Affected stems are brittle and appear brown internally. TMV can reduce size and number of fruit produced. The earlier a plant becomes infected, the greater the loss. Fruit usually do not show any malformation. Occasionally, mottling, bronzing, and internal browning of fruit occur.
Internal browning is evident on mature but unripened fruit.
Persistence And Transmission. TMV is a very stable, persistent virus that is readily spread by human activities. TMV can be a severe problem during production of tomato transplants in greenhouses. Handling plants during standard production practices such as transplanting, tying, and pruning can effectively spread the virus. The virus can survive in plant debris for varying periods, depending on soil moisture.