Tobacco etch virus

Tobacco etch virus (TEV) is a destructive plant pathogen classified under the Potyvirus genus in the Potyviridae family. It is a single-stranded RNA virus that causes significant economic losses by infecting a variety of commercially important vegetable and field crops.

The primary hosts of this virus are members of the Solanaceae family. Crops such as tobacco, tomatoes, peppers, potatoes, and eggplants are highly susceptible to infection. Furthermore, many common weeds act as natural reservoirs for the virus, facilitating its persistence and spread within agricultural areas.

Typical symptoms manifest as distinctive etching or light-colored patterns on the leaves, followed by mosaic patterns, vein clearing, leaf distortion, and stunted growth. Infected plants often produce low-quality fruits that are misshapen or necrotic, rendering them unsuitable for market distribution.

The transmission of the virus occurs primarily through non-persistent vectors, specifically various species of aphids like Myzus persicae. When an aphid feeds on an infected plant, it picks up the virus and can transmit it to a healthy plant within seconds. Mechanical transmission, occurring through contaminated equipment or handling during pruning and harvesting, also contributes to the spread.

• Manage aphid populations using targeted insecticide programs.
• Implement strict sanitation measures to remove reservoir weeds.
• Use certified virus-free seeds and transplants.
• Plant resistant or tolerant cultivars whenever available.
• Disinfect agricultural tools regularly to prevent mechanical transmission.

The damage caused by TEV is substantial, often leading to reduced photosynthesis and physiological stress in host plants. Because there are no therapeutic treatments to eliminate the virus once a plant is infected, management strategies must focus entirely on preventative measures to limit the virus's ability to enter and move through the field.