Sensitive Detection of Beet Yellows Virus, Beet Chlorosis Virus and Beet Mosaic Virus in Plants and in the Aphid Vector Myzus persicae Using RT ‐

ABSTRACT

The recent re‐emergence of sugar beet leaf yellowing disease, driven by aphid‐transmitted viruses following the ban of neonicotinoid insecticides, has created an urgent need for rapid, sensitive and field‐deployable diagnostic tools to support surveillance and management strategies. In this context, we developed and evaluated a reverse transcription loop‐mediated isothermal amplification (RT‐LAMP) assay for the detection of four viruses affecting sugar beet: beet yellows virus (BYV), beet chlorosis virus (BChV), beet mild yellowing virus (BMYV) and beet mosaic virus (BtMV). The assay was designed for direct application to crude extracts from both sugar beet leaves and aphids, without the need for RNA extraction. RT‐LAMP enabled efficient and sensitive detection of BChV, BYV and BtMV in plant samples, with performance comparable to one‐step RT‐PCR. In aphid extracts, RT‐LAMP showed higher sensitivity than RT‐PCR for the detection of these three viruses, highlighting its suitability for vector‐based surveillance approaches. However, BMYV could not be reliably detected under the conditions tested. Despite this limitation, the proposed RT‐LAMP assay provides a rapid, cost‐effective and user‐friendly tool that can be implemented in routine diagnostics and large‐scale monitoring programmes. Its ability to operate on crude samples and to detect viruses in aphid vectors makes it particularly well suited for field surveillance and for evaluating alternative control strategies in the current context of reduced insecticide use.