Vitis labrusca leaf infected with Xylella fastidiosa. Left image is a scanning electron microscope image superimposed with a silicon (Si)-rich area map (green/yellow/red), and the right image is a 3D Si-rich signal intensity map. Leaf scorch lesion surrounded by healthy tissue (blue/white). 3-D map is slighted tilted.
Breno LeiteThermo Fisher Scientific-X-Ray MicroanalysisEmail: email@example.com
Pierce’s disease (PD) is caused by the pathogenic bacterium Xylella fastidiosa and has resulted in serious losses for the multi- million dollar grape and wine industry in California. Similar problems are also a concern for the state of Florida. The disease remains incurable. European grapes (Vitis vinifera) are the most susceptible to PD. American varieties such as Vitis labrusca grapevines are also susceptible, contrasting with Muscadine grapes (Vitis rotundifolia), which are highly tolerant to the disease. Mechanisms of host resistance are not fully understood. The image above shows a typical V. labrusca scorched lesion area that was mapped using modernized high-throughput energy dispersive spectroscopy (EDS) coupled with scanning electron microscopy. Images show a typical leaf scorch area accumulating silicon (Si). The lesion is surrounded by healthy tissue exhibiting normal levels of Si. Si accumulation is probably a plant strategy to cope with the reduction in water flow as a consequence of vessel occlusion due to bacterial multiplication (Leite, B., and Andersen, P. C. 2009. Microsc. Microanal. 15 (2):918-19). These findings encourage discussions concerning the importance of Si as an element involved in stress-related responses and emphasizes the impact of the new generation of EDS detectors. These detectors are able to produce massive amounts of X- rays and help to reveal fine details of the plant response to a pathogen.
APS publication number: IW000116
Picture your photograph as the APSnet Featured ImageClick here to find out more
License to Copy. This notice hereby grants permission to APSnet users to copy the image featured for noncommercial, personal use. All components of APSnet are copyrighted and may not be reproduced or distributed except by express permission of APS. Copyright is not claimed for material provided by United States government employees as part of their work. APSnet copyright extends to images, text, graphics, photographs, illustrations, audio, video, computer software, and all other elements of the site.Instructions to Copy. For PC, position your mouse cursor on the featured image, click the right mouse button, and choose "Save Picture As..." or "Save this Image as..." whichever is the case. For Mac, click the only mouse button and follow the same steps. Users may want to set up a specific directory and file naming scheme for storing images; otherwise, they will be saved using your system defaults. Images may be used in any software application that supports JPEG file format or viewed in an Internet browser as local files.