CaMV

Cauliflower Mosaic Virus (CaMV) is a plant virus that infects members of the Brassicaceae family, including cauliflower, cabbage, broccoli, and mustard. It is a member of the Caulimoviridae family and is notable for being one of the first plant viruses to have its genome fully sequenced. CaMV is a double-stranded DNA virus, which is relatively rare among plant viruses, as most are RNA viruses.

Overview

CaMV is transmitted between plants by insect vectors, specifically aphids, in a non-persistent manner. This means that the aphids can acquire the virus by feeding on an infected plant and then transmit it to a healthy plant, but the virus does not persist for long within the aphid. The virus can also be transmitted through mechanical transmission, such as when plants are wounded or during agricultural practices.

Genome and Structure

The CaMV genome is circular and consists of approximately 8,000 base pairs. It encodes for seven known genes, which are involved in various functions including virus replication, assembly, and movement within the host plant. The virus particles are icosahedral in shape and have a diameter of about 50 nm.

Pathology

Infection with CaMV can cause a range of symptoms in host plants, including stunting, leaf curling, and the appearance of mosaic patterns on the leaves, from which the virus gets its name. These symptoms can lead to reduced crop yields in agriculturally important species. However, the severity of the symptoms can vary depending on the strain of the virus, the species of the host plant, and environmental conditions.

Economic Importance

CaMV has significant economic importance due to its impact on crops within the Brassicaceae family, many of which are of global agricultural significance. Management of CaMV infection includes the use of resistant plant varieties, control of aphid populations, and good agricultural practices to avoid mechanical transmission.

Biotechnological Applications

Interestingly, CaMV has also been utilized in biotechnology and genetic engineering. The CaMV 35S promoter, derived from the virus, is one of the most commonly used promoters in plant genetic engineering. It is known for its ability to drive high levels of gene expression in various plant tissues.

Control and Prevention

Control measures for CaMV include the use of virus-free seeds, control of aphid vectors through insecticides or biological control agents, and the removal and destruction of infected plants. Crop rotation and the use of resistant cultivars are also effective strategies for managing CaMV infection.