Orchid fleck symptoms may be caused naturally by two different viruses transmitted by Brevipalpus

• Published in: Journal of general plant pathology : JGPP Vol. 75; no. 3; pp. 250 - 255
• Main Authors: Kubo, K.S.(Universidade de Sao Paulo (Brazil)), Freitas-Astua, J, Machado, M.A, Kitajima, E.W
• Format: Journal Article
• Language: English
• Published: Japan Springer Japan 01.06.2009; Springer Nature B.V
• Subjects: Agriculture; Biomedical and Life Sciences; BREVIPALPUS; CITOPLASMA; Citrus leprosis virus; CYTOPLASM; CYTOPLASME; DISEASE TRANSMISSION; Flowers & plants; Insects; Life Sciences; Microbiology; NOYAU CELLULAIRE; NUCLEO; NUCLEUS; Orchid fleck virus; ORCHIDACEAE; Pathogens; Plant Pathology; Plant species; PLANT VIRUSES; SINTOMAS; Solanum; SYMPTOME; SYMPTOMS; TRANSMISION DE ENFERMEDADES; TRANSMISSION DES MALADIES; Viral and Viroid Diseases; VIROSE; VIROSES; VIROSIS; VIRUS DE LAS PLANTAS; VIRUS DES VEGETAUX; Orchid fleck virus; transmitted virus; Nuclear type; Cytoplasmic type
• ISSN: 1345-2630; 1610-739X
• DOI: 10.1007/s10327-009-0167-z

Brevipalpus-transmitted viruses (BTV) cause chlorotic, necrotic and/or ringspot lesions in leaves and stems of orchids, citrus, coffee and several other plant species. There are two different types of BTVs, the nuclear and the cytoplasmic, based on maturation locale in the cell and particle morphology. The orchid fleck virus (OFV) is a BTV that infects orchids. Its short rodlike particles are 32-40 nm in diameter, 100-150 nm in length. OFV is found in the nucleus and is associated with intranuclear electronlucent viroplasms. In 1999, transmission electron microscopy analysis revealed a distinct type of virus causing orchid fleck symptoms. The bacilliform particles, 70-80 nm in diameter and 110-l20 nm in length, induced electron-dense viroplasm inclusions in infected cells and resembled the cytoplasmic type associated with BTV, such as the citrus leprosis virus C. Our objective in the present study was to verify whether the cytoplasmic type virus found in orchids could be amplified using primers for other cytoplasmic BTVs, such as CiLV-C and Solanum violaefolium ringspot virus (SvRSV). Additionally, we aimed to differentiate the two BTVs found in orchids: the nuclear and the cytoplasmic types of OFV using microscopy and molecular and serological tools. This virus was not amplified by the CiLV-C and SvRSV primers, and neither the molecular nor the serological tools available to the OFV diagnosis reacted with it, demonstrating that they are definitely different viruses.