Pepper necrosis

Pepper necrosis is a destructive viral condition primarily attributed to the Tomato Spotted Wilt Virus (TSWV) and other related viral agents. The disease acts systemically, colonizing the vascular tissues of the plant and inducing necrotic lesions, which eventually disrupt nutrient and water transport, leading to plant collapse.

The host range for this disease is extensive, encompassing various species of the Capsicum genus, such as bell and chili peppers. Furthermore, the virus frequently infects other solanaceous crops like tomatoes, eggplant, and potatoes, alongside numerous weed species that act as asymptomatic reservoirs for the virus.

Visual diagnostic signs include dark, sunken necrotic spots or rings on the foliage, stems, and fruits. Affected plants often exhibit stunted growth, chlorosis, and terminal dieback. In advanced stages, the systemic necrosis results in a bronze-like discoloration of the leaves, rendering the plant non-productive and unsightly.

The transmission of the disease is predominantly mediated by thrips, which acquire the virus while feeding and transmit it to healthy plants. Environmental conditions such as moderate temperatures and high humidity significantly enhance the life cycle of these vectors, facilitating rapid viral spread throughout a greenhouse or field.

Integrated pest management (IPM) is the most effective approach to mitigate pepper necrosis. Essential strategies include:

• rigorous control of thrips populations using insecticides and blue sticky traps;
• immediate rogueing and destruction of infected plants;
• implementation of strict sanitation protocols for equipment;
• selection of resistant cultivars where available.