Advances in Nanosensor-Based Diagnostics for Plant Viral Pathogens

Plant virus infections continue to pose a serious threat to global food security, causing significant agricultural and economic losses. Conventional diagnostic techniques such as enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction (PCR)and next-generation sequencing (NGS) are highly sensitive and specific but are complex, require trained personnel and involve long processing times. The convergence of nanotechnology and biosensing has revolutionized plant virus diagnostics by enabling rapid, ultrasensitive and portable analytical platforms. This review presents an overview of recent progress in nanosensor-based detection of plant viral pathogens, emphasizing advances in diagnostic platforms, transduction mechanisms, nanomaterial technologies, and their applications in both laboratory and field conditions. Nanosensors employing gold nanoparticles, graphene, carbon nanotubes, quantum dots and metal oxides have demonstrated excellent analytical performance for detecting major plant viruses such as tobacco mosaic virus, cucumber mosaic virus, potato virus Y and tomato yellow leaf curl virus. Depending on their transduction mechanism — electrochemical, optical, piezoelectric, or field-effect transistor (FET)-based — these nanosensors exhibit femto- to attomolar sensitivity, rapid response and seamless integration with paper-based and microfluidic systems. Their application in point-of-care (POC) and field diagnostics enables early detection and real-time monitoring of crop health. Despite these advances, challenges persist regarding reproducibility, sensor stability, environmental interference and large-scale commercialization. Emerging technologies such as crispr–cas-integrated nanosensors, green nanomaterial synthesis, nanocomposite stabilization and AI-driven data analytics are paving the way for robust and scalable platforms. The integration of nanosensor technology with Internet of Things (IoT) paradigms and precision agriculture systems heralds a new generation of intelligent, sustainable and technology-enabled crop protection.