Phytoreovirus

background-color: rgb(250,250,190)" background-color: rgb(250,250,190)"

colspan=2 style="text-align: center; background-color: rgb(250,250,190)" | Phytoreovirus
colspan=2 style="min-width:15em; text-align: center; background-color: rgb(250,250,190)" | Virus classification

Phytoreovirus is a genus of viruses within the family Reoviridae. These viruses are known to infect plants, causing significant agricultural impact due to their ability to reduce crop yields and quality. Phytoreoviruses are transmitted by insect vectors, primarily leafhoppers, and are characterized by their double-stranded RNA genome.

Structure

Phytoreoviruses possess a non-enveloped, icosahedral capsid with a diameter of approximately 70 nm. The capsid is composed of multiple protein layers, providing protection to the viral genome. The genome itself is segmented, consisting of 10-12 segments of double-stranded RNA, which encode for various structural and non-structural proteins.

Genome and Replication

The genome of phytoreoviruses is segmented, with each segment encoding one or more proteins. The replication cycle of phytoreoviruses occurs in the cytoplasm of the host cell. Upon entry into the host cell, the virus uncoats and releases its RNA segments, which are then transcribed by the viral RNA-dependent RNA polymerase. The resulting mRNA is translated into viral proteins, which assemble into new virions.

Transmission

Phytoreoviruses are primarily transmitted by insect vectors, particularly leafhoppers. The virus is acquired by the insect during feeding on an infected plant and is then transmitted to other plants as the insect continues to feed. This mode of transmission is known as persistent-propagative, meaning the virus can replicate within the insect vector and be transmitted over the insect's lifetime.

Symptoms and Impact

Infected plants often exhibit symptoms such as stunted growth, leaf curling, and chlorosis. These symptoms can lead to reduced photosynthetic capacity and overall plant vigor, resulting in decreased crop yields. The economic impact of phytoreovirus infections can be significant, particularly in regions where susceptible crops are grown extensively.

Management and Control

Management of phytoreovirus infections involves integrated pest management strategies to control the insect vectors. This includes the use of insecticides, resistant plant varieties, and cultural practices such as crop rotation and removal of infected plants. Research into the molecular biology of phytoreoviruses is ongoing, with the aim of developing more effective control measures.

Also see

• Reoviridae
• Plant virus
• Leafhopper
• RNA virus