Symposium Abstracts
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Nematology,2002,V ol.4(2), 123-314 Symposium abstracts 001 Bursaphelenchusxylophilus and B.mucronatus untilthe recent identi cation in Portugal. It is felt that if inJapan: where arethey from? introducedthe nematode would establish populations or interbreedwith endemic non-virulent species. This ban 1; 2 Hideaki IWAHORI ¤, Natsumi KANZAKI and hashadmajorconsequences on theNorth American forest 2 Kazuyoshi FUTAI industry.Recently many new species of Bursaphelenchus 1NationalAgricultural Research Center for Kyushu Okinawa havebeen described from deador dyingpines throughout Region,Nishigoushi, Kumamoto 861-1192, Japan Europe.Because morphological characters are limited 2 KyotoUniversity, Kyoto 606-8502, Japan inusefulness for speciesdescriptions and cannot be ¤[email protected] usedto differentiate populations, molecular taxonomy hasbecome important. W ewilllook at the accuracy Geographicaldistribution and speciation of Bursaphelen- ofmethods used for speciesidenti cation and at what chusxylophilus (pinewoodnematode) and B. mucrona- criteriamight be used to de ne and differentiate species tus were inferredfrom molecularphylogenetic analysis of Bursaphelenchus whenconsidering import and export andchromosomal number .Severalisolates of B. xylop- bans. hilus and B.mucronatus inJapan and from someother countrieswere usedfor DNA sequencingof the ITS re- 003Mitigating the pinewoodnematode and its gionsin ribosomalDNA. Publishedresearch on thenum- vectorsin transported coniferous wood berof chromosomesof selectedisolates was usedto iden- tifya relationshipin speciation of these nematodes. W e David DWINELL identied three (or four) groupsof B.xylophilus and two B.mucronatus groups of basedon molecularphylogenetic USDA ForestService, 320 Green St., Athens, GA 30602,USA information.These groups corresponded to differences in [email protected] chromosomalnumber .Wehypothesiseda routeof geo- graphicalmigration and speciation of these two nema- Thepinewood nematode ( Bursaphelenchusxylophilus ) todesby estimatingthe chronology of speciation.The re- (PWN) hasbeen intercepted in pine chips, unseasoned sultssupport a previoushypothesis that B.xylophilus and lumberand packing-case wood. Likewise, PWN insect B.mucronatus divergedwith the separation of theEuro- vectors, Monochamus spp.,have been found in pallets, peanand North American continents. In conclusion, our crates,and dunnage. As aresultof these interceptions resultscon rmed that Japanese B.xylophilus was intro- andthe known consequences of the introduction of the ducedrecently to Japan ( ca 100years ago) from North PWN, manycountries regulate the import of coniferous America,and suggested that both Japanese B.xylophilus wood.Science-based procedures are needed to ensurethat B.mucronatus and mighthave two origins in NorthAmer- globallytransported wood is free ofthe PWN andits icaand Eurasia, respectively. vectors.Mitigation measures that have been investigated includeprevention, host selection, and treatment by 002Molecular taxonomy as amethodfor describing fumigation,irradiation, chemical dips, pressure treatment populationsand species within the pinewood withpreservatives, and elevated temperature. A mill nematodespecies complex certication program for lumber(no bark, no grubholes) isrational, but has not got much support. Air-drying Robert I. BOLLA woodto its equilibrium moisture content will eliminate Departmentof Biology,Saint Louis University, 3507 Laclede, thePWN. Switchingto hardwood lumber for wood St.Louis, MO 63103-2010,USA packingmaterial is a short-termsolution. Irradiation [email protected] anddipping wood in borates have shown little promise. Theef cacy of pressure-treatinggreen pine lumber with Shipmentof untreatedpinewood from NorthAmerica and chromatedcopper arsenate has been shown. Pine chips severalAsian countries into Europe has beenbanned. This canbe fumigatedwith phosphine. Logs, lumber, and wood banhas arisen because of the potential for introduction packingmaterial can be fumigatedwith methyl bromide. ofspecies of Bursaphelenchus pathogenicto pine into Heatingconiferous wood to a coretemperature of 60 ±C Europewith the consequent effect comparable to thatseen willeradicate the PWN andits vectors. inJapan, China and Korea. This ban is basedon thelack ofidentication of Bursaphelenchusxylophilus in Europe © KoninklijkeBrill NV ,Leiden,2002 123 Epidemiologyof PineWilt disease (1-7) and Plenary Session (8) 004Occurrence of the pinewoodnematode, iscaused by the pinewood nematode, Bursaphelenchus Bursaphelenchusxylophilus inPortugal and xylophilus,withthe pine sawyer, Monochamusalternatus , perspectivesof the diseasespread in Europe asvector .Wepresenta mathematicalmodel to describe thehost-parasite interaction