Rapid spread of a virulent race of stem rust of wheat has increased interest in looking
different source of resistance. This investigation was carried out to identify possible
sources of resistance in Ethiopian commercial wheat cultivars to the current stem rust race,
UG99. 23 bread and 14 durum wheat cultivars were evaluated in two different sets. A
standard bread wheat cultivar PBW343 (Sr31) as well as Morocco and Arendeto were
included as susceptible checks. In seedling test, plants were inoculated with pure TTKS race
and evaluated for their infection types. In field test, a 5 x 5 and 4 x 4 simple lattice design
was used to evaluate bread and durum wheat cultivars respectively. Each block was
separated by the spreader row composed of PBW343 and Morocco in a 3: 1 ratio. In order to
create epidemics, natural infection was supplemented artificially by inoculating the spreader
rows at different growth stages. Area under Disease Progress Curve (AUDPC) was
calculated and analyzed. Coefficient of Infection (CI) was calculated by taking the severity of
stem rust and response. Terminal severity of the cultivars was also considered for
comparison. In the seedling test, all of the durum except Arendeto, Foka and Kilinto were
resistant. However, most of the bread wheat cultivars were susceptible. Similar results were
obtained in the field screening of wheat cultivars at Debre Zeit, an international known hot- spot for stem rust of wheat. The identified sources of resistance in some bread and most
durum wheat will serve as source in breeding programs for resistance to stem rust of wheat.
Attempts should also be made to transfer stem rust resistance from durum to bread wheat
as a valuable component of breeding strategy that will contribute to sustainable production
of the crop. Furthermore, it is essential that the identified resistant wheat cultivars be
evaluated against dominant stem rust races in different wheat growing areas of the country.