Meeting the Challenge of Yellow Rust in Cereal Crops - ICARDA

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Yellow rust of wheat in Ethiopia:
its importance in a regional context
Ayele Badebo, 1 H. Fehrmann 2 and A. Yahyaoui 3
1. Ethiopian Agricultural Research Organization (EARO), Addis Ababa, Ethiopia
2. Institute of Plant Pathology and Plant Protection, Georg-August-University,
Germany; 3. ICARDA, Aleppo, Syria
Yellow [stripe] rust caused by the fungus Puccinia striiformis Westend. f.sp.
tritici is one of the most threatening wheat diseases in Ethiopia. Monitoring
virulences and inventorying resistance genes in the country and in the region
will help to plan for appropriate gene management strategies. Since 1998,
yellow rust races from Ethiopia have been analysed in Goettingen, Germany,
and Kulumsa, Ethiopia, following standard procedures. Moreover, a trap
nursery comprising standard yellow rust differentials, commercial cultivars
and advanced lines from Ethiopia, Kenya and Yemen were sown at four
locations in Ethiopia during 2002/03.
According to the greenhouse and field studies, virulences for Yr4, Yr5, Yr10,
Yr15 and Yr17 are lacking in major bread wheat producing regions in Ethiopia.
Despite the susceptibility of Avocet-Yr1 under field conditions, virulence for
Yr1 (Chinese 166) has not been detected in greenhouse tests. Virulence for
Yr3V (Vilmorin 23) was detected for the first time in 2002. The multi-location
resistance test indicated that almost all of the commercial cultivars from
Yemen and Ethiopia were susceptible at least one of the locations. A high level
of yellow rust resistance was observed in some of the Kenyan bread wheat
cultivars, and in newly developed bread wheat lines from Ethiopia. The
commonalities of yellow rust races among the East African countries and
Yemen have often been reported. Therefore, the information generated from
this study would be of paramount importance for researchers in the region to
anticipate threatening virulences.