between pines and pine Manuel MOTA sawyers carryingnematodes on thebasis of detaileddata NemaLab,ICAM, Dept.de Biologia,Universidade de Évora, takenfrom theincidence of pine wilt disease at a study 7000É vora,P ortugal sitelocated on the northwest coast of Japan. With this [email protected] modelwe simulatethe temporal change in the incidence ofthe disease and predict how the epidemic could be In1999, the pinewood nematode (PWN), Bursaphelen- controlledby eradicationof thepine sawyer. Furthermore, chusxylophilus, was foundand identi ed for the rst themodelis extended to studythe spatialspread of disease timein Portugaland in Europe. Following detection, Por- ona largescale, by incorporating short-range dispersal tugueseauthorities initiated the implementation of erad- ofthe pine sawyer, together with long-range dispersal icationmeasures during 1999 and 2000, following an throughair convection or transportation of logs infested alertprovided to European Community of cials; as a re- withnematodes. W eestimatethat more than 10% of sult,the nematode was conrmed to be con ned in the sawyers undergolong-distance dispersal in areas where Setúbal region, near Lisbon.A taskforce from thefollow- rapidspread of thedisease is observed. upgroup (GANP) createdby the Secretary of State for theRural Development established a nationaleradication programme(PROLUNP) to i)containPWN withinthe 006Fluctuation in genetic structure andvirulence initialgeographic limits; ii)implementeradication mea- ofpinewoodnematode in host pinetrees and insect sures; and iii)monitorPWN atanationallevel. Research vectorsat the end ofapinewilt epidemic ispresently being conducted both at universities as well Katsumi TOGASHI1; , Sachie ENOKI 1, Yuji ISAGI 1 and asresearch institutes, focusing on thecharacterisation of ¤ Takuya AIKAWA 2 Bursaphelenchus speciesassociated with maritime pine, aswell as ontheinsect vector, Monochamusgalloprovin- 1 Facultyof IntegratedArts and Sciences, Hiroshima University, cialis.Recentreports indicate that the nematode may be Kagamiyama1-7-1, Higashi-Hiroshima 739-8521, Japan 2 presentin Siberia (Russia), which would present a threat Forestryand F orestProducts Research Institute, Kukisaki, toEastern European forestry. Efforts arepresently being Ibaraki305-8687, Japan [email protected] developedby severalEuropean countries to establisha re- ¤ searchconsortium to detect and study the possible pres- Thepinewood nematode, the causative agent of pinewilt enceof PWN, for anewPRA. Arecentworkshop held disease,is harboured as a subpopulationin each dead inPortugal in 2001 was anopportunity for sharingexpe- pinetree and then in each vector beetle of Monochamus riencesand techniques on detectionand control. There is alternatus inJapan. The transmission is limited during clearlya greaterawareness of thisissue in Europe. earlyand mid-summer. T odeterminea temporalchange ingeneticstructure and virulence of pinewoodnematode, 005Mathematical models for spatial pattern of thenematode was sampledfrom dead Pinusdensi ora the spreadof pinewilt disease treesand from M.alternatus beetlesappearing in a P. densiora standbetween 1996 and 1998 after a heavy 1; 1 Nanako SHIGESADA ¤, Yukie MIMURA , infestation.Alleles of 30 nematodes from eachsample Fugo TAKASU 1, Kohkichi KAWASAKI 2 were determinedfor fourmicrosatellite loci. A nematode and Kazumi TOGASHI 3 isolatewas establishedfrom eachsample and inoculated on 30 P.densiora seedlingsto determine the virulence. 1 NaraW omen’s University,Kita-Uoya Nishimachi, Nara Consequently,the gene frequency was similarbetween a 630-8506,Japan nematodesubpopulation in adeadtree and those in beetles 2 DoshishaUniversity, Kyo-T anabe610-0321, Japan emergingfrom itin many cases. A veragegene diversity 3 HiroshimaUniversity, Hiroshima 793-8521, Japan [email protected] betweennematode subpopulations was smallerthan the ¤ averagegene diversity within subpopulations. Genetic Anepidemic of pine wilt disease has been spreading in distancebetween nematode subpopulations harboured in wideareas of Japan for nearlya century.The disease beetlesemerging from thesame trees was oftensmaller 124 Nematology Symposiumabstracts thanthat between those from differenttrees. The virulence thephenomenon of ‘ tiredsoils’ [ Boden Muedigkeit ] in ofnematode was low.Multiple infection may not induce a Germanyled to the isolation of fungal species from largevariation of virulenceincluding high virulent strains withincysts and females of Heteroderaschachtii from atthe end of infestation. sugarbeet elds.It was thoughtthen that some of these fungiwere pathogensof the nematodes. Throughout the 007Nematode candidates for the biologicalcontrol 20thcentury additional examples of soils suppressive ofpinewilt disease toother pathogens were described.This led to the ideathat the