The University of British Columbia

Purpose

Pea root rot complex is a serious threat to pea and lentil production in the Canadian prairies because there is limited genetic resistance in pea and there is no effective fungicide treatment. As a result, novel methods of root rot disease control are in urgent demand by pea farmers. The plant root microbiome includes microbes that can kill fungal and oomycete pathogens, including those present in the pea root rot complex. In this project, the aim is to identify the host and microbial genetic factors that recruit beneficial microbes to promote resistance of pea to root rot diseases. The Haney Lab at UBC studies genetics and genomics of beneficial Pseudomonas fluorescens interactions with plants; these bacteria will be used as an example of beneficial rhizosphere microbes in this project. The Haney lab also has a collection of hundreds of genome-sequenced P. fluorescens isolates including many with characterized antifungal activity. First, genome-sequenced isolates of P. fluorescens will be used in a highthroughput phenotyping approach coupled with a well-established comparative genomics, transcriptomics and metabolomics pipeline. This will identify bacterial strains, genes and mechanisms that allow Pseudomonas strains to kill root rot pathogens. To identify plant genes that recruit beneficial P. fluorescens, we will screen pea genotypes from an association mapping (AM) panel available from our NRC collaborator. This information will be used in a genome wide association study (GWAS) or traditional mapping to identify pea genetic factors that can recruit beneficial P. fluorescens.The Project goal is to deliver bacterial strains or genetic loci that can control root rot pathogens of pea, and pea cultivars, genes or genetic markers that are associated with disease-suppressive microbiomes. This work will provide an avenue to breed pea varieties that sustain high levels of beneficial microbes, and for application of beneficial microbes to control root rot disease in the field.