Post on 03-Jan-2016
Durable Leaf Rust Durable Leaf Rust Resistance in WheatResistance in Wheat
J. A. KolmerJ. A. Kolmer
USDA-ARS USDA-ARS
Cereal Disease LaboratoryCereal Disease Laboratory
Puccinia triticina - Puccinia triticina - Wheat Leaf RustWheat Leaf Rust
Most common rust Most common rust of wheat in U.S.of wheat in U.S.
Occurs nearly Occurs nearly wherever wheat is wherever wheat is growngrown
Asexual in Asexual in North AmericaNorth America 50-60 races in U.S.50-60 races in U.S. Annual yield lossesAnnual yield losses
Leaf Rust Virulence Dynamics Leaf Rust Virulence Dynamics Kansas - NebraskaKansas - Nebraska
1978 1982 1986 1990 1994 1998 20020
10
20
30
40
50
60
70
80
90
100
Year
Lr1
Lr9
Lr24
Lr26
Lr11
Lr17
Lr10
U.S. Hard Red Spring WheatU.S. Hard Red Spring Wheat Wheaton (1983) Wheaton (1983) Lr10, Lr10, Lr23Lr23, Lr13, , Lr13, Lr34Lr34 +? +? Norm (1992) Norm (1992) Lr1, Lr10, Lr13, Lr1, Lr10, Lr13, Lr16, Lr23Lr16, Lr23, , Lr34Lr34 both highly resistance since releaseboth highly resistance since release
Alsen (2000) Alsen (2000) Lr2a, Lr10, Lr13, Lr23, Lr34 Lr2a, Lr10, Lr13, Lr23, Lr34 R-MRR-MR Knudson (2002) Knudson (2002) Lr3, Lr10, Lr13, Lr3, Lr10, Lr13, Lr16, Lr23, Lr34Lr16, Lr23, Lr34 Briggs (2002) Briggs (2002) Lr13, Lr13, Lr16, Lr30, Lr34Lr16, Lr30, Lr34 Both highly resistantBoth highly resistant Marshall (1982) Marshall (1982) Lr2a, Lr10, Lr13, Lr2a, Lr10, Lr13, Lr34Lr34 Mod. SusceptibleMod. Susceptible
Effective Effective LrLr genes genesin spring wheat cvs.in spring wheat cvs.
AlsenAlsen 2a,10, 13, 23, 342a,10, 13, 23, 34 5 -20 MR5 -20 MR
NormNorm 1, 10, 16, 23, 13, 341, 10, 16, 23, 13, 34 Trace RTrace R
KnudsoKnudsonn
3, 10, 16, 23, 13, 343, 10, 16, 23, 13, 34 Trace RTrace R
TcTcLr16Lr16 50 - 70 MS50 - 70 MS
TcTcLr23Lr23 5 - 10 R MR5 - 10 R MR
TcTcLr34Lr34 5 - 10 M5 - 10 M
ThatchThatcherer
50 - 80 S50 - 80 S
Lr16, Lr23, Lr34 common in spring wheat
South American LandracesSouth American Landraces
Americano 25e (1918) Americano 25e (1918) Lr3, Lr3, Lr16Lr16, , LrX1,LrX1,LrAPRLrAPR
Americano 44d (1918) 1-2 APR genesAmericano 44d (1918) 1-2 APR genes
THBJ FieldTHBJ Field Tc*2/Am. 25e Tc*2/Am. 25e LrAPRLrAPR ;2- 30 MRMS ;2- 30 MRMS Tc*2/Am.44d Tc*2/Am.44d LrAPR LrAPR ;23 20 M;23 20 M Tc*2/Am.44d Tc*2/Am.44d LrAPRLrAPR ;2- 20 ;2- 20
MRMSMRMS
U.S. Soft Red Winter WheatU.S. Soft Red Winter Wheat
Coker 9663 (1996) Coker 9663 (1996) Lr9Lr9, Lr10, Lr14a , Lr10, Lr14a
R-MRR-MR
Pioneer 26R61 (1999) Pioneer 26R61 (1999) Lr13, Lr14b, Lr13, Lr14b, Lr26Lr26
R-MRR-MR
Lr34Lr34 in U.S. Wheat in U.S. Wheat
Hard red spring wheatHard red spring wheat Minnesota Minnesota common 1966-mid 1990scommon 1966-mid 1990s FHB resistant cvs. lack FHB resistant cvs. lack
Lr34Lr34 South Dakota - South Dakota - few cvs. with few cvs. with Lr34Lr34 North Dakota - North Dakota - few cvs. with few cvs. with Lr34Lr34
TcLr34 Tc
Lr34 Lr34 in U.S. Wheatin U.S. Wheat
Soft red winter Soft red winter wheatwheat - old and new - old and new cvs.cvs.
- not present- not present
Hard red winterHard red winter wheat - very rarewheat - very rare
Western spring Western spring wheatwheat - not present - not present
TcLr34 Tc
CSIRO PCR MarkerTip die back
LrLr genes in U.S. Wheat genes in U.S. Wheat Seedling resistance genes Seedling resistance genes - lower ploidy relatives - lower ploidy relatives - common wheat- common wheat Virulent races arise quicklyVirulent races arise quickly Lr9, Lr16, Lr26 - still provide Lr9, Lr16, Lr26 - still provide
some resistancesome resistance Adult Plant GenesAdult Plant Genes Lr34 - not sufficient aloneLr34 - not sufficient alone Lr12 - ineffectiveLr12 - ineffective Lr13 - ineffectiveLr13 - ineffective Lr23 - characteristics of APRLr23 - characteristics of APR
Combinations of Lr34 + Combinations of Lr34 + effective seedling genes effective seedling genes
= best resistance= best resistance
TcLr34 TcLr13 TcLr12 Tc