Potexvirus

Potexvirus is a genus of positive-sense single-stranded RNA viruses in the family Alphaflexiviridae. The name "Potexvirus" is derived from Potato virus X, the type species of the genus. These viruses are known to infect a wide range of plant species, causing various mosaic and other leaf symptoms, and can lead to significant economic losses in agriculture.

Potexviruses are filamentous and flexuous, with particle lengths typically ranging from 470 to 580 nanometers and a diameter of about 13 nanometers. Their genome consists of a single molecule of RNA, which is approximately 6.4 to 7.4 kilobases in length. The genome encodes at least four open reading frames. The structural protein of the virion, the coat protein, is the most abundant protein and is essential for virion assembly and stability. Other proteins include a replication-associated protein, a movement protein that facilitates cell-to-cell spread within the plant, and a putative silencing suppressor.

Transmission of potexviruses primarily occurs mechanically through contact with infected plant material, such as during agricultural practices like pruning or harvesting, or through sap transfer. Some potexviruses can also be transmitted by vegetative propagation. Natural vectors like insects are generally not involved in their spread. There is no known cure for potexvirus infections in plants. Management strategies focus on prevention, including using certified virus-free planting material, maintaining good sanitation practices, and controlling weed hosts that may harbor the virus. Resistance in some plant cultivars can also play a role in limiting disease spread.