Ageratum yellow vein Sri Lanka virus

Begomovirus agerasrilankaense is a plant pathogen belonging to the Geminiviridae family. Characterized by a single-stranded DNA genome, this virus causes significant systemic diseases in various plants, most notably within the Asteraceae family. It is recognized as a serious concern for both ornamental horticulture and agricultural production in affected regions.

The primary host for the virus is Ageratum conyzoides, where it induces characteristic symptoms. However, its host range extends to other species, including several vegetable crops. Due to the virus's ability to infect weeds, it can easily persist in the environment, making it difficult to eradicate completely from surrounding agricultural areas.

Key symptoms of the disease include distinct yellow vein clearing, interveinal chlorosis, and severe leaf curling. Infected plants exhibit stunted growth, reduced internode length, and overall physiological distress. These symptoms lead to reduced yield in vegetables and loss of aesthetic value in ornamental flowers, making the plants unsellable.

Transmission occurs primarily through the whitefly Bemisia tabaci. The insect acquires the virus while feeding on infected sap and transmits it to healthy plants. The efficiency of the virus spread is closely linked to the population density of the whitefly vector, which thrives in warm, humid conditions common in greenhouse environments.

Management and prevention focus on breaking the transmission cycle:

• implementing integrated pest management (IPM) to control whitefly populations;
• regular sanitation to remove infected weeds and host reservoirs;
• using fine-mesh netting in greenhouses to exclude vectors;
• adopting strict quarantine protocols for introducing new plant materials.