Pathway not proven. Only one dated (1955) reference found indicating seed may be a pathway on P. obconica. This reference could not be verified. Considered an occasional pest of most Primula cultivars in use today.
Chase, AR, Daughter, ML and Cloyd, RA. 2018. Compendium of Bedding Plant Diseases and Pests. American Phytopathological Society. St. Paul MN USA. https://apsjournals.apsnet.org/doi/10.1094/9780890546024.fm#