Plant parasitic microorganisms (formerly Mycoplasma-like organisms), which were renamed phytoplasmas (phyto = plant) in 1994 to differentiate them from animal parasitic mycoplasmas. They are the bacteria similar, but in contrast to these have no cell walls, but are surrounded only by a flexible cell membrane. Therefore, their shape is irregular and may be oval, oblong or multifarious. In contrast to virus are they capable of self-sufficient reproduction? They are so tiny that they can no longer be perceived in the light microspop. This organism group was first established in 1967 in connection with the causes research of yellowing diseases Xylem (Phloem) discovered by plants.
Phytoplasmas colonize the sieve tubes and the cells adjacent to the phloem. In the host plants, they cause abnormal and terminally fatal changes. These are yellowing, shoot shortening, leaf deformation and broom growth, In some plant species they enlarge the flowers, these take on the shape of leaves. Phytoplasmas are caused by insects such as cicadas transfer. This will cause different vine diseases like Flavescence dorée (Golden yellowing yellowing), Blackwood's disease (by the type Stolbur), grapes wilt and yellowing (Grapevine yellows) caused. Phytoplasmas are classified as quarantine organisms due to their hazardous nature in the EU. They are quite successfully fought with hot water. See also a complete list of all diseases and pests below Vine enemies,
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