TRANSMISIÓN DEL VIRUS TYLCV A DIFERENTES MATERIALES DE TOMATE (Solanum lycopersicon L.) MEDIADA POR EL BIOTIPO B DEL COMPLEJO Bemisia tabaci (Gennadius)

TYLCV transmission to different tomato accessions (Solanum lycopersicon L.) mediated by Bemisia tabaci (Gennadius) During December 2006- February 2007 transmission of TYLCV to tomato potted plants mediated by Bemisia tabaci (Biotype B) was evaluated in insect proof cages. Tomato plants of Rio Orinoco hybrid (ROH), Rio Grande hybrid (RGH), Cid hybrid (CH) and Rio Grande variety (RGV) were exposed for 48 hours in individual cages to whiteflies raised either on viral infected tomato plants or healthy cotton plants. Thereafter, plants were observed daily for symptoms detection. Presence of Begomovirus in source plants was determined by PCR amplifying the 550 and 851 bp fragments of the central region of the gene coding for the viral coat protein. The sequences of the amplified fragments have 99% and 96% identity respectively with a TYLCV isolate. For experimental plants only presence of Begomovirus was determined amplifying by PCR the 550 bp fragment. ROH, RGH and RGV showed symptoms 11.3±1.4, 11.2±1.5 and 11.2+1.4 days post exposure period to the whiteflies, respectively. No symptoms were observed on CH tomato plants despite detection of Begomovirus by PCR. Symptomatic plants reached 100% for RGH and RGV, as well as 95% for ROH. These results suggest specific resistance of CH tomato plants to TYLCV infection. Additional key words: Resistant cultivars, vector, Begomovirus, Geminiviridae