Location: National Programs
Project Number: 0500-00053-004-013-G
Project Type: Grant
Start Date: Apr 24, 2016
End Date: Apr 23, 2021
Objective:
Project 1: Better define the mechanism of a resistance response that we have
observed that is specific to trichomes and silica cells in two row barley, but only very infrequently in six-row barley, and appears to halt ingress of F. graminearum into the palea.
Project 2: Investigate the role that silicon (Si) and its derivatives play in host interactions with Fusarium graminearum.
Project 3: Investigate the role of MAT1-1-1 and MAT1-2-1 proteins on the regulation of genes that negatively impact aggressiveness and toxigenicity of the heterothallic strains of F. graminearum.
Approach:
Project 1: 1) Determine whether the resistance response we have documented in barley trichomes/silica cells is correlated with cessation of fungal penetration; 2) Characterize the resistance response in two- and six-row barley lines to determine if the response differs between these classes of barley. Use progeny of a two- and six-row barley cross to determine segregation pattern of resistance and barley type; 3) Determine if known barley powdery mildew pathogenesis-related genes MLO and ROR2 alter the observed resistance response associated with barley trichomes/silica cells.
Project 2: (1) Test ability of F. graminearum wild-type and MIP mutants to grow on silica in culture and its effect on differentiation. (2) Test the influence of Si levels in barley florets on the pathogenicity and perithecium development of F. graminearum. (3) Perform transcriptomics under high and low Si conditions both in culture and on barley florets. (4) Knockout genes identified in (3) as having the largest change in expression associated with presence of Si to determine how the fungus senses Si and how Si affects pathogenicity.
Project 3: (1) Perform a comparatie Illumina RNA-seq analysis of the wild tye (WT) and KO transcriptomes in wheat heads, to reveal genes that are altered by activity of the hterdimeric mating specificy versus by the non-dimerized forms. (2) Perform acytological analysis of the KO tranformants expressing fluorescent proteins in inoculated wheat heads, tp characterize the reduced aggressiveness of the MAT1-1-1 and MAT10201 specificity gene KOs in detail. (3) Produce complentation strains for each of the specificity gene KOs, and use quantiative realtime PCR to evaluate the expression of the MAT1-1-1 and MAT1-2-1 genes, and of pathogenicity genes reported in the literature, in the W&, KO and complented strains.
