Survey and Molecular Identification of Tospoviruses Infecting Vegetable Crops in Greenhouse Production Systems

Abstract

Tospoviruses are among the most destructive plant viruses affecting vegetable crops in greenhouse production systems, causing severe yield losses and quality deterioration. The present study aimed to conduct a survey and molecular identification of tospoviruses infecting major vegetable crops grown under protected cultivation. Field surveys were carried out in greenhouse units cultivating tomato, pepper, cucumber, and leafy vegetables, and symptomatic plants exhibiting chlorotic ringspots, necrotic lesions, leaf deformation, and stunted growth were collected. Total RNA was extracted from infected samples and subjected to RT-PCR using primers specific to conserved regions of tospovirus genomic segments. Amplified products were sequenced and analyzed for molecular characterization and phylogenetic relationships. Results confirmed the presence of multiple tospovirus species, with isolates showing high sequence similarity to known strains of economically important tospoviruses. Phylogenetic analysis revealed clustering of isolates into distinct groups, indicating genetic diversity and possible introduction of multiple viral strains into greenhouse systems. Disease incidence was found to be influenced by vector activity, particularly thrips populations, as well as environmental conditions such as temperature and humidity prevailing in protected structures. Mixed infections were also observed in some samples, suggesting complex viral interactions within host plants. The study highlights the rapid spread and genetic variability of tospoviruses in greenhouse vegetable production systems. These findings emphasize the need for continuous monitoring, molecular diagnostics, and strict vector management strategies. Overall, the results provide important insights into the diversity and molecular epidemiology of tospoviruses and support the development of integrated disease management approaches to reduce their impact on protected vegetable cultivation.