Identification of Viroids in Citrus Orchards in Tunisia

Abstract

The cachexia disease caused by specific variants of Citrus viroid II (CVd-II) has been identified in commercial orchards of Cassar Clementine and common mandarin in Tunisia. Since commercial cultivars are usually grown on sour orange rootstock in Tunisia, exocortis symptoms have not been observed. Within the framework of the National Program for the selection of varieties free of virus and virus-like agents, indexing for citrus viroids allowed the identification of additional viroids in tolerant scion/rootstock combinations. In addition to CVd-II and Citrus exocortis viroid, we identified Citrus viroid I, Citrus viroid III and Citrus viroid IV.