First Detection of Tomato Torrado Virus (ToTV) in Greenhouse Tomato Using RT-PCR and Sequencing Methods

Abstract

Severe chlorotic spotting, leaf necrosis, wilting, and fruit deformation symptoms resembling torrado disease were observed in greenhouse-grown tomato plants cultivated under intensive production conditions. Symptomatic samples collected from commercial tomato greenhouses were analyzed to determine the presence and molecular identity of Tomato torrado virus (ToTV) using reverse transcription polymerase chain reaction (RT-PCR) and nucleotide sequencing approaches. Total RNA extracted from infected leaf tissues was subjected to RT-PCR using virus-specific primers targeting conserved genomic regions associated with ToTV detection. Amplification of the expected DNA fragments confirmed the presence of the virus in symptomatic plants, whereas healthy control samples showed no amplification. Sequence analysis of the amplified products demonstrated high nucleotide similarity with previously reported ToTV isolates available in international sequence databases. Phylogenetic analysis grouped the obtained isolates within established ToTV lineages, confirming their close evolutionary relationship with isolates reported from other tomato-growing regions. Disease incidence was markedly higher in greenhouses with elevated whitefly populations and dense plant canopies, conditions favorable for vector activity and virus dissemination. Infected tomato plants exhibited severe reduction in vigor, impaired fruit development, and decline in marketable yield and quality. The occurrence of ToTV represents a potential emerging threat to greenhouse tomato production due to its rapid spread and destructive impact on crop performance. Accurate molecular detection through RT-PCR and sequencing provides reliable tools for early diagnosis, epidemiological surveillance, and implementation of timely management strategies. The present investigation constitutes the first detection of ToTV in greenhouse tomato production within the studied region and expands current knowledge regarding the distribution and molecular characterization of this economically important viral pathogen.