Location: Cereal Disease LabTitle: Inheritance and bulked segregant analysis of leaf rust and stem rust resistance genes in eight durum wheat genotypes
|AOUN, MERIEM - North Dakota State University|
|Kolmer, James - Jim|
|BULBULA, WORKU - Ethiopian Institute Of Agricultural Research|
|ELIAS, ELIAS - North Dakota State University|
|Rouse, Matthew - Matt|
|ACEVEDO, MARICELIS - North Dakota State University|
Submitted to: Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/17/2017
Publication Date: 12/1/2017
Citation: Aoun, M., Kolmer, J.A., Chao, S., Bulbula, W.D., Elias, E., Rouse, M.N., Acevedo, M. 2017. Inheritance and bulked segregant analysis of leaf rust and stem rust resistance genes in eight durum wheat genotypes. Phytopathology. 107:1496-1506.
Interpretive Summary: Leaf rust is a disease of wheat caused by the fungus Puccinia triticina. Durum wheat is particular susceptible to certain types of the leaf rust fungus. The objective of this research were to find new genes for leaf rust resistance in durum wheat. Possible new genes for leaf rust resistance were found on four different chromosomes in durum wheat. A gene for stem rust resistance in durum wheat was located to a different chromosome. This information can be used to develop durum wheat cultivars with better rust resistance.
Technical Abstract: Leaf rust, caused by Puccinia triticina (Pt) and stem rust caused by Puccinia graminis f. sp. tritici (Pgt) are important diseases of durum wheat. This study determined the inheritance and genomic locations of leaf rust resistance (Lr) genes to Pt-race BBBQJ and stem rust resistance (Sr) genes to Pgt-race TTKSK in durum accessions. Eight leaf rust resistant genotypes were used to develop bi-parental populations. Accessions, PI 192051 and PI 534304 were also resistant to Pgt-race TTKSK. The resulting progenies were phenotyped for leaf rust and stem rust response at the seedling stage. The Lr and Sr genes were mapped in six populations using SNP markers and bulked segregant analysis. Five leaf rust resistant genotypes carry single dominant genes on chromosomes 2B, 4A, 6BS, and 6BL. In the remaining accessions, the segregation did not fit into the expected segregation ratio of a single dominant gene. Further mapping using KASP assays, showed that the single dominant Lr gene in PI 209274 was flanked by IWA3298 and IWB39456 on 6BS. Seven genotypes carry different Lr genes to those previously characterized in durum wheat cultivars. The Sr gene in PI 534304 is most likely Sr13.