Thirty-three promising barley lines, obtained from SPII, along with susceptible check were studied to assess their resistance to yellow rust. Adult plant resistance were evaluated by measuring of final rust severity (FRS), and coefficient of infection (CI) under natural infection conditions with once artificial inoculation during 2010 - 2011 cropping season in field plots at Ardabil Agricultural Research Station (Iran). Artificial inoculation in field was carried out by yellow rust inoculum having virulent genes against rps2, Rps1.b and Topper. Results showed that lines EBYTC-88-1, EBYTC-88-11, EBYTC-89-13, EBYTC-89-14 along with susceptible check had the highest values of FRS and CI, therefore were selected as moderately susceptible to susceptible lines. The lines EBYTC-88-4, EBYTC-88-5, EBYTC-88-9, EBYTC-89-3, EBYTC-89- 5, EBYTC-89-6, EBYTC-89-7 and EBYTC-89-19 had low level infection at adult plant stage. Consequently these lines with low values of CI and FRS at adult plant stage most probably have partial resistance.
