Citrus leprosis disease is associated with several viruses
Citrus leprosis (EPPO A1 List) is a viral disease of citrus crops causing severe defoliation, girdled limbs, premature fruit drops, twig dieback, reduction in both fruit quality and yield, as well as tree death. It is an emerging disease which is currently spreading in the Americas. Citrus leprosis is a complex disease, transmitted by mites in the genus Brevipalpus. Disease symptoms are associated with two taxonomically distinct classes of viruses:
- positive-sense RNA and cytoplasmic viruses: Citrus leprosis virus C (Cilevirus, CiLV-C), Citrus leprosis virus C2 (Cilevirus, CiLV-C2) and Hibiscus green spot virus 2 (Higrevirus, HGSV-2);
- negative-sense RNA and nuclear viruses: Citrus leprosis virus N (Dichoravirus, CiLV-N), Citrus necrotic spot virus (Dichoravirus, CiNSV).
According to the literature, the geographical distribution of these viruses is as follows (the cytoplasmic type viruses being the most prevalent and widely distributed):
CiLV-C: Argentina, Belize, Bolivia, Brazil, Colombia, Costa Rica, Guatemala, Honduras, Mexico, Nicaragua, Panama, Paraguay, Uruguay, Venezuela.
CiLV-C2: Colombia.
CiLV-N: Brazil, Colombia, Mexico, Panama.
CiNSV: Colombia, Mexico.
HGSV-2: USA (Hawaii).
These five viruses have been recorded on the following host plants:
CiLV-C: Citrus sinensis, C. paradisi, C. reticulata. Also found in Swinglea glutinosa and Commelina benghalensis.
CiLV-C2: C. sinensis. Also found in Dieffenbachia sp., Hibiscus rosa-sinensis and Swinglea glutinosa.
CiLV-N: C. aurantiifolia, C. aurantium, C. latifolia, C. limetta, C. limon, C. paradisi, C. reticulata, C. sinensis.
CiNSV: C. aurantium, C. paradisi, C. sinensis, C. tangerina.
HGSV-2: C. reticulata, C. sinensis, C. volkameriana. Also found in Hibiscus arnottianus and H. tiliaceus.
Sources
Cruz-Jaramillo JL, Ruiz-Medrano R, Rojas-Morales L, Lopez-Buenfil JA, Morales-Galvan O, Chavarin-Palacio C, Ramirez-Pool JA, Xoconostle-Cazares B (2014) Characterization of a proposed Dichorhavirus associated with the Citrus leprosis disease and analysis of the host response. Viruses 6, 2602-2622.
Roy A, Hartung JS, Schneider WL, Shao J, Leon G, Melzer MJ, Beard JJ, Otero-Colina G, Bauchan GR, Ochoa R, Brlansky RH (2015) Role bending: complex relationships between viruses, hosts, and vectors related to citrus leprosis, an emerging disease. Phytopathology 105(7), 1013-25.