عنوان مقاله [English]
Stem rust of wheat caused by Puccinia graminis f.sp. tritici, the most important disease of wheat in the past, is currently a potential threat to wheat production. The present research was conducted to determine the reaction of 38 elite lines of temperate agro-climate breeding program including 20 lines obtained from this program in 2015 (ERWYT-M-94) and 18 lines from 2016 (ERWYT-M-95) at seedling and adult-plant stages. Investigating seedling stage resistance was carried out by determining the reaction of experimental lines to three common races of Kelardasht, Mazandaran and one Ug99 race from Shavour, Khouzestan in the greenhouse. Investigating adult-plant resistance was carried out under field conditions in Kelardasht during two cropping years of 2015-16 and 2016-2017 for ERWYT-M-94 lines and two cropping years of 2016-2017 and 2017-2018 for ERWYT-M-95 lines. Results showed that the experimental lines had different reactions to disease at both seedling and adult-plant stages. At the seedling stage, the most lines with low infection type (resistance) were observed against the isolate 94-15 (race PTRTF), followed by the isolates 94-32 (race TTTTF), 95-95 31 (race TKTTF), and 2-95 (race TTKTK). In terms of adult-plant resistance, most of the lines had a lower disease rate compared to the susceptible check, and among them four lines of M-94-2, M-94-5, M-94-15 and M-94-16 from ERWYT-M-94 and three lines of M-95-2, M-95-9 and M-95-15 from ERWYT-M-95 were less susceptible compared to other lines. The reason for this could be the presence of adult-plant resistance genes in these lines.