Microscopic smallest, extremely disease-causing particles (lat. Virus = mucus, juice, poison), which are among the most dangerous enemies of the vine counting. Simple viruses usually consist of a protein shell and the nucleic acid enclosed in it (in contrast to the proteinless ones) viroids ). All viruses contain the program (some viruses also other auxiliary components) for their multiplication and spread. They do not consist of a cell and therefore do not have their own replication or metabolism and are therefore sensitive to the metabolism of a host cell, such as bacterium reliant.
According to the current wisdom, viruses are not to be counted as living beings, but they can at least be regarded as “close to life”. So far, 3,000 different species have been identified, but probably many more exist. They are only viable on the living tissue of a host and change its metabolism. The content of the host cell is completely dissolved and degenerated into a malignant cell.
Depending on the type of host cells, a distinction is made between plant and fungal viruses, which multiply almost exclusively in plant cells, bacterial viruses (bacteriophages), which rely on living bacterial cells, and animal viruses (animal viruses, which also include humans). All parts of the vine can be affected and lead to diverse degenerative changes. The symptoms or effects are weakness or short stature, leaf mosaic diseases, double knots, seedless Grapes and many other abnormalities. Viruses can also mutate and change as a result, and crossings are also possible.
Viruses are transmitted through, among other things nematodes (Roundworms) or insects such as the Rebenschmierlaus, The infected vines then spread to one vegetative propagation or at one finishing the viruses out. So far, around 40 types of virus have been specified that can affect the vine. Vine diseases caused by this are, for example Leaf roll disease. Legno Riccio. brushwood disease and various wood diseases (see under Rugose Wood Complex ). For all of them, this can lead to the complete destruction of vineyards, which must then be cleared.
The danger is so great because the viruses in root remains often live on for years. So you have to between the vineyard clear and leave new plants unused to deprive the nematodes of their livelihood. Viruses are also preventive through special ones pesticides (Virucides) fought. In general, virus-resistant is used for finishing today documents, The infection of a vine by certain viruses can be caused by the so-called Indexing be determined. Viruses are among other things with the thermotherapy fought. There are various methods for determining that vines are infected by viruses. These include, for example ELISA. Indexing and PCR, See also under Vine enemies,