Résumé
The role of insects as plant virus vectors is well established and extensively studied, both in the field and in the laboratory, to enhance our understanding of plant virus transmission. In contrast, the role of parasitic plants such as dodder (Cuscuta spp.) as plant virus vectors in natural environments remains largely unexplored even though numerous studies have shown that several plant viruses can be transmitted from an infected to a healthy plant through a bridging dodder. This potential for viral transmission by parasitic plants could provide valuable insights for viral epidemiology studies. In this study, we focused on dodder, an annual epiphytic plant characterized by fine, thread-like stems that wrap around host plants to parasitize them. Our overall objective was to analyze the viral communities present in dodder stems and compare them to those of nearby parasitized and non- parasitized plants. We collected in a grazed meadow adjacent to the Tour du Valat in Camargue samples of dodder and three surrounding species, both parasitized and non-parasitized, including Lotus tenuis (Fabaceae), Convolvulus arvensis(Convolvulaceae), and Festuca arundinacea (Poaceae). All samples were individually processed using the virion associated nucleic acid (VANA)-based metagenomics approach. The preliminary results indicate that plant viruses belonging to several plant virus families (e.g. Betaflexiviridae, Closteroviridae, Rhabdoviridae, etc.) are shared by dodder plants and neighboring parasitized and non- parasitized plant species.