Causal Agent:
Tobacco Etch Virus (TEV).

Vector:
Aphids (Myzus persicae and others).

Distribution:
North and South America

Symptoms:
Disease symptoms have been reported on tomato that range from a mild mottling and slight distortion of the foliage to a severe mottling and crinkling of the foliage. Fruit are often reduced in size, mottled and misshapen. Usually, the earlier the plant is infected, the greater the effects on plant stunting and yield.

Mild mottling and distorted foliage symptoms.

Conditions for Disease Development:
Many species of weeds can act as a host for the virus, and it can be transmitted by at least 10 species of aphids. TEV is transmitted in a non-persistent manner by virus-carrying aphids moving into tomato fields from nearby solanaceous weeds, peppers and other tomato fields which are already infected. Secondary infection may be caused by aphids, or the virus may be mechanically transmitted through staking, pruning or handling of infected plants.

Control:
Removing weed hosts which may harbor the virus is important. Avoid locating tomato productions near peppers crops because peppers can be a major source of the virus. Reducing the spread of the disease by controlling the aphid vector population is very difficult and generally not practical.