Meeting the Challenge of Yellow Rust in Cereal Crops - ICARDA

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In 2008 we monitored the CWANA-1st Stem Rust Resistance Spring Bread
Wheat Yield Trial. Monitoring these nurseries showed that 17 entries were
resistant to yellow rust diseases, with R-MR infection types; and 5 were
susceptible to yellow rust (Amir 1, Amir 2, Zafir 3, Borej 2 and Zain 2). There
are varieties with MS-S infection types. The four best lines of wheat for
productivity and resistance to rust diseases were selected for future breeding
purposes (Awahir 14, Durra 1, Durra 4 and Durra 5).
Table 2. Field responses to yellow rust in the Second International Yellow Rust Trap
Nursery (2nd IYRTN 2007–2008) in two ecological zones
Entry Cultivar and Yr Gene Heading Date
Chui
Field response
Issyk-Kul
33 Morocco (susceptible check) 16.05 40 MS 80 MS
19 Vilmorin 23(W), Yr3V 14.05 R 70 S
20 Moro, Yr10 25.05 R R (LR-80S)
21 Strubes Dickopf (W), YrSD 27.05 R MR
26 Kalyansona (S), Yr2 16.05 R R
37 Yr5/6*Avocet S, Yr5 18.05 R 60S
40 Yr8/6*Avocet S, Yr8 16.05 60S 80S
42 Yr10/6*Avocet S, Yr10 18.05 R R
43 Yr15/6*Avocet S, Yr15 16.05 R R
44 Yr17/6*AOC, Yr17 21.05 R 70S
Conclusion
Evaluation of rust diseases in 34 winter and facultative wheat varieties
released in Kyrgyzstan has shown 7 resistant (Azibrosh, Vinjett, Kasiet,
Krasnovodopadskaya 25, Zubkov, Kairak and Merim-MIS).
In Kyrgyzstan yellow rust is more harmful than other diseases under
irrigated and rainfed conditions. Monitoring in Chui region of Kyrgyzstan
indicated that the most effective genes against Puccinia were Yr2+, Yr4+, Yr5,
Yr10 and Yr15, expressing R-MR infection types. Virulence to Yr5 (Avocet) and
Yr17/6*(AOC) occurred in Issyk-Kul region, but not in Chui region. Avocet
isogenic lines Yr10 and Yr15 expressed resistant reactions to yellow rust under
field conditions in Chui and Issyk-Kul regions in the period 2006–2008.