Rapid detection of chilli leaf curl virus using loop-mediated isothermal amplification

Abstract

Chilli leaf curl virus (ChiLCV) is a significant begomovirus that infects chili plants. To detect ChiLCV infection, a loop-mediated isothermal amplification (LAMP) assay was designed to be easy, quick, and efficient. The assay uses a set of five specific primers that target the coat protein gene (av1) of the target virus to detect the presence of the virus. The LAMP reaction amplifies the target gene within 45 min at 63 °C, with an 8mM dNTP concentration. This method showed no cross-reactivity with other tested begomoviruses that confirmed selective ChiLCV amplification. The sensitivity test revealed that LAMP was more sensitive than PCR. The LAMP assay displayed a remarkable detection limit of 10 fg/μL, which is superior than the PCR sensitivity of 10 pg/μL. Field sample validation yielded concordant results with PCR. This study introduces a cost-effective, and highly sensitive method for ChiLCV detection. Validation of LAMP with symptomatic leaves samples produced consistent results with PCR, demonstrating that the LAMP method could detect all infected samples.