Rachel Mann

A new test will help protect Australia’s apple and pear  industry from a devastating bacterial disease affecting other countries, says a Victorian scientist.

Rachel Mann, of La Trobe University, has identified unique signatures in the DNA of fire blight-causing bacteria that can be targeted with a test, ensuring the accurate detection of the biosecurity hazard and the protection of the fruit industry’s economic viability.

“Maintaining Australia’s status as ‘fire blight free’ is not only important for protecting our industry from the disease, but also for retaining market access for Australian fruit into other countries,” says Rachel, who conducted the work at the Centre for AgriBioscience in a joint venture between La Trobe University and the Department of Environment and Primary Industries.

Fire blight is found in New Zealand, North America and Europe, but is not present in Australia.

“Fire blight causes the leaves, shoots and limbs of apple and pear trees to permanently shrivel and blacken. It can eventually kill whole trees and destroy orchards,” Rachel says.

By comparing the genomes of numerous fire blight-causing bacteria, Rachel identified unique signatures only found in the DNA of the fire blight bacteria, which could then be targeted for accurate diagnostic testing. Her work is set to have an international impact.

“Working with collaborators in the United States and Switzerland, we want our new tests to be accepted as the international standard for fire blight,” Rachel says.

“Additionally, as part of a new Plant Biosecurity CRC project, the methods used to develop improved tests for fire blight are now being used to improve tests for other microbes important to Australia’s biosecurity,” she says.

Victoria State Finalist: Rachel Mann, Department of Primary Industries Victoria /La Trobe University



Lucie Rankin

The discovery of a gene’s essential role in generating rare intestinal immune cells may hold hope for those with celiac disease or irritable bowel syndrome, say Melbourne scientists.

Lucille Rankin and a team at the Walter and Eliza Hall Institute discovered that the gene, T-bet, is important for the production of innate lymphoid cells, (ILCs) and is stimulated by the proteins from leafy greens, raising questions about the effect of food on our genes and immune system.

“Discovery of the T-bet molecule that make these immune cells paves the way for understanding how we might manipulate these cells and repair the communication breakdown that occurs in diseases such as IBS,” says Lucille, who did the research as part of her PhD.

ILCs help to promote good bacteria and the healing of small abrasions on the intestinal wall. Leafy green vegetables previously have been shown to have an important role in the production of ILCs. Lucille and her team discovered that the T-best molecule may be a possible pathway for this action.

The intestine makes up 70 per cent of our immune system and it is home to trillions of good bacteria that keep us healthy.  Immune cells in the intestine must be clever enough to tell the difference between good, health-promoting bacteria, harmless food particles and nasty disease-causing bacteria, which it must destroy.

When the communication system in the intestine breaks down, immune cells get confused and can begin to attack good bacteria and the intestinal lining, which results in irritable bowel syndrome (IBS) and colitis.  However, we still don’t know exactly how this happens and what causes such debilitating ailments.

Victoria State Finalist: Lucie Rankin, Walter and Eliza Hall Institute