Catharanthus mosaic virus

Catharanthus mosaic virus, scientifically classified as Potyvirus catharantessellati, is a viral pathogen belonging to the Potyvirus genus. This plant disease systemically infects hosts, disrupting normal physiological processes such as photosynthesis and nutrient translocation, which significantly impacts the health and aesthetic quality of the plants.

The primary host for this virus is the Madagascar periwinkle (Catharanthus roseus). It predominantly affects nursery-grown plants and those cultivated in greenhouse environments. While it primarily targets Catharanthus species, its presence within a collection poses a significant risk to the entire biodiversity of susceptible ornamental plants grown in the vicinity.

Symptoms are characteristic of potyviral infections and include mosaic patterns, chlorotic mottling, leaf curling, and stunted growth. The foliage may appear crinkled or distorted, and affected plants often show a reduction in both the size and quantity of flowers. In severe cases, chlorosis becomes more intense, leading to significant decline in plant vigor.

Transmission of Potyvirus catharantessellati is facilitated mainly by aphid vectors in a non-persistent manner. The virus is acquired and transmitted within seconds or minutes of aphid feeding. Furthermore, mechanical transmission is a major factor in horticultural settings, occurring through contaminated pruning tools, hands, or direct contact between healthy and infected foliage during cultivation practices.

Management of this viral disease relies entirely on prevention and sanitation strategies since there are no chemical treatments available to cure systemic plant viruses. Key measures include:

• Strict rogueing of symptomatic plants.
• Rigorous control of aphid populations using biological or chemical means.
• Sterilization of pruning tools using appropriate disinfectants.
• Use of virus-indexed, certified disease-free propagation material.