TY - JOUR T1 - The pitfalls of molecular species identification: a case study within the genus Pratylenchus (Nematoda: Pratylenchidae) JF - Nematology Y1 - 2017 DO - 10.1163/15685411-00003117 A1 - Janssen, Toon A1 - Karssen, Gerrit A1 - Couvreur, Marjolein A1 - Waeyenberge, Lieven A1 - Bert, Wim SP - 1–21 KW - acrobeloides cf KW - barcoding provide a KW - DIAGNOSTICS KW - for KW - identification of organisms and KW - mislabelled sequences KW - MOLECULAR PHYLOGENY KW - molecular taxonomy and dna KW - nanus KW - new synonym KW - powerful tool for the KW - pratylenchus flakkensis KW - pratylenchus goodeyi KW - pratylenchus lentis n KW - pratylenchus pratensis KW - syn KW - topotypes VL - 00 SN - 1568541100003 UR - http://booksandjournals.brillonline.com/content/journals/10.1163/15685411-00003117 ER - TY - BOOK T1 - Morphological and molecular characterisation of Scutellonema species from yam (Dioscorea spp.) and a key to the species of the genus T2 - Nematology Y1 - 2017 DO - 10.1163/15685411-00003084 A1 - Kolombia, Yao A. A1 - Karssen, Gerrit A1 - Viaene, Nicole A1 - Kumar, P. Lava A1 - Joos, Lisa A1 - Coyne, Danny L. A1 - Bert, Wim SP - 751–787 KW - asiedu KW - clathricaudatum KW - coi KW - crop KW - cultivated for its edible KW - d2-d3 KW - DIAGNOSTICS KW - dioscorea spp KW - ghana KW - IDENTIFICATION KW - is an important staple KW - KEY KW - nigeria KW - phylogeny KW - scutellonema KW - scutellonema cavenessi KW - scutellonema paralabiatum KW - species delimitation KW - tubers in west africa KW - west africa KW - yam JF - Nematology VL - 19 SN - 1568541100003 UR - http://booksandjournals.brillonline.com/content/journals/10.1163/15685411-00003084 ER - TY - BOOK T1 - Integrative taxonomy of root-knot nematodes reveals multiple independent origins of mitotic parthenogenesis T2 - PLoS ONE Y1 - 2017 DO - 10.1371/journal.pone.0172190 A1 - Janssen, Toon A1 - Karssen, Gerrit A1 - Topalović, Olivera A1 - Coyne, Danny A1 - Bert, Wim SP - e0172190 AB - During sampling of several Coffea arabica plantations in Tanzania severe root galling, caused by a root-knot nematode was observed. From pure cultures, morphology and mor-phometrics of juveniles and females matched perfectly with Meloidogyne africana, whereas morphology of the males matched identically with those of Meloidogyne decalineata. Based on their Cox1 sequence, however, the recovered juveniles, females and males were con-firmed to belong to the same species, creating a taxonomic conundrum. Adding further to this puzzle, re-examination of M. oteifae type material showed insufficient morphological evi-dence to maintain its status as a separate species. Consequently, M. decalineata and M. otei-fae are synonymized with M. africana, which is herewith redescribed based on results of light and scanning electron microscopy, ribosomal and mitochondrial DNA sequences, isozyme electrophoresis, along with bionomic and cytogenetic features. Multi-gene phylogenetic analy-sis placed M. africana outside of the three major clades, together with M. coffeicola, M. ichino-hei and M. camelliae. This phylogenetic position was confirmed by several morphological features, including cellular structure of the spermatheca, egg mass position, perineal pattern and head shape. Moreover, M. africana was found to be a polyphagous species, demonstrat-ing that " early-branching " Meloidogyne spp. are not as oligophagous as had previously been assumed. Cytogenetic information indicates M. africana (2n = 21) and M. ardenensis (2n = 51–54) to be a triploid mitotic parthenogenetic species, revealing at least four independent ori-gins of mitotic parthenogenesis within the genus Meloidogyne. Furthermore, M. mali (n = 12) was found to reproduce by amphimixis, indicating that amphimictic species with a limited num-ber of chromosomes are widespread in the genus, potentially reflecting the ancestral state of the genus. The wide variation in chromosome numbers and associated changes in reproduc-tion modes indicate that cytogenetic evolution played a crucial role in the speciation of root-knot nematodes and plant-parasitic nematodes in general. JF - PLoS ONE VL - 12 SN - 1111111111 ER - TY - JOUR T1 - An early record of Meloidogyne fallax from Ireland JF - ZooKeys Y1 - 2017 DO - 10.3897/zookeys.643.11266 A1 - Topalović, Olivera A1 - Moore, John F. A1 - Janssen, Toon A1 - Bert, Wim A1 - Karssen, Gerrit SP - 33–52 KW - CHARACTERS KW - Cork KW - Host KW - morphology KW - Morphometrics KW - Root-knot nematode AB - Root-knot