Mapping leaf rust resistance genes in wheat
Jim KolmerUSDA-ARS Cereal Disease Laboratory
Jim AndersonUniv. of Minnesota
Thanks to Kun Xiao, Jen Flor
RL6149
RL6149 = Thatcher*6/T. turgidum 8404Developed by P. Dyck
RL6149 IT is ; (fleck) 20-50 MRMS
Thatcher x RL6149 F2
(: - 3) 100 (3+4) 30
F3 families
32 HR 63 Seg 25 HS
RL6149
F3 families used for mapping
6AL location – flanked by Barc104 (13.9cm) and GWM427 (21 cm)
No other Lr gene on 6AL
Designated as Lr64
RL6062RL6020 = Thatcher*6/ PI268316Developed by P. Dyck
PI268316 common wheat
RL6062 22+ IT 30-50 MRMS
Thatcher x RL6062 F2
(2-2+ ) 90 (3-4) 43
F3 families
26 HR 73 SEG 36 HS
Infection type F2
RL6062
Polymorphic SSR markers not linked to resistance gene
Bulk Segregation Analysis
15 HR 15 HS F3 families
8 DArT markers on 6BL in disequilibrium – distal region SSR data
Lr3 - Lr9 – linkage?
RL6062 isolate specificity different
P. L. Dyck - 1980
Americano 25eUruguay landrace derived1918 – highly resistant
Tc*2/Americano 25e F6
Adult plant resistance – no seedling resistance
10-20 MRMS field resistance0;2- adult plant IT greenhouse test
Tc*3/ Americano 25e F6 lines
Three field tests – greenhouse test
1-2 genes segregating
Severity (%)
Tc*3/Americano 25e F6 linesDArT map
Major effect on 1BL – likely Lr46
Select Tc*3 lines with Lr46 only
Tc*3/Americano 25e F6 lines
Smaller effect on 5B
No effect St Paul 2010 (fewer high severity lines)
Select Tc*3 lines with 5B QTL
Tc*3/Americano 25e F6 linesR2 values
Position StP 2009 StP 2010 Crk 2010 GH
1BL 26 0.254 0.293 0.392 0.379
28 (Lr46 mark)
0.257 0.303 0.382 0.409
30 0.263 0.299 0.381 0.411
32 0.265 0.292 0.373 0.408
34 0.264 0.281 0.362 0.399
36 0.259 0.266 0.346 0.386
38 0.251 0.248 0.325 0.367
5B
50 0.137 0.007 0.144 0.112
52 0.141 0.008 0.155 0.117
54 0.138 0.009 0.160 0.120
56 0.124 0.009 0.155 0.118