title: Phloem restriction of viroids in three citrus hosts is overcome by grafting with Etrog citron: potential involvement of a translocatable factor.
abstract: Viroid systemic spread involves cell-to-cell movement from initially infected cells via plasmodesmata, long-distance movement within the phloem and again cell-to-cell movement to invade distal tissues including the mesophyll. Citrus exocortis viroid (CEVd), hop stunt viroid, citrus bent leaf viroid, citrus dwarfing viroid, citrus bark cracking viroid and citrus viroid V remained phloem restricted when singly infecting Citrus karna, Citrus aurantium and Poncirus trifoliata, but not Etrog citron, where they were additionally detected in mesophyll protoplasts. However, when CEVd-infected C. karna was side-grafted with Etrog citron--with the resulting plants being composed of a C. karna stock and an Etrog citron branch--the viroid was detected in mesophyll protoplasts of the former, thus indicating that the ability of Etrog citron to support viroid invasion of non-vascular tissues was transferred to the stock. Further results suggest that a translocatable factor from Etrog citron mediates this viroid trafficking.
authors.affiliation: Departamento de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Apartado Oficial, 46113 Moncada, Valencia, Spain.|Iran Citrus Research Institute, 46915-335 Ramsar, Iran.
authors.forename: Seyed Mehdi
authors.initials: SM
authors.lastname: Bani-Hashemian
authors.affiliation: Departamento de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Apartado Oficial, 46113 Moncada, Valencia, Spain.|José Morera S.L., Pl. Almansa 1-1°, 46001 Valencia, Spain.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Pensabene-Bellavia
authors.affiliation: Departamento de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Apartado Oficial, 46113 Moncada, Valencia, Spain.
authors.forename: Nuria
authors.initials: N
authors.lastname: Duran-Vila
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas (UPV - CSIC), 46022 Valencia, Spain.|Departamento de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Apartado Oficial, 46113 Moncada, Valencia, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Serra
mesh_terms: D001947:Breeding; D002957:Citrus / Q000145:classification / Q000235:genetics / Q000378:metabolism / Q000821:virology*; D058507:Host Specificity; D052585:Phloem / Q000821:virology*; D010935:Plant Diseases / Q000235:genetics / Q000821:virology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D014772:Viroids / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*
chemical_list: D010940:Plant Proteins