OCCURRENCE OF TOBRFV IN TOMATO (Solanum lycopersicum L.) GREENHOUSES IN OAXACA, MEXICO

Abstract

Background. Tomato brown rugose fruit virus (ToBRFV) is an emerging pathogen distributed in different regions of Mexico. Objective. To test the presence of ToBRFV in tomato plants of the Mesías variety (HM-Clause) in five greenhouses located in San Pablo Guilá, Oaxaca. Methodology. Using ImmunoStrip (Agdia, Elkhart, USA) a serological assay was performed on the five samples collected from the greenhouse. Using a modified version of Koch's postulates, tomato plants var.192-536 F1 were mechanically inoculated. A biological indexing assay was also performed, where 30-day-old plants of Chenopodium amaranticolor and Nicotiana longiflora were inoculated from infective sap prepared from each sample collected. The sandwich ELISA (DAS-ELISA) was performed 30 days post inoculation (dpi). Subsequently, a fragment of the 475 bp region was amplified by reverse transcription (RT) and polymerase chain reaction (PCR). Results. The ImmunoStrip assay was positive for ToBRFV, inoculation of plants 30 dpi, expressed symptoms of blistering, yellowing, mosaic and leaf deformation. N. longiflora plants showed local necrotic lesions, while Ch. amaranticolor expressed the formation of local chlorotic lesions. Likewise, the samples run by DAS-ELISA yielded a positive diagnosis for ToBRFV. The RT-PCR products obtained amplified a 475 bp fragment confirming the presence of ToBRFV in the five samples studied. Implications. There are limited reports confirming the presence of ToBRFV in Mexican states. Conclusions. To our knowledge, this is the first occurrence of ToBRFV infecting tomato plants in greenhouses in Oaxaca, Mexico.

Keywords

• ensayo serológico
• indexación biológica
• ocurrencia
• tobamovirus.