|MAHONEY, AARON - Washington State University|
|BABIKER, EBRAHIEM - Washington State University|
|HULBERT, SCOT - Washington State University|
Submitted to: Molecular Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/3/2017
Publication Date: 10/3/2017
Citation: Mahoney, A.K., Babiker, E.M., See, D.R., Paulitz, T.C., Okubara, P.A., Hulbert, S.H. 2017. Analysis and mapping of Rhizoctonia root rot resistance traits from the synthetic wheat (Triticum aestivum L.) line SYN-172. Molecular Breeding. https://doi 10.1007/s11032-017-0730-9.
Interpretive Summary: Soiborne fungal pathogens of wheat continue to reduce the yield potential in Pacific Northwest production regions. This research describes resistance to one such pathogen in a CIMMYT synthetic wheat line. Resistance was manifest as reduced disease severity scores and little to no stunting in the presence of the pathogen in the field and growth chamber. Furthermore, molecular markers were identified for the resistance, which will enable breeders to transfer it to their spring wheats.
Technical Abstract: The prevalence of root disease after planting in cold spring soils has hindered the adoption of reduced or no-tillage cereal cropping systems in the Pacific Northwest. In particular, Rhizoctonia solani AG-8, a necrotrophic root pathogen, can cause significant damage to wheat stands under these conditions. In previous efforts to find root rot resistance, a CIMMYT synthetic wheat line, SYN-172 was found to have little to no seedling stunting from disease and lower root disease scores. To identify trait-maker associations, a population consisting of 150 BC1F5 recombinant inbred lines from a cross of ‘Louise’, a typically susceptible PNW cultivar, and SYN-172 was created. 689 polymorphic markers were used identify trait-marker associations for seedling stunting in a green bridge and growth chamber environments. In total five quantitative trait loci (QTL) were found on chromosomes 1AL, 2AL, 5BL, 7DS, and 7DL. One QTL on 2AL was consistently identified in all four of the environments tested. The QTL on 7DL was found consistently in all three of the field environments. The QTL on 2A and 7D have not been previously reported, and will be useful root rot resistance genes when transferred into the PNW spring wheat germplasm.