nematodes, Meloidogyne spp., cause huge economic losses worldwide. Currently, three Meloidogyne spp. are present on the quarantine A2 list of EPPO, M. chitwoodi, M. fallax and M. enterolobii. As a quarantine organism, M. fallax has been detected in England and Northern Ireland on sport turf in 2011, and in England on leek in 2013. However, its presence in Ireland has probably been overlooked since 1965, when Mr. John F. Moore and Dr. Mary T. Franklin had detected a new Meloidogyne species for that time. While the relevant data was recorded and a preliminary manuscript describing the species was prepared but never submitted for publication, and together with the original slides, pictures and drawings, it was restudied recently. We compared the population of Irish Meloidogyne sp. to other similar Meloidogyne spp. Careful observation and comparison shows that it belongs to M. fallax. The characters found to be common for Irish Meloidogyne sp. and M. fallax are female stylet length (14.6 μm) with oval to rounded basal knobs, oval shaped perineal pattern with moderately high dorsal arch, slender stylet in males (18.5 μm) with set off and rounded basal knobs, slightly set off male head with one post-labial annule and incomplete transverse incisures, and second-stage juveniles with large and rounded stylet basal knobs, and a gradually tapering tail (46.9 μm) with a broadly rounded tip and a clearly delimitated smooth hyaline part sometimes marked by constrictions (12.9 μm). The host test and gall formation also correspond to M. fallax. The identification could not be additionally supported by molecular analysis, as we were unable to extract DNA from the old permanent slides. Nevertheless, our study reveals that the Meloidogyne species detected in Ireland in 1965 belongs to M. fallax. VL - 2017 ER - TY - JOUR T1 - Molecular characterization and species delimiting of plant-parasitic nematodes of the genus Pratylenchus from the penetrans group (Nematoda: Pratylenchidae) JF - Molecular Phylogenetics and Evolution Y1 - 2017 DO - 10.1016/j.ympev.2017.07.027 A1 - Janssen, Toon A1 - Karssen, Gerrit A1 - Orlando, Valeria A1 - Subbotin, Sergei A. A1 - Bert, Wim KW - Cryptic species complex KW - DNA Barcoding KW - phylogeny KW - Pratylenchus arlingtoni KW - Root-lesion nematodes KW - species delimitation AB - Root-lesion nematodes of the genus Pratylenchus are an important pest parasitizing a wide range of vascular plants including several economically important crops. However, morphological diagnosis of the more than 100 species is problematic due to the low number of diagnostic features, high morphological plasticity and incomplete taxonomic descriptions. In order to employ barcoding based diagnostics, a link between morphology and species specific sequences has to be established. In this study, we reconstructed a multi-gene phylogeny of the Penetrans group using nuclear ribosomal and mitochondrial gene sequences. A combination of this phylogenetic framework with molecular species delineation analysis, population genetics, morphometric information and sequences from type location material allowed us to establish the species boundaries within the Penetrans group and as such clarify long-standing controversies about the taxonomic status of P. penetrans, P. fallax and P. convallariae. Our study also reveals a remarkable amount of cryptic biodiversity within the genus Pratylenchus confirming that identification on morphology alone can be inconclusive in this taxonomically confusing genus. UR - http://dx.doi.org/10.1016/j.ympev.2017.07.027 ER - TY - JOUR T1 - mtCOI successfully diagnoses the four main plant-parasitic Aphelenchoides species (Nematoda: Aphelenchoididae) and supports a multiple origin of plant-parasitism in this paraphyletic genus JF - European Journal of Plant Pathology Y1 - 2017 DO - 10.1007/s10658-016-1141-1 A1 - Sanchez-Monge, Alcides A1 - Janssen, Toon A1 - Fang, Yiwu A1 - Couvreur, Marjolein A1 - Karssen, Gerrit A1 - Bert, Wim KW - Concatenated analysis KW - Foliar nematodes KW - Molecular b PB - European Journal of Plant Pathology UR - http://link.springer.com/10.1007/s10658-016-1141-1 ER - TY - JOUR T1 - First Report of Potato Cyst Nematode (Globodera rostochiensis) Infecting Potato (Solanum tuberosum L.) in Rwanda JF - Plant Disease Y1 - 2019 DO - 10.1094/pdis-04-19-0891-pdn A1 - Niragire, Ildephonse A1 - Couvreur, Marjolein A1 - Karssen, Gerrit A1 - Uwumukiza, Beatrice A1 - Bert, Wim SP - 19–21 VL - 409 SN - 1568541100003 ER -