Mosaic Disease of Brassica sp. In Thailand

Abstract

Turnip mosaic virus was isolated from Brassica chinensis (Jusl.) var parachinensis (Bailey) Tsen and Lee. The virus is a member of the Potyvirus group with a length of 732.35 mm. It was transmitted to 26 species of plant in 9 families. Five species of aphids namely Aphis craccivora Koch., A. glycines Mats, A. gossypii Glov., Lipaphis erysimi Kalt. And Myzus pericae Sulz. Transmitted the virus at 40, 10, 60, 5 and 70 percent respectively. Its dilution end point was between 1 : 1,000-1 : 2,000, thermal inactivation point between 55-60 C and longevityinvitro between 3-4 days. Purified virus suspension was obtained utilizing Tomlinson’s method. The virus banded at 2 cm. from the meniscus and react strongly with Turnip mosaic virus antiserum from the Netherland & Japan.