Detection of Cymbidium mosaic virus (CymMV) and Odontoglossum ringspot virus (ORSV) from orchids in Mexico
Por:
López-Hernández M.S., Palacios-Popo P.E., de la Torre-Almaraz R.
Publicada:
1 jul 2014
Resumen:
In a field inspection of commercial greenhouse orchids in 2011 in the state of Morelos, plants were observed to exhibit damage in the form of chlorotic mottle, faint yellow stripes and ring-shaped chlorotic and necrotic spots. Damaged leaves were collected from plants of the genera Brassia, Brassocattleya, Cattleya, Encyclia, Epidendrum, Guariathe, Laelia, Oncidium, Shomburghia, Vainilla and Xilobium. Viral protein serological detection tests (double antibody sandwich enzyme-linked immunosorbent assays, DAS-ELISA) were done with specific antiserums for diverse viruses that affect orchids. At least one plant of each genus had Cymbidium mosaic virus (CymMV; Potexvirus) and Odontoglossum ringspot virus (ORSV; Tobamovirus) in individual or mixed infections. Encyclia and Laelia plants had the highest incidence of infection by both viruses. The electrophoretic pattern of the CymMV genome was determined in polyacrylamide gels (PAGE) with double chain viral RNA from the samples that were positive in the DAS-ELISA serological assays. Identity of CymMV and ORSV was confirmed by direct sequencing and by cloning products different from the reverse transcriptase linked to PCR (RT-PCR) final point with degenerated oligonucleotides, which amplify two consensus regions of the replicase gene (RdRp) of the genus Potexvirus, and specific oligonucleotides, which amplify a conserved region of the capsid protein gene (CP of CymMV and ORSV). Clones of the gene RdRp from three Laelia plants (GenBank access numbers HQ393958, HQ393959, HQ393960, HQ393961 and HQ393962), of the CP gene of CymMV from two Oncydium plants (GenBank access numbers HQ393956 and HQ393957), and from three Encyclia plants (GenBank access numbers HQ393953, HQ393954 and HQ393955), were obtained and sequenced. The nucleotide sequences of the capsid protein gene (CP) plantas de Laelia (números de acceso Genbank HQ393958, HQ393959, HQ393960, HQ393961 y HQ393962), del gen CP de CymMV de dos plantas de Oncydium (números de acceso Genbank HQ393956 y HQ393957) y del gen CP de ORSV de tres plantas de Encyclia (números de acceso Genbank HQ393953, HQ393954 y HQ393955), fueron obtenidos y secuenciados. Las secuencias nucleotídicas del gen de la proteína de la cápside (CP) del CymMV y del CP del ORSV, obtenidos de las muestras de orquídeas que se cultivan en México, mostraron similitud de 96 a 97% con CymMV y de 99 a 100% con ORSV, con secuencias disponibles en el Genbank, lo cual confirmó que los aislados de ambos virus de México son idénticos a los de otras partes del mundo.
Filiaciones:
López-Hernández M.S.:
Laboratorio de Microbiología. UBIPRO. FES-Iztacala, Universidad Nacional Autónoma de México, Avenida de los Barrios Número 1. Los Reyes Iztacala, 54090. Tlalnepantla, Estado de México, Mexico
Palacios-Popo P.E.:
Laboratorio de Microbiología. UBIPRO. FES-Iztacala, Universidad Nacional Autónoma de México, Avenida de los Barrios Número 1. Los Reyes Iztacala, 54090. Tlalnepantla, Estado de México, Mexico
de la Torre-Almaraz R.:
Laboratorio de Microbiología. UBIPRO. FES-Iztacala, Universidad Nacional Autónoma de México, Avenida de los Barrios Número 1. Los Reyes Iztacala, 54090. Tlalnepantla, Estado de México, Mexico
|