Severe yellowing outbreaks in tomato in Spain associated with infections of Tomato chlorosis virus

Since 1997, yellowing disease outbreaks have occurred in tomato (Lycopersic on esculentum) crops in southern Spain. The outbreaks were associated with high populations of the whitefly Bemisia tabaci. Symptoms consisted mainly of interveinal yellowing that developed initially on lower leaves and then progressed to the upper part of the plant. Affected plants were less vigoro us and yielded less due to reduced fruit growth and delayed ripening. Durin g 1998 and 1999, the yellowing disease was widespread and occurred at high incidences in the Malaga province. The disease agent was readily transmissi ble from tomato to tomato by B. tabaci biotype Q. Samples from symptomatic tomato plants were analyzed and shown to be infected with Tomato chlorosis virus (ToCV) (genus Crinivirus, family Closteroviridae). This is the first report of ToCV epidemics in Europe.