Dichorhavirus

Dichorhavirus

Dichorhavirus is a genus of plant viruses in the family Rhabdoviridae. These viruses are known to infect a variety of plant species, causing significant agricultural impact. The name "Dichorhavirus" is derived from the Greek words "di" meaning two, "choros" meaning place, and "virus", reflecting the bipartite nature of their genome and their systemic infection in host plants.

Taxonomy

Dichorhavirus is classified under the order Mononegavirales, family Rhabdoviridae. The genus includes several species, each with distinct host ranges and geographical distributions. The type species of this genus is Orchid fleck virus (OFV).

Genome and Structure

Dichorhaviruses have a bipartite, negative-sense, single-stranded RNA genome. The two segments of the genome are encapsidated in separate, bullet-shaped virions. Each segment encodes different proteins essential for the virus's replication and movement within the host plant.

Segment 1

Segment 1 encodes the nucleocapsid protein (N), phosphoprotein (P), and the large polymerase protein (L). These proteins are crucial for the replication of the viral RNA.

Segment 2

Segment 2 encodes the glycoprotein (G) and the matrix protein (M), which are involved in the assembly and budding of new virions.

Transmission

Dichorhaviruses are primarily transmitted by eriophyid mites, which act as vectors. The mites acquire the virus by feeding on infected plants and subsequently transmit it to healthy plants. This mode of transmission is highly efficient, facilitating the spread of the virus across large areas.

Symptoms and Host Range

Infected plants often exhibit symptoms such as chlorotic flecks, mosaic patterns, and necrotic lesions on leaves. The severity of symptoms can vary depending on the host species and environmental conditions. Dichorhaviruses have a broad host range, including economically important crops such as orchids, citrus, and coffee.

Diagnosis and Management

Diagnosis of dichorhavirus infections is typically performed using molecular techniques such as RT-PCR, which can detect the presence of viral RNA in plant tissues. Management strategies include the use of virus-free planting material, control of mite vectors, and the implementation of quarantine measures to prevent the introduction of the virus into new areas.

Research and Developments

Recent research has focused on understanding the molecular biology of dichorhaviruses, their interaction with host plants, and the development of resistant plant varieties. Advances in genomic technologies have facilitated the sequencing of dichorhavirus genomes, providing insights into their evolution and adaptation.

Also see

• Rhabdoviridae
• Mononegavirales
• Plant virus
• Orchid fleck virus
• Virus transmission