Geminivirus

Geminiviruses are a genus of small, single-stranded DNA viruses in the family Geminiviridae. These viruses are known for their distinctive geminate (twin) particles, which are composed of two joined virions. They infect a wide range of plant species, causing significant agricultural damage and economic losses globally. Geminiviruses are transmitted by insect vectors, primarily whiteflies, leafhoppers, and thrips, which acquire the virus from infected plants and then transmit it to healthy ones during feeding.

The genome of geminiviruses consists of one or two circular single-stranded DNA molecules. They replicate within the nucleus of host plant cells using a rolling-circle replication mechanism. Upon infection, the virus injects its DNA into the plant cell, which is then transported to the nucleus and transcribed into viral proteins. These proteins are responsible for replicating the viral DNA and assembling new virions.

Symptoms of geminivirus infection vary depending on the specific virus and host plant but often include leaf curling, yellowing (chlorosis), stunting, mosaic patterns, and reduced fruit production. Some geminiviruses can also cause more severe symptoms such as leaf deformation and vein thickening. Control strategies focus on managing the insect vectors through insecticides, using resistant plant varieties, and implementing cultural practices like crop rotation and sanitation.