Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/14/2016
Publication Date: 11/2/2016
Citation: Peters, A.R., Friesen, T.L., Faris, J.D. 2016. Quantification of disease expression conferred by three host gene-necrotrophic effector interactions in the wheat-Parastagonospora nodorum pathosystem [abstract]. Durable Wheat Resistance Meeting, November 2-3, 2016, Minneapolis, MN.
Technical Abstract: The disease Septoria nodorum blotch (SNB) is caused by the necrotrophic fungal pathogen Parastagonospora nodorum, which induces cell death in wheat through the production of necrotrophic effectors (NEs). The objective of this project is to determine the relative importance of three host gene-NE interactions in causing disease. A recombinant inbred population that segregates for the NE sensitivity genes Tsn1, Snn1, and Snn3-B1, which interact with the NEs SnToxA, SnTox1, and SnTox3, respectively, was developed for genetic analysis. Results from infiltrations using Pichia pastoris cultures expressing each NE individually were used to map the three genes onto a whole-genome linkage map, which was assembled using SSR markers and the wheat 9K iSelect SNP array. Phenotypic data was collected by conducting spore inoculations using various isolates that produced one or more of the three NEs, and subsequent QTL analysis was conducted to determine the effects of the compatible host gene-NE interactions in causing disease. The amount of disease variation explained by the different interactions varied among isolates, and in some cases the evaluation of NE gene-knockout isolates compared to corresponding wild types indicated strong epistasis for some host gene-NE interactions. Experiments to determine if NE expression is associated with disease significance are currently being conducted. Results from this research will contribute to the understanding this pathosystem and provide researchers with knowledge for reducing losses to SNB.