Tomato Spotted Wilt Virus

Tomato spotted wilt virus is transmitted by various species of thrips, including the western flower thrips, the onion thrips, and the chili thrips. Tomato spotted wilt virus also infects the thrips vector. Nymphs that acquire the virus by feeding on infected plants will retain the ability to transmit it for the remainder of their lives. Tomato spotted wilt virus cannot be passed from infected females through the eggs.

Leaf infected by TSWV

The virus has an extremely wide host range, including many weeds and ornamentals as well as crop hosts. It is one of the few plant viruses with a host range that includes tomatoes, peppers, and onions.

Symptoms and Signs:

Plants infected with Tomato spotted wilt virus exhibit bronzing of the upper sides of young leaves, which later develop distinct, necrotic spots. Leaves may be cupped downward. Some tip dieback may occur. On ripe fruit, chlorotic spots and blotches appear, often with concentric rings.

TSWV symptoms on tomato fruits

Management:

It should be noted that once the plant is infected with Tomato spotted wilt virus, it has no known cure. However, the following measures can be undertaken to control and manage it:

Plant resistant varieties in the disease-prone areas e.g Big Rock F1 for tomato; Ilanga F1 and Balta F1 for the pepper
Use virus- and thrips-free transplants
Avoid planting near crops infected with Tomato spotted wilt virus
Consider removing infected plants as soon as the symptoms are observed
Control weeds in and around fields.
Promptly remove and destroy old host crops after harvest.
Control and manage thrips. For more information on thrips, visit https://agropests.co.ke/blog/thrips

TWSV in pepper