Iris yellow spot virus

Orthotospovirus iridimaculaflavi is a viral pathogen belonging to the genus Orthotospovirus within the family Tospoviridae. This pathogen is an obligate parasite that primarily infects ornamental plants, with a focus on members of the Iridaceae family. As a tospovirus, it is recognized for its complex transmission cycle and broad host range, posing a significant challenge to both greenhouse and field-based agricultural production systems.

The primary hosts for this virus are irises. The infection causes systemic physiological disruptions, which manifest as the plant matures. Beyond the primary hosts, the virus may also infect various alternative plant species in close proximity, which serves as a reservoir for the pathogen and complicates long-term management strategies and quarantine protocols.

Symptoms of the disease are typically characterized by chlorotic spots, streaks, and rings on the foliage. As the viral infection progresses, plants exhibit symptoms such as leaf deformation, stunted growth, and a marked decline in overall aesthetic and commercial value. In severe cases, tissues undergo necrosis, leading to premature wilting and death of the plant's aerial parts.

The transmission of the virus within agroecosystems is predominantly mediated by specific insect vectors, most notably thrips. These vectors acquire the virus while feeding on infected plant sap and transmit it to healthy plants during subsequent feeding events. Greenhouse environments with high temperature and humidity levels are particularly conducive to the rapid proliferation of thrips, facilitating the widespread transmission of the virus.

Effective management requires an integrated pest management (IPM) approach. Key strategies include the exclusive use of virus-free planting stock, rigorous weed control to eliminate alternative hosts, and regular monitoring for thrips populations. Systemic insecticides are recommended for vector suppression. If symptoms are identified, prompt roguing and proper disposal of infected plants are essential to mitigate the spread of the disease to healthy stock.