LAMP-based detection of fire blight We used the E. amylovora specific primers from Shin et al. 2018 to perform the LAMP reactions. The LAMP reaction was optimized for the BioRanger device by using bacterial ooze and young twigs. Direct use of bacterial suspension for LAMP required a pre-lysis at 95 °C for 5 min in the BioRanger device. The amplification pattems of LAMP reactions were highly dependent on the bacterial concentration in the solution (Fig. 3). For instance, LAMP assays showed amplification around x 10' cfu/ml from the bacterial suspension templates (Fig. 3), but the relative fluorescence curves were irregular below x 10³ cfu/ml concentration. The efficiency of the LAMP assay was further improved by using the bacterial DNA as a template, since we were able to detect the minimum 10 cfu/ml serial dilution of DNA from E2002A strain. However, the latter approach will require isolation or re growing of isolated bacteria from the infected samples and DNA extraction from them. Use of ooze and bark rubs from E. amylovora-infected plants also showed E. amylovora detection, as indicated by the fluorescence curves from BioRanger (Fig. 4). We further noted that if samples from bacterial ooze were discolored, or direct use of asymptomatic stem and leaves, did not cause a reaction. In contrast, rubbing the infected bark to obtain bacterial suspensions provided successful amplification of E. amylovora DNA and fire blight diag nosis (Fig. 4).