Infective-stage juveniles of entomopathogenic nematodes of the genera Steinernema and Heterorhabditis were recovered by direct extraction from 36% of a total of 111 soil samples collected in various biotopes from different regions of Slovakia. The rate of prevalence was highest in forest soil (58%). On the basis of morphological characters of the infective juveniles eight Steinernema and one Heterorhabditis species were distinguished. Steinernema affine, S. intermedium and S. feltiae were most prevalent (together 74% of all records). The other species of Steinernema encountered were S. kraussei, S. carpocapsae, S. bicornutum, a species of the S. glaseri group and an undescribed species earlier recorded from Germany. In 11 of the 40 soil samples positive for entomopathogenic nematodes mixtures of two to four species were present. Several species showed a distinct habitat preference, e.g., S. affine for arable soil and S. intermedium for woodland and river bank vegetation with trees. A preference for certain soil types was less apparent. Untersuchungen uber Vorkommen und Verbreitung entomopathogener Nematoden in der Slowakischen Republik - Insgesamt 111 Bodenproben, die in unterschiedlichen Biotopen aus verschiedenen Regionen der Slowakei entnommen worden waren, wurden auf entomopathogene Nematoden untersucht. Infektionsjuvenile der Gattungen Steinernema und Heterorhabditis waren uber eine direkte Extraktion der Nematoden aus dem Boden in 36% aller Proben nachweisbar. Der hochste Anteil "positiver" Proben fand sich bei Proben aus Waldern (58%). Anhand morphologischer Merkmale der Infektionsjuvenilen waren acht Steinernema Arten und eine Heterorhabditis-Art differenzierbar. Steinernema affine, S. intermedium und S. feltiae waren die haufigsten Arten (insgesamt 74% aller Nachweise). S. kraussei, S. carpocapsae, S. bicornutum, eine Steinernema-Art der S. glaseri-Gruppe und eine noch unbeschriebene Steinernema-Art (bereits aus Deutschland bekannt) und Heterorhabditis sp. wurden seltener gefunden. In 11 aller 40 "positiven" Proben kamen zwei bis vier Arten nebeneinander vor. Einige der Arten zeigten eine deutliche Bevorzugung bestimmter Biotoptypen, so S. affine von Acker- und Gartenboden und S. intermedium von Waldern und Ufervegetation mit Baumen. Eine Bevorzugung bestimmter Bodenarten war dagegen kaum erkennbar.

The plant-parasitic nematode Longidorus poessneckensis from the Czech Republic was morphologically and molecularly characterised. Molecular analyses were carried out using mitochondrial DNA (cytochrome c oxidase subunit 1-cox1) and ribosomal DNA (ITS2-second internal transcribed spacer, 18S gene and D2/D3 expansion segments of the 28S gene), which were amplified and sequenced. Phylogenetic relationship of L. poessneckensis with three morphologically closely related species, i.e. L. macrosoma, L. helveticus and L. uroshis, was inferred by using maximum likelihood and maximum parsimony methods, with a female of Xiphinema diversicaudatum and a bivulval female of X. vuittenezi as outgroups. All multiple alignments yielded similar basic trees supporting the uniqueness of L. poessneckensis and the validity of the four Longidorus species identified using morphological characters. Phylogenetic analyses revealed that L. poessneckensis is more closely related to L. macrosoma and L. helveticus than to L. uroshis. High inter-population diversity (19%) was observed across the cox1 gene between two populations of L. poessneckensis.

A total of 61 nematode species belonging into 48 genera was identified in soil of nine localities of hop gardens in Slovakia. From free living soil nematodes the most abundant were the genus Rhabditis -eudominant taxon, species Aphelenchus avenae -dominant taxon, the species Cephalobus persegnis, Chiloplacus propinquus, Aglenchus agricola, Nothotylenchus acris, Aporcelaimellus obtusicaudatus and genus Eudorylaimus were subdominant taxa. Only ten species of plant parasitic nematodes were observedDitylenchus dipsaci, Bitylenchus dubius, Merlinius brevidens, Rotylenchus robustus, Helicotylenchus canadensis, H. digonicus, Pratylenchus penetrans, P. pratensis, Heterodera humuli, and Paratylenchus bukowinensis. Bitylenchus dubius and Merlinius brevidens belonged to dominant taxa, the species Heterodera humuli and Helicotylenchus digonicus to subdominant taxa. The occurrence of Heterodera humuli cysts was recorded at all localities studied, and the occurrence of H. humuli larvae in soil during autumn indicates that possibly more than one generation of the parasite have developed within one vegetation period. The proportion of individual trophic groups in nematode communities of hop gardens was characterised by the prevalence of bacterial feeders followed by plant parasites. The ecological characteristics used for ecological evaluation, especially Maturity Index and Plant Parasitic Index/ Maturity Index, indicate a more disturbed environment. Although hop is a perennial plant, the structure and ecology of its nematode communities is more similar to the agricultural ecosystems with a higher level of agricultural practices.Key words: nematode communities; hop gardens; Slovakia IntroductionThe wild hop, Humulus lupulus L., can be found freely in nature; commercial hop cultivars used for beer production ………….are grown in suitable climatic and soil conditions throughout the world. The first records of nematodes in soil of hop fields were associated with the occurrence of Heterodera humuli in Germany Voigt (1894) and, subsequently, in England (Percival, 1895). To date, research on nematodes linked with hops had focused mainly on this speciesconsidered to be the dominant parasite of hop. Previous investigations studied the geographical distribution of H. humuli e.g. in the Czech Republic (Šály & Kříž, 1961), in Switzerland (Hogger, 1988), in Spain Lopez -Robles (1995), in England (Mende & McNamara (1995a), in Germany (Eppler, 1999), explored the biology and a life cycle of H. humuli (Mende & McNamara (1995a,b), pathological effect of H. humuli on hop plants connected with different varieties (Mende & Mc. Namara, 1995b;Hafez et al., 1999), and nematodes as vectors of plant viruses by e.g. Valdez et al. (1974) and Barbez (1982). The other nematodes of the rhizosphere of hop gardens were investigated by Malan et al. (1991), Eppler (1999), and Hay and Pethybridge (2003 and others. In spite of the substantial investigation of communities of free living and plant parasitic nematodes of various agroecosystems and natural ecosystems ...

