
Thank You
15
IARI RRS, Wellington, India KARI, Njoro, Kenya
PBI, Cobbitty, Australia
98-1,2,3,5,6,.7+34-1,2,7+Sr38
40A – Sr24
Ug99+Sr24
Recommended