Tomato geminiviruses in Brazil
Tomato golden mosaic geminivirus was reported in Brazil more than 20 years ago, but until recently tomato-infecting geminiviruses had no economic significance. Since 1994, a sharp increase of geminivirus-like symptoms has been observed in several areas in Brazil. This occurred simultaneously with the appearance of the B biotype of Bemisia tabaci (EPPO A2 quarantine pest). Geminiviruses have been isolated from symptomatic tomato plants in the Federal District, two different areas of Minas Gerais and in Pernambuco. These plants showed a variety of symptoms (e.g. yellow mosaic, severe leaf distortion, downward leaf curling and epinasty). Whitefly populations were high in all sampled fields. In some fields, and particularly in Pernambuco, incidence of symptoms was close to 100% and no tomato of commercial value could be harvested. By using molecular techniques (PCR and comparison of amplified fragment sequences), it was felt that at least six different geminiviruses were present. These viruses are most closely related to tomato golden mosaic, bean golden mosaic and tomato yellow vein streak geminiviruses. However, homologies were less than 80 % for the fragments compared. Further studies are needed on the biological and molecular characterization of these geminiviruses
Ribeiro, S.G.; de Avila, A.C.; Bezerra, I.C.; Fernandes, J.J.; Faria, J.C.; Lima, M.F.; Gilbertson, R.L.; Maciel-Zambolim, E.; Zerbini, F.M. (1998) Widespread occurrence of tomato geminiviruses in Brazil, associated with the new biotype of the whitefly vector.
Plant Disease, 82(7), p 830.