Sweet potato cavemovirus

The causative agent of the disease is Cavemovirus collusipomeae, a virus belonging to the genus Cavemovirus of the Caulimoviridae family. This double-stranded DNA virus causes systemic infection in plant tissues. In agricultural practice, it is considered a significant pathogen that can substantially reduce yield and quality, often exhibiting symptoms that can be mistaken for nutrient deficiencies or other stressors.

The primary host for this virus is the sweet potato (Ipomoea batatas). The pathogen is well-adapted to tropical and subtropical growing conditions. However, the international trade of plant material poses a constant risk, as the virus can be introduced into new regions, potentially causing outbreaks in areas where previously the pathogen was not detected, thereby threatening local agricultural sustainability.

Symptoms of the infection typically include mosaic patterns on leaves, vein yellowing, and general chlorosis. Depending on the viral strain and the host cultivar's susceptibility, affected plants may show leaf deformation, stunted growth, and a reduction in overall biomass. These physiological changes significantly impede photosynthesis and result in a lower yield of tubers, which is the primary concern for commercial farmers.

Transmission within agroecosystems occurs mainly through the use of infected vegetative cuttings and storage roots. Furthermore, insects such as aphids act as vectors, mechanically transferring viral particles during feeding. The ability of the virus to persist in vegetative propagation stock makes it a persistent challenge in cultivation, as the pathogen is passed from generation to generation if infected stock is not discarded.

Effective management strategies rely on rigorous quarantine measures and the exclusive use of virus-indexed, certified planting material. Essential preventive steps include:

• Establishing nurseries in protected environments.
• Regular phytosanitary inspection and roguing of symptomatic plants.
• Implementation of insect control programs to limit the population of vectors.
• Usage of tissue culture techniques to produce clean plant stocks.