Concurrent Session
Rebecca Degnan
The University of Queensland
Brisbane, Queensland, Australia
Leny Jane Pame
The University of Queensland
Brisbane, Queensland, Australia
Sebastian Orellana-Quinteros
The University of Queensland
Brisbane, Queensland, Australia
Ken Pegg
Queensland Department of Primary Industries
Brisbane, Queensland, Australia
Donald Gardiner
QAAFI, University of Queensland
St Lucia, Queensland, Australia
Alistair McTaggart
The University of Queensland
Brisbane, Queensland, Australia
Louise Shuey
Queensland Department of Primary Industries
Brisbane, Queensland, Australia
Bernard Carroll
The University of Queensland
Brisbane, Queensland, Australia
Neena Mitter
Charles Sturt University
Wagga Wagga, New South Wales, Australia
Anne Sawyer
QAAFI/SCMB University of Queensland
St Lucia, Queensland, Australia
Plant pathogens threaten global food security and biodiversity, causing yield losses in crops and epidemics in natural ecosystems leading to population decline and extinctions. Disease management relies heavily on chemical pesticides, but these are harmful to humans and the environment and lead to pathogen resistance. RNA biopesticides have emerged as a game-changing non-GM pathogen-specific crop protection platform that does not leave harmful residues in the environment or impact beneficial organisms. The approach involves spray application of pathogen-specific double-stranded RNA (dsRNA) to plants to trigger RNA interference (RNAi) in the invading pathogen. Essential pathogen genes are silenced, inactivating the pathogen and preventing infection. We are developing RNA biopesticides against foliar and soilborne pathogens including Austropuccinia psidii (myrtle rust) and Phytophthora cinnamomi (Phytophthora root rot). We have demonstrated that exogenous dsRNA targeting conserved fungal genes is highly effective as both a preventative and curative treatment against myrtle rust. The approach also shows promise against P. cinnamomi, with co-treatment of lupins with dsRNA and a low dose of potassium phosphonate protecting against root rot. Interestingly, changes in host rather than pathogen gene expression appear to drive the protective response. Our findings demonstrate the potential of dsRNA for management of plant diseases and will guide a future of innovative crop protection.