This aspect is particularly relevant for pathogens like Xf that invade a plant’s vascular (circulatory) system because the bacteria eventually block the water flow, causing similar symptoms that can be wrongly attributed to lack of water. Hyperspectral image data gathered on flights are analysed for traits linked to plant health at resolutions that allow assessment for each tree. But a common problem is that the remote sensing algorithms that scan the hyperspectral images can’t always distinguish the symptoms of Xf from the symptoms of other pathogens or environmental stress like lack of water or nutrients. Hyperspectral images allow us to “see” in more fine-grained wavelengths, and our previous research has already demonstrated that we can use it to detect Xf in olive trees before symptoms were visible. And during this period, the asymptomatic plants continue to be infectious.īut our new research takes us a step closer to developing a rapid and more accurate large-scale screening process of at-risk crop species by enhancing the effectiveness of airborne scanning that uses hyperspectral imaging. The key to containing Xf is early detection, which isn’t easy given that some infections don’t cause visual symptoms until 8-10 months. Protecting Australia's citrus industryĪlready widely distributed in the Americas, it has been identified in Spain, France, Israel, Iran and Taiwan, raising international alarms about the potential for a global Xf epidemic. If it spreads through Europe the losses in just the olive industry alone are projected to reach up to €5.2 billion per year. In Apulia, Italy, Xf has left devastating scenes of dead and dying olive trees in its wake and it could cost $US22 billion to control the outbreak there over the next 50 years. Overseas, Xf is arguably the greatest disease threat to food security and agricultural productivity worldwide. In parts of Europe, Xf has devastated crops like olive. It could also infect native Australian and ornamental plants. This so far incurable bacterial disease causes plants to wither and possibly die (dieback), scorching and browning leaves and reducing the size of fruit in a wide variety of important crops including olive, almond, avocado, coffee, grapevine, citrus and many herbaceous and forest species. But the way things are going, we will be hearing a lot more about Xf. The number one biological security threat to Australian agriculture is a bacteria most will never have heard of – Xylella fastidiosa ( Xf).