LAUSR

Zucchiniand Tobacco Yellow Mosaic (ZYMV and TMV, respectively) are the most destructive and widespread virus diseases on Cucurbits and Tobacco worldwide. Even though they belong to different genera (Potyvirus and Tobamovirus, respectively) they induce similar symptoms on the plants such as stunting, yellowing and deformation of the leaves. In advanced stages of the infection, leaves develop yellow mosaic and often show dark green blisters [1,2]. Transmission electron microscopy (TEM) has been intensively applied to detect and identify ZYMV and TMV in the sap of plants, to characterize ultrastructural changes, and to rapidly diagnose these diseases in less than half a day [3,4]. These studies revealed that ZYMV induces the formation of cylindrical inclusions (CI) in the cytosol, while TMV simply accumulates in the cytosol in parallel form [3]. All of these studies focused on the 2 dimensional characterization of ZYMV and TMV diseases and therefore very little is known about how these changes affect the 3 dimensional ultrastructure of plant cells. In this study serial sections (section thickness was 80 nm) of ZYMV and TMV infected leaves were 3D reconstructed by computer supported TEM in order to investigate 3D ultrastructural changes induced by ZYMV and TMV in leaves of Cucurbita pepo L. and Nicotiana tabacum L., respectively.