Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 7, 2004
Publication Date: October 1, 2004
Citation: Kolmer, J.A., Long, D.L., Hughes, M.E. 2004. Physiologic specialization of Puccinia triticina on wheat in the United States in 2002. Plant Disease. 88:1079-1084 Interpretive Summary: Collections of the rust fungus Puccinia triticina, that is the cause of the leaf rust disease on wheat, were obtained from the major wheat growing regions of the U.S. in 2002. The collections of the leaf rust fungus were purified on seedlings of wheat plants in greenhouses, and were then tested for their ability to attack 16 different types of wheat, that each have a different gene that gives resistance to the leaf rust fungus. From the many collections (785) that were tested on the wheat lines, 52 different types of leaf rust (physiologic races) were described in the U.S. in 2001. Different races of leaf rust were found in the southeastern states and the Ohio Valley areas where soft red winter wheats are grown, compared with races that were found in the southern and northern Great Plains region of the U.S where hard red winter and spring wheats, respectively are grown. The leaf rust races differ in their ability to attack the different types of wheat cultivars that are grown in the U.S., which has lead to the different wheat growing areas of the U.S. having different leaf rust races. The results from this study can be used by wheat breeders and plant pathologists to determine which leaf rust resistance genes can be added to wheat breeding programs in order to develop wheat cultivars with good resistance to the many different races of the leaf rust fungus.