Figure 12.  Pinto bean leaves with necrotic local lesions caused by Tobacco mosaic virus (left) [far view]. The dark brown spots on the leaves correspond to the locations where the virus entered the leaf and caused the surrounding tissue to die (right) [close up]. The white irregularly-shaped areas on the leaf are typical of leaf damage caused by rubbing too hard during inoculation (Photos courtesy R. Ford, From: Ford and Evans 2003).