First report of blast disease on Oplismenopsis najada caused by Pyricularia oryzae in Argentina

Abstract In 2022, Pyricularia blast‐like symptoms were observed in Oplismenopsis najada plants in Argentina. P. oryzae was identified based on its cultural and morphometric characteristics, nucleotide sequencing of ITS1‐5.8S‐ITS2 amplicons, complemented with phylogenetic analyses, and PCR with Pot2 marker. Koch's postulates were confirmed on O. najada and the Guri INTA CL variety of Oryza sativa . The obtained sequences were deposited in GenBank (ITS: OR741772 ). The PCR reaction amplified the Pot2 marker, confirming that it is P. oryzae . To our best knowledge, this is the first report of O. najada as new host of P. oryzae worldwide.