Rapid and highly specific LAMP assay for detection of Meloidogyne exigua

Abstract Root-knot nematodes (RKN - Meloidogyne spp.) are sedentary endoparasites that attack a wide range of plants species, including coffee. Meloidogyne exigua , M. incognita , and M. paranaensis are most common RKN species found in coffee-producing areas of Brazil, with M. exigua being the most prevalent. Effective control of these nematodes may be species-specific, necessitating accurate identification. Loop-mediated isothermal amplification (LAMP) offers a rapid, accurate, and cost-effective alternative for molecular identification of plant-parasitic nematodes. In this study, we developed a novel LAMP assay for detecting M. exigua by targeting the 28 S rDNA gene. The reaction was monitored through a colorimetric change using a commercial master mix with a pH indicator and confirmed by agarose gel electrophoresis. The assay specifically detected M. exigua within 75 min without cross-amplifying DNA from the other coffee root-knot nematodes, M. incognita and M. paranaensis . Additionally, the LAMP assay exhibited high sensitivity, successfully detecting 2.6 fg µL − 1 of M. exigua DNA. This method can be a highly effective tool for accurately identifying M. exigua , aiding in the diagnosis and management of this nematode.