betaflexiviruses

Betaflexiviruses are a genus of plant-pathogenic viruses in the order Martellivirales and the family Alphaflexiviridae. They are characterized by their flexuous, filamentous virions, which are typically around 650-800 nm in length and 12-13 nm in diameter. The genome of betaflexiviruses consists of a single-stranded, positive-sense RNA molecule. This RNA genome encodes several proteins, including a replicase, movement protein, coat protein, and a suppressor of RNA silencing.

The replication cycle of betaflexiviruses involves the synthesis of a genomic RNA and subgenomic RNAs that serve as mRNAs for the structural proteins. Transmission of these viruses to new hosts is often facilitated by mechanical means, such as through pruning or grafting, and by specific insect vectors, particularly aphids and mealybugs, although some species may be transmitted by other means.

Betaflexiviruses are known to infect a wide range of plant species, including economically important crops and ornamental plants. Symptoms can vary greatly depending on the specific virus and host plant, but commonly include mosaic patterns, leaf distortion, stunting, and reduced yield. Some betaflexiviruses can cause significant damage to agricultural production. Control strategies often involve the use of resistant plant varieties, sanitation practices to prevent mechanical spread, and management of insect vectors.