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Forty plant parasitic nematode species were identified in soil of fruit orchards in the southeastern and southwestern areas of the Danubian Lowlands and East Slovak Lowland, characterised by light sandy soil of riverine origin, locally combined with drift sand landscape. They were <i>Ditylenchus dipsaci</i>, <i>Helicotylenchus canadensis</i>, <i>H. digonicus</i>, <i>H. dihystera</i>, <i>H. multicinctus</i>, <i>Rotylenchus agnetis</i>, <i>R. fallorobustus</i>, <i>R. goodeyi</i>, <i>Rotylenchulus borealis</i>, <i>Pratylenchus crenatus</i>, <i>P. penetrans</i>, <i>P. pratensis</i>, <i>P. thornei</i>, <i>Zygotylenchus guevarai</i>, <i>Pratylenchoides laticauda</i>, <i>Meloidogyne hapla</i>, <i>Bitylenchus dubius</i>, <i>Tylenchorhynchus cylindricus</i>, <i>Merlinius nanus</i>, <i>Macroposthonia antipolitana</i>, <i>M. rustica</i>, <i>M. xenoplax</i>, <i>Paratylenchus bukowinensis</i>, <i>P. elachistus</i>, <i>P. nanus</i>, <i>P. projectus</i>, <i>Longidorus elongatus</i>, <i>L. euonymus</i>, <i>L. juvenilis</i>, unidentified <i>Longidorus</i> sp., <i>Xiphinema diversicaudatum</i>, <i>X. italiae</i>, <i>X. pachtaicum</i>, <i>X. taylori</i>, <i>X. vuittenezi</i>, <i>Trichodorus primitivus</i>, <i>T. sparsus</i>, <i>T. viruliferus</i>, <i>Paratrichodorus macrostylus</i> and <i>P. pachydermus</i>. Many of the observed species are phytopathologically important parasites of fruit trees and some are also vectors of plant viruses. The frequency of occurrence, dominance and abundance of individual species were determined.

A study on the seasonal fluctuation of nematode population was conducted during three vegetation periods (2005 – 2007), at 20 and 40 cm soil depth, from May to October, in a hop garden at Nemšová (Slovak Republic). The seasonal fluctuation of the nematode population was related to temperature and rainfall. At 20 cm soil depth of each year, the largest nematode population was recorded in July, and the smallest from July to October. At 40 cm soil depth, nematode abundance was not significantly different between the years 2006 and 2007. In general, at the same depth, a decrease of nematode abundance was observed from May to October. The soil nematode community was rich in bacteriovorous nematodes, especially in the top 20 cm soil. The genus Rhabditis was the eudominant taxon at both soil depths. This genus with the genera Cephalobus, Heterodera, Merlinius and Aglenchus represented the 50 % of the total nematode population at 20 cm soil depth and with the genera Cephalobus, Helicotylenchus, Heterodera and Merlinius represented the 52 % of total nematodes abundance at 40 cm depth.

264 SummaryThe record of occurrence of Longidorus poessneckensis Altherr, 1974 in forest soils with Betuleto-CarpinetoQuercetum in geographically specific conditions of a hilltop contributes to the broadening of ecological knowledge about this species. To date, the species was considered to prefer the habitats along river banks -narrow or large valleys and plains. The ecological, morphometrical and molecular characteristics of recorded L. poessneckensis are presented here.

270 SummaryThe species Longidorus profundorum Hooper, 1965 was for the first time recorded in the territory of Slovakia. It was observed in the rhizosphere of Fraxineto-Quercetum forest of riverine plain along Moravia River in south-western part of country, close to boundary with Austria. Morphometrics of females, males and four juvenile stages, morfological and molecular characteristic of Slovakian specimens are presented.