An efficient loop-mediated isothermal amplification procedure (LAMP) for the detection of "Candidatus Liberibacter solanacearum" (Lso), the bacterial causal agent of potato zebra chip (ZC) disease, is described in this chapter. Similar to the polymerase chain reaction (PCR), the LAMP employs a bacterial polymerase to amplify specific DNA sequences. However, the method differs from conventional PCR in that it uses six primers specific to the target region to generate a loop structure and autocycling strand displacement rather than thermocycling for sequence amplification. Moreover, unlike PCR that requires agarose gel electrophoresis for resolution, the positive LAMP results can be visualized directly as a precipitate within the reaction tubes. The 16S rDNA gene of "Ca. Liberibacter solanacearum" was used as the target for the design of the six LAMP primers. The LAMP technique is a reliable, rapid, and cost-effective method of detecting the "Ca. Liberibacter solanacearum" pathogen in the potato/tomato psyllid, Bactericera cockerelli, and in field-grown potato plants and tubers.