2. Symptomatology and Economic Impact Phytoplasmas are associated with diseases in several hundreds of plant species, including many economically important food, vegetable, and fruit crops; ornamental plants, timber and shade trees. Typical symptoms include virescence/phyllody (development of green leaf like structures instead of flowers) (Figure 2), sterility of flowers, proliferation of axillary buds resulting in a witches’ broom growth, abnormal internodes elongation and generalized stunting. Phytoplasmas may induce many other nonspecific symptoms resulting from stress to which the infected plants are subjected. Hovewer not all infections are necessarily deleterious. For example, the free branching form of poinsettia has been widely used in commercial production of this popular seasonal ornamental, as this trait results in smaller potted plants with numerous show