Seedling and adult plant reaction of some promising wheat lines to yellow rust

Yellow (stripe) rust caused by Puccinia striiformis f. sp. tritici is an important disease that threatens wheat production worldwide. Host resistance is the most economical strategy to manage wheat stripe rust. For this purpose، 18 promising wheat lines of moderate zone were evaluated against yellow rust in Ardabil in order to determine their resistance level. The seedling reaction was evaluated in greenhouse by using race 6E150A+، Yr27. Adult plant resistance was also evaluated by measuring of final rust severity (FRS) and coefficient of infection (CI) under field infection conditions with two times artificial inoculations. Artificial inoculation was carried out using yellow rust race population virulent resistance genes including Yr2، Yr6، Yr7، Yr9، Yr22، Yr23، Yr24، Yr25، Yr26، Yr27، YrA، and YrSU. Field evaluation was conducted based on randomized complete block design with three replications during 2011-2012 cropping season at Ardabil Agricultural Research Station (Iran). Results showed that lines M-90-13، M-90-15، M-90-18 along with susceptible check (Bolani) had the highest values of FRS and CI. The lines M-90-2، M-90-4، M-90-5، M-90-7، M-90-8، M-90-13 and M-90-17 were susceptible at the seedling stage and had low level infection at the adult plant stage. Consequently، these lines had different levels of durable resistance based on the results of this investigation and their pedigree information. The remaining lines that had low level of infection at the seedling and adult plant stages were selected as moderately resistant or resistant lines.