Related Experiment Video
Updated: Sep 28, 2025
On-Site Molecular Detection of Soil-Borne Phytopathogens Using a Portable Real-Time PCR System
Published on: February 23, 2018
Cas12a-Based Diagnostics for Potato Purple Top Disease Complex Associated with Infection by 'Candidatus Phytoplasma
Matthew S Wheatley1, Qin Wang1, Wei Wei2
1Department of Plant Pathology and Environmental Microbiology, Huck Institute of the Life Sciences, the Pennsylvania State University, University Park, PA 16802.
Abstract:
'Candidatus Phytoplasma trifolii' is a cell wall-less phytopathogenic bacterium that infects many agriculturally important plant species such as alfalfa, clover, eggplant, pepper, potato, and tomato. The phytoplasma is responsible for repeated outbreaks of potato purple top (PPT) and potato witches' broom (PWB) that occurred along the Pacific Coast of the United States since 2002, inflicting significant economic losses. To effectively manage these phytoplasmal diseases, it is important to develop diagnostic tools for specific, sensitive, and rapid detection of the pathogens. Here we report the development of a DNA endonuclease targeted CRISPR trans reporter (DETECTR) assay that couples isothermal amplification and Cas12a transcleavage of fluorescent oligonucleotide reporter for highly sensitive and specific detection of 'Candidatus Phytoplasma trifolii'-related strains responsible for PPT and PWB. The DETECTR assay was capable of specifically detecting the 16S-23S ribosomal DNA intergenic transcribed spacer sequences from PPT- and PWB-diseased samples at the attomolar sensitivity level. Furthermore, the DETECTR strategy allows flexibility to capture assay outputs with fluorescent microplate readers or lateral flow assays for potentially high-throughput and/or field-deployable disease diagnostics.
