IDENTIFICATION AND CHARACTERIZATION OF CANDIDATE SECRETED EFFECTOR PROTEINS IN THE RUST PATHOGEN PUCCINIA SORGHI

The goals of this predoctoral fellowship research project are to identify and characterize the role in modulating plant immunity of a specific family of cysteine-rich candidate secreted effector proteins (CSEPs), known as cluster 112, of the maize common rust pathogen Puccinia sorghi. This will develop P. sorghi as a model for rust-plant interactions that can be applied to other rusts.To accomplish these goals, three objectives are proposed:Develop a highly contiguous and complete P. sorghi genome sequence by long-read sequencing. The genome will be phased to separate the two genetically distinct nuclei of the urediniospores that infect maize. This will provide an extremely accurate and complete look at the genome of this rust species.Characterize cluster 112 CSEPs to identify functions in suppressing host immunity and host target proteins. Understanding the roles various rust effectors play and their specific host targets can spur breeding efforts to reduce the harm of plant-pathogenic rusts.Silence expression of host proteins that interact with cluster 112 CSEPs using virus-induced gene silencing and phenotype the resulting rust disease development with image-based computer vision techniques. This pipeline will provide a means to identify host proteins that have the largest effect on disease severity. The development of a computer-vision based phenotyping method will allow for extremely accurate phenotyping.