Species-specific polymerase chain reaction primers for simple detection of Bursaphelenchus fraudulentus (Nematoda: Parasitaphelenchidae)

Abstract

Nematology , 2010, Vol. 12(1), 157-160 Short communication Species-specific polymerase chain reaction primers for simple detection of Bursaphelenchus fraudulentus (Nematoda: Parasitaphelenchidae) Anna F I L I P I A K 1 , ∗ , Agata J AKUBOW SKA 1 , 2 and Marek T OMALAK 1 Bursaphelenchus fraudulentus Ruhm, 1956 (Nema- toda: Parasitaphelenchidae) is a tree-inhabiting species frequently found in Europe (Ruhm, 1956; Schauer-Blume & Sturhan, 1989; Tomalak, 2004; Carletti et al ., 2005) and Asia (Braasch et al ., 2001). It is primarily found in dy- ing or dead deciduous trees (Ruhm, 1956; Schauer-Blume & Sturhan, 1989), although occasionally reported from conifers (Braasch et al ., 2001). Within the genus the spe- cific morphological characters (i.e. , vulval flap, shape of spicules, position of caudal papillae and presence of four incisures in the lateral fields) place B. fraudulentus into a distinct xylophilus -group which comprises eight other, morphologically similar, species, including the quarantine pest B. xylophilus (Gu et al ., 2008). Reliable methods of taxonomic identification of these species are therefore of particular interest to plant quarantine services. Several molecular techniques have been developed and used for identification of Bursaphelenchus spp. (Wang et al. , 1999; Matsunaga & Togashi, 2004; Burgermeister et al ., 2005; Castagnone et al. , 2005; Leal et al ., 2005, 2007) with ITS-RLFP analysis the most widely used in research and quarantine practice. An alternative method, based on a simple PCR amplification with primers specific for B. xylophilus and B. mucronatus (Matsunaga & Togashi, 2004), enables rapid and precise species identification, even from a single nematode (Filipiak et al ., 2007). Both native European species from the xylophilus - group, i.e. , B. mucronatus and B. fraudulentus , are rela- tively common and harmless to trees. They can be mor- phologically difficult to distinguish from each other and from the quarantine pest B. xylophilus. The provision of PCR primers specific for the DNA of B. fraudulentus , in addition to those already existing for B. xylophilus and B. 1 Department of Biological Pest Control and Quarantine, Institute of Plant Protection, Wladyslawa Wegorka 20, Poznan, 60-318, Poland 2 Department of Genetics, University of Valencia, Dr. Moliner 50, 46-100, Burjassot, Spain ∗ Corresponding author, e-mail: A.Filipiak@ior.poznan.pl Received: 22 October 2008; revised: 26 June 2009 Accepted for publication: 29 June 2009 Keywords: Bursaphelenchus xylophilus -group, diagnostics, molecular. mucronatus (Matsunaga & Togashi, 2004), enhances the utility of this method. The main objectives of our research were to sequence the ITS regions of the B. fraudulentus genome and to design specific primers for PCR amplifica- tion. Eight isolates of B. fraudulentus , two of B. mucrona- tus and one of B. xylophilus were examined. The Aus- trian (Osterreich), Russian (DE10w), German (Helmstedt and H26), and Hungarian (Ungarn) isolates of B. fraudu- lentus and the isolate of B. xylophilus (China) were ob- tained from the nematode collection of the Federal Re- search Centre for Cultivated Plants (formerly Federal Bi- ological Research Centre for Agriculture and Forestry – BBA), Braunschweig, Germany (Dr T. Schroder). All the remaining nematode populations were isolated from in- fested trees in Poland. The populations of B. fraudulentus originated from Poznan (PL-01 and PL-05) and Kornik (PL-04) and those of B. mucronatus from Nowy Tomysl (NTo-01) and Slawa Slaska (SlS-01). Their taxonomic identification was originally based on morphological and morphometric characteristics and subsequently confirmed by ITS-RLFP analysis according to the protocol described by Burgermeister et al. (2005). Prior to examination, all isolates were reared on Botrytis cinerea /malt agar (4.5%) at 25 ◦ C for ca 2 weeks. Propagated nematodes were col- lected by the Baermann funnel method and stored in 10 μ l H 2 O at − 20 ◦ C until use. Extraction of DNA was performed according to the method described by Iwahori et al. (1998), with mi- nor modifications to the composition of the lysis buffer: 100 mM Tris, pH 8.5, 100 mM NaCl, 50 mM EDTA, 1% SDS, 1% β -mercaptoethanol, 100 μ g ml − 1 proteinase K per 100 μ l buffer. Before incubation, the mixture was © Koninklijke Brill NV, Leiden, 2010 DOI:10.1163/138855409X12469543767319 Also available online - www.brill.nl/nemy 157