Detection of Botrytis cinerea by loop-mediated isothermal amplification

Aims: To develop a sensitive, rapid and simple method for detection of Botrytis cinerea based on loop-mediated isothermal amplification (LAMP) that would be suitable for use outside a conventional laboratory setting. Methods and Results: A LAMP assay was designed based on the intergenic spacer of the B. cinerea nuclear ribosomal DNA (rDNA). The resulting assay was characterized in terms of sensitivity and specificity using DNA extracted from cultures. The assay consistently amplified 65 pg B. cinerea DNA. No cross-reactivity was observed with a range of other fungal pathogens, with the exception of the closely related species Botrytis pelargonii. Use of a novel real-time LAMP platform (the OptiGene Genie I) allowed detection of B. cinerea in infected rose petals, with amplification occurring in < 15 min. Conclusions: The LAMP assay that was developed is suitable for rapid detection of B. cinerea in infected plant material. Significance and Impact of the Study: The LAMP method combines the sensitivity and specificity of nucleic acid-based methods with simplified equipment and a reduced reaction time. These features make the method potentially suitable for on-site use, where the results of testing could help to inform decisions regarding the storage and processing of commodities affected by B. cinerea, such as cut flowers, fruit and vegetables.