Detection of Tomato Yellow Ring Orthotospovirus in North Khorasan Province, Iran

Özet

Tomato is one of the most important vegetables in the world, cultivated both in the field and in greenhouses. Orthotospoviruses, are among the most economically important pathogens of tomato and cause significant damage to this crop worldwide. Tomato spotted wilt orthotospovirus (TSWV) and Tomato yellow ring orthotospovirus (TYRV) are two species of orthotospoviruses that have been described as potential threats to tomatoes worldwide. In a study of tomato infection in greenhouses in North Khorasan province (Bojnord) with Tomato yellow ring orthotospovirus, plants with symptoms of yellowing and necrosis of leaves and necrosis of stems were observed. Infection of these samples with TYRV was confirmed using test plants, DAS-ELISA, and reverse transcription (RT)-PCR. Infection of Petunia hybrida and Chenopodium quinoa with this virus was localized, while Nicotiana benthamiana, N. glutinosa, Datura stramonium, and Moneymaker tomato had systemic infection. Using DAS-ELISA and a specific antibody (prepared against the nucleocapsid protein) to detect TYRV, Iris yellow spot orthotospovirus, TSWV, Impatiens necrotic spot orthotospovirus, Groundnut bud necrosis orthotospovirus, Groundnut ring spot orthotospovirus, Tomato chlorotic spot orthotospovirus, and Chrysanthemum stem necrosis orthotospovirus, N. benthamiana plants with systemic infection were examined and confirmed to be infected with TYRV only. In the study of samples using RT-PCR, TYRV-specific primers and total RNA extracted from infected N. benthamiana leaves, a fragment of approximately 825 bp in size, which included the nucleocapsid protein gene, was amplified. This fragment was sequenced (HQ154131) and a study of amino acid sequence similarity in GenBank showed that the amino acid sequence of this fragment is 99% similar to the amino acid sequence of TYRV from Fars (ABH07703), Tehran (AAV98587), and Markazi (ACT09488) provinces in Iran. This is the first report of TYRV from North Khorasan province (Bojnord) in Iran.