A method of producing a picornavirus-like particle (PVLP) in a plant is provided. The method comprises introducing a first nucleic acid and a second nucleic acid into the plant, portion of the plant, or a plant cell. The first nucleic acid comprising a first regulaton region active in the plant operatively linked to a nucleotide sequence encoding a picornavims polypeptide. The second nucleic acid comprising a second regulaton region active in the plant and operationally linked to a nucleotide sequence encoding one or more picornavims protease. The plant, portion of the plant, or plant cell is incubated under conditions that permit the expression of the nucleic acids, thereby producing the PVLP. A PVLP comprising the polypeptide is also provided.
