밀 줄기녹병 저항성 유전·육종 주요 연구동향

Research Advances in Wheat Breeding and Genetics for Stem Rust Resistance

Stem rust is a major wheat disease caused by the fungus Puccinia graminis f. sp. tritici (Pgt). Occurring mainly in warm and humid climates, stem rust has generally been considered less prevalent than leaf rust (P. triticina) and stripe rust (P. striiformis f. sp. tritici). However, a highly virulent stem rust race, Ug99, appeared in Uganda in 1998 and has devastated wheat production throughout Africa and the Middle East. As damage caused by the Ug99 lineage and other newly diverging stem rust races continues to increase, extensive research on wheat breeding and genetics to enhance stem rust resistance has been conducted internationally. Among the 60 stem rust resistance genes reported thus far, 11 (Sr13, Sr21, Sr22, Sr33, Sr35, Sr45, Sr46, Sr50, Sr55, Sr57, and Sr60) have been cloned. New resistance sources have been sought by screening diverse wheat germplasms through international collaborations. Such efforts are urgently required in Korea to address the increasing threat of stem rust epidemics. Furthermore, major Pgt races in the Korean peninsula need to be pathotyped. This information can be used to screen major wheat cultivars, breeding lines, and landraces to identify effective resistance sources. Previously reported stem rust resistance genes should also be introduced and pyramided into the genetic background of Korean wheat breeding populations via available molecular markers. Finally, research capacity in molecular genetics and genomics needs to be strengthened to enable the identification of new stem rust resistance genes and the development of precise molecular markers.