Closteroviridae

Closteroviridae

The Closteroviridae is a family of viruses known for infecting plants. Members of this family are characterized by their long, filamentous virions and their ability to cause significant economic losses in agriculture due to the diseases they induce in crops. This family is part of the order Martellivirales.

Characteristics

Closteroviridae viruses are positive-sense single-stranded RNA viruses. They have a unique morphology, with virions that are typically 1250-2200 nm in length and about 12 nm in diameter. The genome of Closteroviridae is monopartite, meaning it consists of a single RNA molecule, which is quite large, ranging from 13 to 19 kilobases.

The family is divided into three genera:

• Closterovirus
• Ampelovirus
• Crinivirus

Each genus has distinct characteristics and host ranges, but all share the common feature of being transmitted by insect vectors, primarily aphids, whiteflies, and mealybugs.

Transmission

Closteroviridae viruses are primarily transmitted by insect vectors. The mode of transmission is semi-persistent, meaning the virus can be retained by the vector for a period of time but does not replicate within the vector. This mode of transmission is crucial for the spread of these viruses in agricultural settings.

Host Range and Symptoms

The host range of Closteroviridae is primarily limited to plants, with many members infecting economically important crops such as grapes, citrus, and vegetables. Symptoms of infection can vary widely depending on the virus and host but often include yellowing of leaves, stunted growth, and reduced yield.

Economic Impact

Viruses in the Closteroviridae family are responsible for several important plant diseases. For example, Citrus tristeza virus (CTV) is one of the most devastating diseases of citrus worldwide, leading to the decline and death of millions of citrus trees.

Also see

• Plant virus
• RNA virus
• Virus transmission
• Citrus tristeza virus