The majority of farmers in the study, ranging from 62% of tomato growers in Thailand to 92% of chili growers in Vietnam, had observed virus disease symptoms in their crop. Growers in India and Thailand, but not in Vietnam, perceived that the severity of the damage had increased during the three most recent years. Farmers in Thailand and Vietnam were generally unable to tell that the disease symptoms were caused by a virus, and knowledge about the role of insect vectors in the transmission of the disease was minimal. Farmers in
Tamil Nadu have received more information about virus diseases and their mode of transmission, and were better able to distinguish
between symptoms caused by viruses and those caused by other
diseases. Lacking knowledge and understanding, farmers tried to
control disease symptoms by applying pesticides, the use of which
was found to be high, particularly for tomatoes in Thailand.