Development of a LAMP‐Based Molecular Species Diagnostic Tool for the Invasive Pest, <i>Tuta absoluta</i> and <i>Phthorimaea operculella</i> (Lepidoptera, Gelechiidae)

ABSTRACT The tomato leaf miner, Tuta absoluta , is a destructive and rapidly spreading invasive pest that poses a major threat to tomato production worldwide. Native to South America, this species has expanded into Africa, Europe, Asia, and, more recently, has been detected in Korea. Management of T. absoluta is particularly challenging due to its high reproductive potential, resistance to commonly used insecticides, and morphological similarity to sympatric gelechiid pests such as Phthorimaea operculella , which complicate accurate identification. In this study, we developed a loop‐mediated isothermal amplification (LAMP) assay for the rapid and specific detection of T. absoluta , utilising diagnostic markers from the mitochondrial genome. The assay was optimised to function effectively at 61°C and employs a set of species‐specific primers that enable amplification within 20 min. It demonstrated high sensitivity, reliably detecting as little as 100 femtograms of genomic DNA. To support field applicability, we established a rapid and simplified tissue‐based DNA extraction method that requires minimal laboratory infrastructure. Specificity and reliability were validated using samples collected from multiple geographic locations, ensuring robustness across populations. The combination of speed, sensitivity, and ease of use makes this assay highly suitable for field surveillance, quarantine inspection, and early detection efforts. This molecular diagnostic tool offers a cost‐effective and practical approach for the identification of T. absoluta , contributing significantly to integrated pest management programmes and the mitigation of economic losses in tomato‐producing regions worldwide.