Purification/Amplification-Free RNA Detection Platform for Rapid and Multiplex Diagnosis of Plant Viral Infections

Genetic tests are highly sensitive, and quantitativemethods fordiagnosing human viral infections, including COVID-19, are also beingused to diagnose plant diseases in various agricultural settings.Conventional genetic tests for plant viruses are mostly based on methodsthat require purification and amplification of viral genomes fromplant samples, which generally take several hours in total, makingit difficult to use them in rapid detection at point-of-care testing(POCT). In this study, we developed Direct-SATORI, a rapid and robustgenetic test that eliminates the purification and amplification processesof viral genomes by extending the recently developed amplification-freedigital RNA detection platform called SATORI, allowing the detectionof various plant viral genes in a total of less than 15 min with alimit of detection (LoD) of 98 similar to copies/mu L using tomatoviruses as an example. In addition, the platform can simultaneouslydetect eight plant viruses directly from similar to 1 mg of tomato leaveswith a sensitivity of 96% and a specificity of 99%. Direct-SATORIcan be applied to various infections related to RNA viruses, and itspractical use is highly anticipated as a versatile platform for plantdisease diagnostics in the future.