Author
KUMSSA, TADELE - University Of Nebraska | |
BAENZIGER, P - University Of Nebraska | |
Rouse, Matthew | |
GUTTIERI, M - University Of Nebraska | |
DWEIKAT, I - University Of Nebraska | |
Brown-Guedira, Gina | |
Williamson, Sharon | |
Graybosch, Robert | |
WEGULO, S - University Of Nebraska | |
LORENZ, A - University Of Nebraska | |
POLAND, JESSE - Kansas State University |
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/1/2014 Publication Date: 1/1/2015 Citation: Kumssa, T.T., Baenziger, P.S., Rouse, M.N., Guttieri, M., Dweikat, I., Brown Guedira, G.L., Williamson, S.M., Graybosch, R.A., Wegulo, S.N., Lorenz, A.J., Poland, J. 2015. Characterization of stem rust resistance in wheat cultivar 'Gage'. Crop Science. 55:229-239. Interpretive Summary: Wheat stem rust is a fungal disease of wheat that decreases yield. A strain of the wheat stem rust fungus known as Ug99 emerged in Uganda in 1999 and threatens global wheat production because it is able to infect nearly all wheat varieties. United States hard red winter wheat cultivar Gage is resistant to Ug99. In order to facilitate the use of resistance to Ug99 from cultivar Gage, we characterized the genetics of stem rust resistance in Gage. We confirmed that a wheat stem rust resistance gene called Sr2 contributes to stem rust resistance in Gage. In addition, we postulated that two more genes contribute towards Gage resistance to stem rust. Understanding that multiple genes contribute towards stem rust resistance in Gage will facilitate breeding stem rust resistant wheat cultivars to protect United States wheat production from yield losses. Technical Abstract: Wheat (Triticum spp.) stem rust, caused by Puccinia graminis f. sp. tritici Eriks. & E. Henn. (Pgt), re-emerged as a devastating disease of wheat because of virulent race Ug99 (TTKSK). Many bread wheat (T. aestivum L.) cultivars grown in North America are susceptible to Ug99 or its derivative races with additional virulence. 'Gage' was released in 1963 mainly for its excellent field resistance to leaf rust (Puccinia triticina Eriks) and stem rust. However, Gage's resistance has not been genetically characterized, which would facilitate its use in breeding programs. To better define the nature of the resistance in Gage, we created an F2 population and the corresponding F2:3 and F4:5 families from crosses between Gage and stem rust susceptible cultivar 'Bill Brown'. Inheritance of seedling resistance to Pgt race QFCSC and molecular marker analysis indicated that Sr2 and additional genes explain the stem rust resistance of Gage. Using seedling plant infection types from the F2, F2:3 and F4:5 families, we confirmed that at least one dominant and most likely one recessive gene are involved in Gage's resistance. Seedling resistance genes acted independently of Sr2 since Sr2 is effective only at the adult plant stage. Adult plants without Sr2-linked marker gwm533 but with a resistant adult plant disease response indicated that at least one other gene is involved in adult plant resistance. |