Phytoplasma and spiroplasma diseases in open-field crops in Israel

During 2009 - 2011, symptoms of curling, yellow and purple discoloration of leaves, stunting of shoots, and formation of bunchy, fibrous secondary roots were observed in several ornamental crops, carrot, celery, and parsley fields located in several production areas of Israel. Incidence of disease was almost 20-80% in individual affected fields. Moreover, the observed symptoms resembled those caused by Spiroplasma citri in carrots affected by the carrot purple leaf disease, recently reported in United States and in Spain. Analyses revealed that high percentage of symptomatic plants tested positive for S. citri. Some of the plants were double infected by S. citri and a phytoplasma. Leafhopper species known to vector phytoplasmas and/or spiroplasmas, have been trapped in several locations in Israel. To our knowledge, this is the first report of S. citri associated with the 'yellow disease' syndrome in open-field crops in Israel.