Rapid on-site differentiation of two invasive whitefly cryptic species using LAMP

Loop-mediated isothermal amplification (LAMP) is a promising technique for detecting pest species used on the spot due to its simplicity and rapidity. The whitefly is regarded as a species complex encompassing over 44 cryptic species. These species are morphologically indistinguishable but exhibit notable differences in their biological traits. Among them, Bemisia tabaci MEAM1 and MED are the most invasive and devastating members. Accurately and quickly distinguishing between these two invasive whiteflies in the field directly affects the implementation of control measures. However, it is often difficult to directly distinguish between the two when they occur together in the field and require extensive specialist knowledge or instrumentation. However, one of the limitations of the current LAMP is that the reaction mixture requires cold chain, which is not ideal for the detection on the spot. To promote its actual application of LAMP on the spot, the LAMP methods to differentiate B. tabaci MEAM1 and MED were developed in the laboratory, and Trialeurodes vaporariorum was used as a negative control. Then the effect of the preservation condition (room temperature and low temperature) of the reaction mixture on the efficiency of LAMP was compared. The study showed that the application of B. tabaci MED- and MEAM1- LAMP reaction mixture can differentiate B. tabaci MEAM1, B. tabaci MED, and T. vaporariorum after low-temperature preservation for more than 24 h. Finally, we validated the method with temperature-controlled hot-water cup in the field and proved its effectiveness when applied to the field. The results demonstrated that the low-temperature preservation of reaction mixture provides available technical support for the application of LAMP on the spot.