Richard Wilson, an associate professor in the department of plant pathology at the University of Nebraska, will visit Illinois State to give a presentation on his research on the plant fungi pathogen, Magnaporthe oryzae.
His presentation, “Molecular mechanisms governing rice invasion by the blast fungus Magnaporthe oryzae,” will be given from 4-5 p.m. Thursday, April 9, in Moulton Hall, room 210.
Abstract of presentation
Increasingly, incidences of human disease, crop destruction and ecosystem perturbation are attributable to fungi and threaten socioeconomic progress and food security on a global scale. Rice contributes 23 percent of the calories consumed worldwide, but each year 10 to 30 percent of the global rice harvest—enough to feed 60 million people—is lost to infection by the rice blast fungus Magnaporthe oryzae. Containment of this severe threat to global food security might come from a better understanding of the molecular and cellular processes underlying the plant-fungal interaction.
M. oryzae is ideally suited to such study because: 1) it can be cultured away from its host plant, 2) it is amenable to rapid gene functional analysis, and 3) both M. oryzae and its rice host plant have sequenced genomes. M. oryzae plant infection is mediated by a specialized structure, called the appressorium, which develops from an asexual spore of M. oryzae adhered to the leaf surface. The mature appressorium generates enormous turgor through the accumulation of glycerol, and this pressure is translated into mechanical force acting on a penetration peg emerging at the base of the cell, causing it to breach the rice leaf cuticle and enter the plant. Once in the host, the penetration peg elaborates invasive hyphae that spread cell-to-cell, acquiring nutrients and colonizing living plant tissue for the first days of infection before causing disease. Remarkably, this early fungal growth stage occurs without activating the robust plant defenses that normally work to keep the host disease-free. However, despite the fundamental importance of this asymptomatic “biotrophic” growth stage to crop health, little is known about how—at the molecular level—fungal growth and plant defense suppression is coupled in the host cell.
Here, I discuss work from my lab that is aiming to enrich our understanding of how fungal cells thrive in living plant cells by focusing on the metabolic demands of biotrophy. This could lead to the development of novel crop protection strategies targeting molecular pathways that are critical for the biotrophic growth of the fungus but are not required for the normal function of the host cell.
