Background/context:

Candidatus Phytoplasma australiense is the most economically important pathogenic phytosplasmas to Australia. Phytoplasmas are associated with papaya dieback, strawberry lethal yellows, Australian lucerne yellows and stylosanthes little-leaf, to name a few. The centre’s work on phytoplasmas in stylosanthes and sugarcane highlighted the need for tests to a) resolve closely related strains and b) permit high throughput screening for epidemiology studies.

 Aim:

The object of this sub-project was to increase understanding of the phytoplasma genome to identify new ways to resolve strains and to detect phytoplasmas efficiently and economically. To do this the sub-project aimed to obtain a more extensive phytoplasma genomic library, identify and characterise key tomato big bud (TBB) phytoplasma genes, express key genes and produce antisera to develop novel diagnostic probes and develop novel serology tests using antisera from expressed proteins.

Major Outcomes:

For the first time in Australia, a phytoplasma genome has been sequenced and annotated – the Candidatus Phytoplasma australiense. From this work, the discovery of a phytoplasma gene has formed the basis of a reliable, sensitive, specific and high-throughput single tube diagnostic test. A phytoplasma diagnostics manual has been prepared that covers both the conventional polymerase chain reaction (PCR) test and the new real-time PCR test. CRCTPP was involved in setting up a molecular facility called Bioscience North Australia (BNA) to ensure the long-term viability of this molecular and diagnostic work, which is strongly supported by Charles Darwin University and the Northern Territory government.

For more information contact:

Dr Karen Gibb
Charles Darwin University
Phone: +61 (0)8 8946 6705
Email: kgibb@darwin.cdu.edu.au