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.