Molecular and morphological characterisation of a new root-lesion nematode, Pratylenchus horti n. sp. (Tylenchomorpha: Pratylenchidae), from Ghent University Botanical Garden

Abstract

Summary Root-lesion nematodes, Pratylenchus spp., are one of the most important nematode groups in economic terms. The combination of morphological analyses and molecular analyses based on D2-D3 of 28S rDNA, ITS rDNA, and COI mtDNA regions supported the establishment of a new Pratylenchus species, making a total of 103 valid Pratylenchus species. The females of P. horti n. sp. are characterised by the following traits: low labial region with two annuli continuous to the body, en face form belonging to group II sensu Corbett & Clark (1983) with submedian triangular-shaped segments fused with the oral disc and separated from the lateral segments, lateral field with four incisures at vulval level and lacking areolation, robust stylet 15-17 μm long with rounded knobs, and subcylindrical tail with smooth tail tip. The males are largely similar to the females but differ from the females by the partially areolated lateral field, slightly ventrally arcuate and weakly cephalated spicules (15-19 μm), and ventrally curved elongate conical tail with a poorly protruding, crenate bursa. The new species was recovered from soil and root samples from the rhizosphere of Hedychium greenii growing in the Botanical Garden, Ghent University, Belgium.