34. FIRST REPORT OF CITRUS VARIEGATION VIRUS IN SWEET LIME AS COFFEE SHADE IN THE CENTRAL VALLEY IN SAN JOSÉ, COSTA RICA

Since 2005, symptoms resembling those of Citrus variegation virus (CVV) were observed in old sweet lime trees (Citrus limettioides Tan.) used as coffee shade in the Central Valley in San Jose, Costa Rica. The symptoms include leaf flecking, mosaic, malformation and dwarfing. This disease was transmitted by grafting to sweet orange “Valencia” (Citrus sinensis), cidro Etrog and sweet lime under greenhouse conditions. Symptoms were stronger in sweet lime all year long, but in sweet orange and cidro were asymptomatic when the temperature was high. To confirm CVV, reverse transcription polymerase chain reaction (RT-PCR) was used to detect virus in young leaves from sweet lime trees. Fresh tissue with CVV was used as positive control from trees obtained from the USDA, Riverside, California. Furthermore, the sequence obtained (663nt) analyzed by Blastn algorithm showed 97% homology with CVV RNA 3 (AF434912.1). For additional CVV diagnosis, small scale virus purification was carried out and isometric particles (26 to 32 nm) were seen under the electron microscope (H7100). To our knowledge, this is the first report of the presence of CVV in Costa Rica affecting sweet limes as shade in coffee plantations.