Establishment of a Loop-mediated Isothermal Amplification Method for Rice Bacterial Leaf Brown Spot Disease

Rice bacterial leaf brown spot disease caused by Pseudomonas syringae pv. syringae（Pss） is a major disease on rice. In recent years, Pss has emerged worldwide, seriously affecting rice production. It is very important to establish a rapid detection method of Pss for the diagnosis and prevention of this disease. In order to robust and accurately diagnose the rice bacterial leaf brown spot disease in the field and laboratory, an assay system for the Pss was developed in this study, and the specific sequence of hrc N was used as the target, based on loop-mediated isothermal amplification（LAMP）. The best detection system was MgSO₄ 8 mmol·L^-1, Bst DNA polymerase 8 U, d NTP 1.4 mmol·L^-1, the ratio of internal and outer primers was 2:1, the reaction temperature was 63℃, the reaction time was 45 min, and the lowest sensitivity was 10~4 CFU·m L^-1. This results provided an accurate and robust method for laboratory and field diagnosis of bacterial leaf brown spot disease of rice.