01822naa a2200193 a 450000100080000000500110000800800410001910000220006024501130008226000090019552012970020465000170150165000110151865300120152965300120154165300120155370000200156577300430158516464542023-05-30       1993    bl uuuu     u00u1 u    #d1 aFONSECA, M. E. N.  aFrench marigold (Tagetes patula)ba new xxperimental host of citrus exocortis viroid.h[electronic resource]  c1993  aFrench marigold (Tagetes patula L.) was found to be a new host of citrus exocortis viroid (CEVd) during a host range study of a Brazilian isolate of the viroid. Plants of marigold and of theree other common herbaceous hosts of CEVd-tomato (Lycopersicon esculentum Mill. 'Rutgers'), chrysanthemum (Chrysanthemum X morifolium Ramat.), and velvetplant (Gynura aurantiaca (Blume) DC.)-were slash-inoculated with a CEVd nucleic acid preparation (100 ng/ul) purified from citron tissues as described by Semancik and Weathers (2). The CEVd- and buffer-inoculated plants (negative controls) were kept in a greenhouse at 25-30 C. Typical symptoms of CEVd infection (epinastry and stunting) were observed in tomato, chrysanthemum, and velvetplant 30 days later, whereas marigold plants did not show any diagnostic symptom. CEVd infection was confirmed by dot blot hybridization assay with CEVd-RNA transcripts (riboprobes). In comparative tests using return-PAGE (1), marigold extracts produced more intense bands, as judged visually, than did extracts from tomato, chrysanthemum, and velvetplant. The viroid was not detected in the negative controls. Our findings suggess that marigold may be used as an additional test plant for CEVd indexing and also to multiply this viroid for analytical purposes.  aHibridação  aVírus  aPlantas  aTecidos  aViroide1 aKITAJIMA, E. W.  tPlant disease, September 1993, p. 953.