Identification and Characterization of Novel Candidate Effector Proteins from .

The fungal pathogen secretes a large number of effector proteins to facilitate infection, most of which are not functionally characterized. We selected potential candidate effector genes from the genome of , field isolate P131, and cloned 69 putative effector genes for functional screening. Utilizing a rice protoplast transient expression system, we identified that four candidate effector genes, , , and induced cell death in rice. In particular, also induced cell death in leaves through Agrobacteria-mediated transient gene expression. We further identified that six candidate effector genes, to , suppress flg22-induced ROS burst in leaves upon transient expression. These effector genes were highly expressed at a different stage after infection. We successfully knocked out five genes in , , , , and . The virulence tests suggested that the deletion mutants of , and showed reduced virulence on rice and barley plants. Therefore, those genes play an important role in pathogenicity.