From April 28, 2022, all seed for sowing imports into Australia, from all countries, will require a phytosanitary certificate. The only exclusion is for restricted seed species that require growth in post entry quarantine on arrival in Australia, or seeds imported for research purposes.
This is a requirement of seeds for sowing to protect against khapra beetle.
The specific information explaining the phytosanitary requirements can be found on the Departments website: Requirements for seeds for sowing to protect against khapra beetle.
This AQIS resource provides a “Permitted Seed for Sowing” listing. Very user friendly. Check your Genus-species before you order. If you have questions, they give straight forward answers to email queries within a day or two.
IMHO, all nation state agriculture governmental entities should use this as a template to prevent confusion and needless frustration for both importers and exporters. Really, its a no-brainer.