Does soybean use a fungal polyamine oxidase to induce immunity?
J. BAUMBACH (1), M. Bhattacharyya (1) (1) Iowa State University, U.S.A.

Soybean is an important source of protein and oil for both human and livestock consumption. Soybeans suffer yield losses from a variety of pathogen species. One such species is the destructive fungal pathogen Fusarium virguliforme that causes sudden death syndrome (SDS). SDS is an emerging disease, which is spreading throughout the soybean growing regions of both North and South America. The pathogen expresses two polyamine oxidase genes. FvPO1, encoding one of the enzymes is rapidly induced following infection. To better understand the possible role of FvPO1 in SDS development, knockout and complemented mutants were created. Contrary to our hypothesis that FvPO1 could be involved in SDS development, fvpo1 mutants were able to produce enhanced SDS symptoms as compared to the wild type Mont-1 and complemented mutant strains. A comparative transcriptomic study reveals that expression of 57 soybean genes including six transcription factors, five oxidation-reduction genes, and seven stress responsive genes is increased in response to fvpo1 infection as compared to that by Mont-1. The increased expression levels of stress-related genes suggest increased amounts of F. virguliforme-infected tissues supporting our phenotypic analysis of fvpo1. Our observations suggest that soybean uses FvPO1 to release free radicals to fight the SDS pathogen.

Abstract Number: P17-493
Session Type: Poster