'Candidatus Phytoplasma australiense' is the phytoplasma associated with Australian grapevine yellows, papaya dieback and Phormium yellow leaf diseases.
Molecular studies carried out in New Zealand and Australia have shown that the phytoplasmas associated with Australian grapevine yellows, papaya dieback and Phormium yellow leaf diseases belong to the same species. This phytoplasma is distinct from German grapevine yellows (Vergilbungskrankheit) and stolbur. The name 'Candidatus Phytoplasma australiense' had previously been proposed for the phytoplasma associated with Australian grapevine yellows.
Phormium yellow leaf disease is a lethal disease of New Zealand flax (Phormium tenax) and mountain flax (P. cookianum), which is only present in New Zealand (first found in 1908). It is transmitted by a planthopper (Oliarus atkinsoni). Papaya dieback can be a devastating disease in Queensland, Australia (first found in 1922). Australian grapevine yellows was first reported in Australia in 1975. No vectors have been identified for the later two diseases. The authors noted that further studies are needed on the possible origin, host range, vector transmission of 'Candidatus Phytoplasma australiense' and the relationships between New Zealand and Australian populations.
Sources
Liefting, L.W.; Padovan, A.C.; Gibb, K.S.; Beever, R.E.; Andersen, M.T.; Newcomb, R.D.; Beck, D.L.; Forster, R.L.S. (1998) 'Candidatus Phytoplasma australiense' is the phytoplasma associated with Australian grapevine yellows, papaya dieback and Phormium yellow leaf diseases.
European Journal of Plant Pathology, 104(6), 619-623