Visual detection of Potato Virus X in IC-RT-LAMP assay by using HNB dye

Potato can be contaminated by many different viruses that can reduce yield . Potato virus X (PVX) is one of the most economically important viruses of this product. There are several techniques to detect PVX including serological and molecular assays but these methods are time consuming and requiring using complicated tools. The aim of this study was to reduce the time required to detect PVX, using IC-RT-LAMP technique. Fifty leaf samples with symptoms similar to PVX were collected from Kurdestan province and were subjected to a serological (DAS-ELISA) test. One-step IC-RT-LAMP reaction was carried out under isothermal conditions (without RNA extraction) and results were evaluated by agarose gel electrophoresis and hydroxynaphthol blue (HNB) dye. A positive result using the HNB dye was a color change in master-mix from the violet to sky blue. The advantages of IC-RT-LAMP method in compare to other methods are the high specificity, high sensitivity, high rapidity, high efficiency, safety, high efficiency, no expensive tools for amplification, no RNA extraction, no post-amplification treatment of the amplicons, visual detection and user friendly.