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.

Restriction analysis of amplified ribosomal ITS sequences has provided species-specific fragment patterns for nematodes of several genera, including Bursaphelenchus. We used restriction enzymes RsaI, HaeIII, MspI, HinfI and AluI to produce ITS-RFLP reference profiles of 44 Bursaphelenchus species, including two intraspecific types in each of B. mucronatus and B. leoni. In addition, reference profiles of Aphelenchoides stammeri and Ruehmaphelenchus asiaticus were produced. Reference profiles of six species are shown here for the first time. Identical ITS-RFLP patterns were usually obtained from different isolates and from individual specimens of the same species. However, in the case of B. 'corneolus', B. lini, B. singaporensis and B. sexdentati, additional bands in the patterns of certain isolates or individual nematodes were observed which may be explained by ITS sequence microheterogeneity, i.e., the presence of ITS sequence variants within the number of rDNA tandem repeats. Since these 'extra' bands appeared only with one out of the five restriction enzymes employed, they did not seriously impair identification of species based on the overall reference patterns. ITS-RFLP analysis has proved valuable for differentiation of the pathogenic pine wood nematode, B. xylophilus, from related species. In many recent descriptions of new Bursaphelenchus species, ITS-RFLP profiles have been used as additional species identification criteria. Comparison of profiles from isolates of many different origins has provided new information on intraspecific types or genetically distinct provenances of several Bursaphelenchus species.

A linkage map of carrot (Daucus carota L.) was developed in order to study reproductive traits. The F2 mapping population derived from an initial cross between a yellow leaf (yel) chlorophyll mutant and a compressed lamina (cola) mutant with unique flower defects of the sporophytic parts of male and female organs. The genetic map has a total length of 781 cM and included 285 loci. The length of the nine linkage groups (LGs) ranged between 65 and 145 cM. All LGs have been anchored to the reference map. The objective of this study was the generation of a well-saturated linkage map of D. carota. Mapping of the cola-locus associated with flower development and fertility was successfully demonstrated. Two MADS-box genes (DcMADS3, DcMADS5) with prominent roles in flowering and reproduction as well as three additional genes (DcAOX2a, DcAOX2b, DcCHS2) with further importance for male reproduction were assigned to different loci that did not co-segregate with the cola-locus.

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