Morphological and molecular characterisations of the damaging root-knot nematode, Meloidogyne arenaria (Neal, 1889) Chitwood, 1949, parasitising black pepper and coffee in Vietnam

Abstract

The root-knot nematodes, Meloidogyne spp., are endo-parasitic nematodes that can cause significant damage to numerous economically important crops. In a survey of plant pathogens, we have recorded for the first time the infestation of the destructive pest, Meloidogyne arenaria, on black pepper (Piper nigrum) and coffee (Coffea canephora) in Vietnam, the two most important cash crops in the country. Our study characterises four M. arenaria populations associated with black pepper and coffee using morphology, morphometrics, and molecular data of five gene regions, including ITS, D2-D3 of 28S rRNA, COI, COII-16S, and Nad5 mtDNA regions. The detailed morphological data of these nematode populations are useful for the diagnosis of M. arenaria in general. Additionally, molecular barcodes that are unequivocally linked with morphological and morphometric data can facilitate the molecular identification of this pest. Since M. arenaria is known as one of the most destructive plant pathogens, its presence in black pepper and coffee in Vietnam needs to be monitored carefully.