Programmed Cell Death Mediated by Non-Host Resistance in Arabidopsis Against Rice Blast

Abstract

Rice blast is one of the major diseases in rice deterring the crop production up to 30% which in turn affects global food security. The devastating disease is caused by filamentous hemibiotrophic ascomycetes, Magnaporthe oryzae. Several studies on the identification of the disease resistance genes hitherto resistant cultivar did not solve to culminate the disease from the field. However, there are plants in nature that are not infected by the rice blast pathogen and are known to be non-host. A non-host plant provides broad-spectrum disease resistance against a pathogen race. The infected cells communicate and activate the cell death in an orchestrated fashion. The NHR mechanism results in hypersensitive responses like oxidative burst and programmed cell death (PCD) at the site of infection that restricts further spreading of the disease into adjacent cells. Although disease resistance played by various NHR genes is reported, the underlying molecular mechanism of NHR and PCD remains elusive. Thus, the present study focuses on the comparative oxidative burst, ion leakage, and cell death corresponding to disease resistance in different mutants of Arabidopsis. This study can lead to the identification of the active protagonists from the non-host and help in engineering broad spectrum and durable disease resistant rice. Further, the cell death pathway will be studied to delineate its relevance if any in the host.