Dioscorea aureusvirus

Dioscorea aureusvirus (Aureusvirus dioscoreae) is a viral plant pathogen that primarily affects species of the genus Dioscorea, commonly known as yam. As a member of the Tombusviridae family, this virus acts as a systemic pathogen, disrupting the physiological functions of the host plant and leading to a significant reduction in tuber quality and yield potential.

The primary hosts of this virus are agricultural yam varieties, which are essential staple crops in tropical and subtropical regions. The susceptibility of these crops to viral infections necessitates a deep understanding of pathogen behavior to ensure food security and sustain the livelihoods of local farming communities who rely on these tubers as a primary caloric source.

The diagnostic symptoms of the infection include leaf chlorosis, which manifests as a distinctive golden mosaic pattern on the foliage. Infected plants typically show signs of developmental stress, such as stunted shoot growth, leaf deformation, and a visible reduction in the overall vigor of the plant, which often results in smaller, lower-quality harvested tubers.

The transmission of this virus is primarily facilitated by the use of infected tubers as planting material, which allows the virus to propagate through vegetative multiplication. Additionally, mechanical transmission during agricultural activities, such as pruning or weeding with shared tools, and potentially through insect vectors, contributes to the rapid spread of the disease across fields.

Effective management and prevention require strict adherence to phytosanitary protocols. This includes the exclusive use of virus-indexed, certified clean planting materials and the prompt roguing of symptomatic plants to minimize the inoculum load in the field. Sanitation of agricultural tools after every use is essential to prevent the mechanical transfer of the virus between individual plants.

• Regular inspection of crops during the vegetative stage.
• Implementation of rigorous weed control to eliminate alternative virus hosts.
• Isolation of new planting materials to ensure they are free from viral symptoms.