Geminiviruses in Trinidad and Tobago
In Trinidad and Tobago, since 1989 severe leaf mottling, leaf curling and leaf size reduction have been observed in tomato fields suggesting the presence of geminiviruses. At first this was observed in the north of Trinidad but the disease spread throughout the country and is now a severe threat to the tomato industry. Similar virus-like infection are also observed in other agricultural crops and weeds in the vicinity of tomato fields. In 1995, in 12 agricultural locations, 7 crops and 8 weed species were tested for the presence of whitefly-transmitted geminiviruses by using molecular techniques (dot blot hybridization, PCR, comparison of amplified sequences with other known geminiviruses). Whitefly-transmitted geminiviruses were found in all locations studied, on 10 of the 15 plant species: Lycopersicon esculentum (tomato), Capsicum annuum (sweet pepper), Capsicum frutescens (pepper), Phaseolus vulgaris (bean), Abelmoschus esculentum (okra) and the following weeds: Alternanthera tenella, Desmodium frutescens, Euphorbia heterophylla, Malva alceifolia, Sida acuta. The geminiviruses found were closely related to potato mosaic begomovirus from Venezuela and tomato yellow leaf curl begomovirus (EPPO A2 quarantine pest) from Panama. Mixed infections of a virus related to potato mosaic begomovirus and a virus related to pepper huasteco begomovirus were found in pepper, sweet pepper, okra, Alternanthera tenella, Desmodium frutescens, Euphorbia heterophylla, and in one tomato sample. The EPPO Secretariat had previously no data on the occurrence of tomato yellow leaf curl begomovirus in Trinidad and Tobago.
Sources
Umaharan, P.; Padidam, M.; Phelps, R.H.; Beachy, R.N.; Fauquet, C. M. (1998) Distribution and diversity of geminiviruses in Trinidad and Tobago.
Phytopathology, 88(12), 1262-1268.