Tomato spotted wilt virus TSWV Taxonomic position Negative

Tomato spotted wilt virus (TSWV)

Taxonomic position Negative single strand RNA virus (-ss. RNA). Family : Bunyaviridae Genus : Tospovirus

Principal Hosts Tomatoes, peppers, potatoes, celery, eggplant , peanuts, lettuce, pineapple, cucurbit, tobacco, many legumes and ornamental crops

Symptoms 1) On tomatoes, plants show bronzing, curling, necrotic streaks and spots on the leaves. 2) Dark-brown streaks also appear on leaf petioles, stems and growing tips. 3) The plants are small and stunted as compared with healthy plants. 4) The ripe fruit has distorted shape and shows pale red and yellow ring areas on the skin. Sometimes, affected plants are killed by severe necrosis.

Usual means of spread ØTSWV is spread by tiny insects called thrips , which pick up the virus by feeding on infected plants. ØIf the virus and the thrips are present, the severity of the disease depends on the weather. ØTSWV is not seed-transmitted. Ødisease conditions : warm temperatures and high thrips population.

Control §The presence of thrips in the crops should be monitored using yellow sticky cards. §If the disease appears in a crop, infected plants should be destroyed immediately and the house treated with insecticide against thrips. §Using green houses. § Insecticides are most effective when applied in the morning , when the thrips are most active.