Tomato Spotted Wilt virus is a devastating disease because it has such a large host range and has an impact worldwide. The virus infects 174 known plant species and has cost the green industry greatly.
The virus was first found in 1919 in Australia and it is not a seed born disease. It is thought that the disease was spread through cuttings that were shipped from one country to the next. This virus is very hard to control because it has 6 different strains and is very resistant to pesticides. It is an RNA virus that is membrane bound and has spherical particles.
The virus Tosporius, in the family Bunyaviridae has many hosts including; tomato, tobacco, potato, lettuce, pepper, eggplant, cauliflower, celery, endive, spinach, pea, dahlia, sweet pea, zinnia, nasturtium, poppy, lily, petunia, orchid, chrysanthemum, aster, salpiglossis, cineraria, gloxinia, bindweed, nettle, mallow, and chickweed. The disease is very hard to detect because you do not see the symptoms until it is too late.
The symptoms of the virus on a tomato plant is curling leaves, off color foliage somewhat bronze color, dark brown streaks on the main branch, and the fruit have white or yellow rings with raised bumpy marks on it.
Tomato spotted wilt virus is transmitted by thrips. The four main thrips that carry the virus are western flower thrips, tobacco thrips, onion thrips, and tropical thrips. The most economic threat it has is the impact it has on the greenhouse industry. The thrips that attack the greenhouse and ornamental industry are the western flower thrips. In 1989 the thrips were first found to be attacking New Guinea Impatiens which cause black stem dieback and cause the plant to collapse. The impatiens also get brown leaf spots and a distorted leaf when infected with the virus. It...