Abstract: During the months of January to April 2015, samples of diseased rice plants were collected in the Departments of Itapúa and Misiones for identification of parasitic diseases of rice. In the three departments were detected plants of variety IRGA 424, whose panicles showed grains affected with globose, powdery orange to grayish green masses. Symptoms and macroscopic observation of the reproductive structures of the pathogen in its natural substrate enabled the identification of the disease known as rice false smut caused by the fungus Ustilaginoidea virens (Cooke) Takahashi. This is the first report of rice false smut in Paraguay.
Fig.: Symptoms and signs of false smut caused by Ustilaginoidea virens (Cooke) Takah. in rice panicle: A, Spore galls on panicle; B, Chlamydospores.