One-step reverse transcription loop-mediated isothermal amplification for the detection of Maize chlorotic mottle virus in maize

- A one-step RT-LAMP was developed for the diagnosis of MCMV in field-grown maize.
- The RT-LAMP procedure could be completed within 60 min using the primers designed in the CP gene.
- The RT-LAMP assay was about 10-fold more sensitive than RT-PCR in this study.
- The RT-LAMP for detecting MCMV is specific and feasible.

Maize chlorotic mottle virus (MCMV) is spreading in many regions worldwide, causing maize lethal necrosis when co-infected with a potyvirid. In this study, one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed to detect MCMV in maize. A set of four specific primers was designed based on the conserved coat protein gene sequences of MCMV. The RT-LAMP could be completed within 60 min under isothermal condition at 63 °C. The sensitivity test showed that the RT-LAMP was about 10-fold more sensitive than RT-PCR and no cross-reactivity was detected with other viral pathogens infecting maize in China. Moreover, the results of RT-LAMP could be visually inspected by SYBR Green I staining in a closed-tube, facilitating high-throughput application of MCMV detection. This method was further verified by testing field-collected samples. These results suggested that the developed MCMV RT-LAMP technique is a rapid, efficient and sensitive method which could be used as a routine screen for MCMV infection.