|4106 Throckmorton Plant Sciences Center|
Department of Plant Pathology
Kansas State University
The rice blast fungus Magnaporthe oryzae, (formerly Magnaporthe grisea), causes a serious disease of rice worldwide. The blast fungus leads a hemi-biotrophic lifestyle, which means that it initially invades living plant cells. However, cellular and molecular details of its biotrophic invasion strategy were not known. We are applying fungal molecular genetics, gene expression profiling, live-cell fluorescence microscopy and transmission electron microscopy to understand the early cellular and molecular interactions. Our goals are to understand how the fungus manipulates and colonizes live plant cells to cause disease, and how the plant sometimes blocks disease through resistance ( R ) gene mediated resistance. We aim to understand the dual roles for fungal avirulence (AVR) genes in establishing biotrophic infection (A) , or, in the presence of a corresponding R gene, in triggering hypersensitive resistance (B).
|(A) Successful infection occurs when the fungus invades living rice cells and forms extensive invasive hyphae within the cell. Around 36 hrs, invasive hyphae move synchronously into neighboring rice cells. (This image taken 36 hrs post inoculation)||(B) Resistance occurs when rice containing R gene Pi-ta recognizes the fungal AVR-Pita gene, triggering hypersensitive cell death and blocking further growth of the fungus.|
Light micrographs by Prasanna Kankanala