Drought, salinity, flooding and extreme temperatures threaten many plants essential to humankind - and scientists at The University of Western Australia have discovered how they respond to these challenges.
Lead researcher Winthrop Professor Steven Smith, of the Australian Research Council Centre of Excellence in Plant Energy Biology based at UWA, said understanding how plants grow under stressful environmental conditions was vital for food, fuel and fibre production.
His team's discovery of a new molecular mechanism by which plants deal with stress is published today as the cover-page article by the American Association for the Advancement of Science in their marquee journal, Science Signaling.
"We found that when plants are stressed they respond by increasing their sensitivity to a steroid growth hormone called brassinosteroid. This provides a way for them to step up to the challenge of growth in harsh conditions," Professor Smith said.
"Our discovery - a great piece of scientific detective work - shows that a plant does not just succumb to whatever the weather serves up: it responds positively by putting energy into continued growth even under difficult circumstances. This finding opens a new door to find ways to identify or select plants that perform better in difficult conditions."
Lead author Ping Che, Research Assistant Professor in UWA's Centre of Excellence for Plant Metabolomics said: "We linked two previously unconnected research fields. It was known that environmental stresses trigger a ‘quality control' system in the internal membranes of plant cells but the targets of this QC system were unknown.
"We also had circumstantial evidence that brassinosteroids were involved in stress responses in plants. We discovered that the QC system directly activates brassinosteroid sensing which in turn provides stress tolerance. Mutants defective in the QC system were sensitive to stress but this could be overcome by directly activating the steroid response system."
The research was carried out in collaboration with scientists at the Australian National University's node of Plant Energy Biology. Research Assistant Professor Che is now a visiting researcher in one of the world's top brassinosteroid research laboratories at the SALK Institute in San Diego, where he is taking the next step forward in this research.
Winthrop Professor Steven M Smith (ARC Centre of Excellence in Plant (+ 61 8) 6488 4403 Energy Biology and School of Biomedical Biomolecular and Chemical Sciences)
Janine MacDonald (UWA Public Affairs) (+61 8) 6488 5563 / (+61 4) 32 637 716