Bursaphelenchus

About: Bursaphelenchus is a research topic. Over the lifetime, 391 publications have been published within this topic receiving 8155 citations.

First report of Bursaphelenchus xylophilus in Portugal and in Europe

Abstract: A survey of aphelenchid nematodes (Nematoda: Aphelenchida) associated with maritime pine, Pinus pinaster, was conducted in Portugal in 1996 and 1999. A Bursaphelenchus species has been identified for the first time in the Iberian Peninsula. B. xylophilus is reported for the first time in Europe. It was found in very high numbers - up to 38 000 per 10 g of pine wood - inside a few declining trees infested with curculionid, cerambycid and scolytid beetles. Morphological observations, including shape of spicules, bursa, vulva, female tail end and stylet as well as morphometrics, were in accordance with the species description. Species-specific DNA fragment patterns were obtained using ITS-RFLP analysis, with five different restriction enzymes. The importance and implications of this finding are discussed. Premiere signalisation de Bursaphelenchus xylophilus au Portugal, at en Europe - Une enquete sur les nematodes Aphelenchides (Nematoda: Aphelenchida) associes au pin maritime (Pinus pinaster) a ete realisee au Portugal de 1996 a 1999. Une espece de Bursaphelenchus a ete identifiee pour la premiere fois dans la Peninsule Iberique. B. xylophilus est signale pour la premiere fois en Europe. Il a ete trouve en tres grand nombre - jusqu'a 38 000 individus pour 10 g de bois de pin - dans des arbres deperissants infestes par des Coleopteres Curculionides, Cerambycides et Scolytides. Les observations concernant la morphologie - en particulier la forme des spicules, la bourse, la vulve, l'extremite de la queue de la femelle et le stylet - de meme que les donnees morphometriques correspondent a la description de l'espece. Des sequences de fragments d'ADN specifique de l'espece ont ete obtenus par analyse ITS-RFLP a l'aide de cinq enzymes de restriction. L'importance et les implications de cette decouverte sont discutees.

Genomic insights into the origin of parasitism in the emerging plant pathogen Bursaphelenchus xylophilus.

Abstract: Bursaphelenchus xylophilus is the nematode responsible for a devastating epidemic of pine wilt disease in Asia and Europe, and represents a recent, independent origin of plant parasitism in nematodes, ecologically and taxonomically distinct from other nematodes for which genomic data is available. As well as being an important pathogen, the B. xylophilus genome thus provides a unique opportunity to study the evolution and mechanism of plant parasitism. Here, we present a high-quality draft genome sequence from an inbred line of B. xylophilus, and use this to investigate the biological basis of its complex ecology which combines fungal feeding, plant parasitic and insect-associated stages. We focus particularly on putative parasitism genes as well as those linked to other key biological processes and demonstrate that B. xylophilus is well endowed with RNA interference effectors, peptidergic neurotransmitters (including the first description of ins genes in a parasite) stress response and developmental genes and has a contracted set of chemosensory receptors. B. xylophilus has the largest number of digestive proteases known for any nematode and displays expanded families of lysosome pathway genes, ABC transporters and cytochrome P450 pathway genes. This expansion in digestive and detoxification proteins may reflect the unusual diversity in foods it exploits and environments it encounters during its life cycle. In addition, B. xylophilus possesses a unique complement of plant cell wall modifying proteins acquired by horizontal gene transfer, underscoring the impact of this process on the evolution of plant parasitism by nematodes. Together with the lack of proteins homologous to effectors from other plant parasitic nematodes, this confirms the distinctive molecular basis of plant parasitism in the Bursaphelenchus lineage. The genome sequence of B. xylophilus adds to the diversity of genomic data for nematodes, and will be an important resource in understanding the biology of this unusual parasite.

Transmission of Bursaphelenchus Lignicolus (Nematoda: Aphelenchoididae) By Monochamus Alternatus (Coleoptera: Cerambycidae)

Abstract: A total of 21 beetle species, all of which were associated with deteriorated pine trees, were examined for the presence of Bursaphelenchus lignicolus. Dauerlarvae of this nematode were recovered from adults of four species of the Cerambycidae; Monochamus alternatus, Acanthocinus griseus, Arhopalus rusticus, and Corymbia succedanea. Between 75%-100% of the field population of M. alternatus in the diseased pine forests was contaminated, carrying an average number of 15,000 living nematodes per insect. Dauerlarvae were transmitted to pine tissues via feeding site of the insect on living branches. It appears that M. alternatus plays an important role in the spread of the nematode and on associated wilt disease in pine forests.

Aphelenchida, Longidoridae and Trichodoridae: their systematics and bionomics.

Abstract: The Aphelenchida, Longidoridae and Trichodoridae are groups of nematodes that include almost 1000 species from some 40 genera. A number are of known agricultural importance, both in their own right as parasites of fungi or higher plants and/or as vectors of certain plant viruses. This book aims to provide a practical, working guide to the taxa of the Aphelenchida, Longidoridae and Trichodoridae, in such a form as to facilitate usage by both specialist taxonomists and general nematologists.