Magnaporthe grisea, also known as Rice Blast fungus, Rice Rotten neck, Rice Seedling blight, Blast of rice, oval leaf spot of Graminea, pitting disease, ryegrass blast, and johnson spot, is a plant-pathogenic fungus that causes an important disease affecting rice. It can also infect a number of other agriculturally important cereals including wheat, rye, barley, and pearl millet causing diseases called blast disease or blight disease. M. grisea causes economically significant crop losses annually, each year it is estimated to destroy enough rice to feed more than 60 million people. The fungus is known to occur in 85 countries worldwide. It is sometimes thought of as a model organism in the study of phytopathogenic fungi.