Morphometric and Molecular Diversity among Seven European Isolates of Pratylenchus penetrans

Abstract

Pratylenchus penetrans is an economically important root-lesion nematode species that affects agronomic and ornamental plants. Understanding its diversity is of paramount importance to develop effective control and management strategies. This study aimed to characterize the morphological and genetic diversity among seven European isolates. An isolate from the USA was included in the molecular analyses for comparative purposes. Morphometrics of the European P. penetrans isolates generally were within the range of the original descriptions for this species. However, multiple morphometric characteristics, including body length, maximum body width, tail length and length of the post-vulval uterine sac showed discrepancies when compared to other populations. Nucleotide sequence-based analyses revealed a high level of intraspecific diversity among the isolates. We observed no correlation between D2-D3 rDNA- and COXI-based phylogenetic similarities and geographic origin. Our phylogenetic analyses including selected GenBank sequences also suggest that the controversy surrounding the distinction between P. penetrans and P. fallax remains.

Molecular identification of root-lesion nematodes, Pratylenchus spp. in agricultural crops from Costa Rica

“…However, the identification of the genus Pratylenchus is complex due to the number of validated species and the variation within the same species (Nguyen et al, 2019). The morphological identification of Pratylenchus is challenging for diagnostics because of the presence of cryptic species (Bogale et al, 2021) that make some of the species identifiable only by DNA analysis (Singh et al, 2020). Molecular tools for species identification can help to overcome these problems and have become essential for accurate classification (De Luca et al, 2012;Janssen, Karssen, Couvreur, et al, 2017;Janssen, Karssen, Orlando, et al, 2017;Palomares-Rius et al, 2014).…”

First report of Pratylenchus penetrans (Nematoda: Pratylenchidae) associated with artichokes in Vietnam

“…However, to the best of our knowledge, the identification of P. penetrans in Vietnam has never been confirmed by molecular data and has not been associated with artichokes until now. The identification of Pratylenchus species using morphological characters alone can be problematic due to their high interspecific similarity and intraspecific variability ( Bogale et al , 2021 ; Janssen et al , 2017a ; Janssen et al , 2017b ). Therefore, it is recommended to employ both molecular analysis and morphological observation to ensure more accurate identification of Pratylenchus species ( Janssen et al , 2017a ).…”

“…Root-lesion nematodes, particularly those in the genus Pratylenchus, are among the most economically significant plant-parasitic nematodes and can cause substantial damage to a variety of host plants (Castillo & Vovlas, 2007;Geraert, 2013;Sikora et al, 2018). Currently, more than 103 species of the genus Pratylenchus have been described, each with its own host range and specific characteristics (Geraert, 2013;Nguyen et al, 2019).…”

“…Currently, more than 103 species of the genus Pratylenchus have been described, each with its own host range and specific characteristics (Geraert, 2013;Nguyen et al, 2019). Pratylenchus penetrans (Cobb, 1917;Filipjev & Schuurmans Stekhoven, 1941) is one of the most destructive species and has been reported on every continent except Antarctica (Castillo & Vovlas, 2007). Nearly 400 host plants can be infected by this species (Nyczepir & Becker, 1998).…”

“…Its adverse impact on various crops, e.g. carrots, potatoes, tomatoes, and tobacco, has been extensively studied (Castillo & Vovlas, 2007;Sikora et al, 2018). For example, Miller (1975) reported that a population density of 8-55 P. penetrans/100g of soil at planting reduced tomato plant growth by 20-66% after two months.…”