Abstract: Pythium splendens is one of entry plant quarantine pests in China. This study established a rapid and sensitive method to detect P. splendens by using loop\|mediated isothermal amplification （LAMP）. A set of 6 primers was designed specifically to recognize the ITS region gene of P. splendens. The LAMP reaction mix was optimized. Reaction temperature and time of the LAMP assay were also optimized at 63℃ for 60 min. Specificity test results showed that these primers were specific for detection of P. splendens. Sensitivity test results showed that the detection limit of this LAMP assay was 0。12 ng·μL-1， which was 100 times higher than conventional PCR. The results of the LAMP reactions were visualized by adding SYBR Green Ⅰ to the reaction tube that can simply be judged by the naked eye. This LAMP-based assay is rapid， sensitive and specific detection of P. splendens， and the only equipment needed for the amplification reaction is a regular laboratory water bath. Thus， we concluded that the LAMP assay can potentially be used for rapid diagnosis in field conditions.

Key words: loop-mediated isothermal amplification （LAMP）, Pythium splendens, plant quarantine pest