Tomato mottle

Tomato mottle is a severe viral disease caused by the Tomato mottle virus (ToMoV), a member of the Begomovirus genus. This plant pathogen poses a significant threat to agriculture, primarily in warm climates where its insect vectors thrive throughout the year, leading to rapid disease transmission within fields.

The primary vector for the transmission of this virus is the silverleaf whitefly (Bemisia tabaci). Once the whitefly acquires the virus by feeding on an infected host, it becomes a lifelong carrier. The virus is transmitted in a persistent, circulative manner, meaning that once the vector picks up the virus, it can infect healthy plants for the remainder of its lifespan.

The host range of Tomato mottle includes a variety of solanaceous crops. Tomatoes are the most severely affected, but the virus can also colonize peppers and certain wild solanaceous weeds. These weeds often act as silent reservoirs, allowing the virus to survive between growing seasons when the primary crop is absent.

Symptoms of the disease are characterized by distinct leaf mottling, interveinal chlorosis, and severe upward leaf curling. Infected plants exhibit stunted growth, reduced internode length, and a bush-like appearance. As the infection progresses, fruit set is greatly diminished, and the fruits that do develop are often stunted, deformed, and show poor ripening quality.

Management of the virus is difficult because there is no cure for infected plants. Therefore, control focuses on preventing infection through integrated pest management.

• Rigorous control of whitefly populations using biological and chemical control agents.
• Removal of infected plants immediately upon the appearance of symptoms to reduce inoculum levels.
• Use of reflective mulches and row covers to deter whitefly landing.
• Strict sanitation practices to eliminate weeds that host the virus or the vector.
• Selection of resistant or tolerant cultivars developed for specific regional pressures.