Russulales-2010 Scripta Botanica Belgica 51: 64-76 (2013) Russulaceae (Russulales, Agaricomycotina, fungi) in the thermophilous oak forests of W Slovakia Slavomír ADAMčÍK1*, Soňa JANčOVIčOVÁ2 & Milan VALACHOVIč1 1 Institute of Botany, Slovak Academy of Sciences, Dúbravská cesta 9, SK – 845 23 Bratislava, Slovakia 2 Comenius University in Bratislava, Faculty of Natural Sciences, Department of Botany, Révová 39, SK – 811 02 Bratislava, Slovakia * Author for correspondence: [email protected] Abstract. – The diversity and frequency of Russulaceae basidiomata (Lactarius, Russula) were studied in the phytocoenologically defined oak forests of three selected localities in the western part of Slovakia in years 2005–2009. Based on the ecological amplitude and the frequency, common and rare, as well as characteristic species were defined for each locality. Taxonomic problems within the species complexes of Russula decipiens, Russula rutila and Russula glo­ bispora are discussed. Résumé. – Résumé. – Russulaceae (Russulales, Agaricomycotina, Fungi) dans les chê- naies thermophiles de l’ouest de la Slovaquie. Durant les années 2005–2009, la diversité et la fréquence des carpophores de Russulaceae (Lactarius, Russula) ont été étudiées dans des forêts de chêne, définies d’un point de vue phytocoenologique, de trois localités sélectionnées de l’ouest de la Slovaquie. Sur base de l’amplitude écologique et de la fréquence, des espèces communes et rares, de même que des espèces caractéristiques, ont été définies pour chaque localité. Les problèmes taxonomiques dans les complexes d’espèces de Russula decipiens, Rus­ sula rutila et Russula globispora sont discutés. [Résumé ajouté par l’éditeur] Key words. – Russula, Lactarius, biodiversity, ecology, taxonomy INTRODUCTION tion and altitude from ca. 200 to 750 m. They are dominated by Quercus species, but Carpi­ Thermophilous oak forests cover approximate- 2 nus betulus is another native ectomycorrhiza- ly 4 130 km (8.3%) of the area of Slovakia forming tree that grows there. The presence of according to the map of potential vegetation of other ectomycorrhizal trees is exceptional and Slovakia (Maglocký 2002). Their recent area is strongly reduced because of agricultural man- caused by extreme values of some field char- agement, especially in the areas with suitable acteristics, e.g. the occurrence of Betula on soil and terrain characteristics. The most dis- acid soil, Populus tremula on moist places, etc. tant natural oak forests occur in the mountains Some management activities help preserving of the south-western part of Slovakia, namely the natural character of these forests: trees are in the Štiavnické vrchy Mts., Pohronský Ino- not cut in large areas; new trees are not planted, vec Mts. and Tríbeč Mts. Thermophilous oak but grow from seedlings germinating naturally forests occur there with SW, S or SE exposi- or from sprouts on stumps. 2 Russulales-2010 – Scripta Botanica Belgica 51 (2013) We have studied the diversity and frequency Horné Majere – The locality is a terrace above of two agaricoid genera of family Russulaceae a small stream, lined on one side by an almost Lotsy – Lactarius Pers. and Russula Pers. – in vertical slope and on the opposite side by a for- the phytocoenologically defined oak forests of est road with natural surface and a meadow. It nine selected localities in the western part of is located in the central part of the geological Slovakia, during the years 2005–2009. The aim complex, at highest altitude. This locality is the of our study was (i) to compare Russulaceae smallest and the most homogeneous one. diversity and basidiomata frequency on the selected localities, and (ii) to define selected Phytocoenological observations groups of the genus Russula morphologically. Only some of our visits were fully successful Phytocoenological observations are in ac- with sufficient number of recorded species cordance with Zürich-Montpellier’s school and collected basidiomata, because we did not Braun-Blanquet 1964, Westhoff and van der foray in the suitable season during some years Maarel 1978). Geographical coordinates are and/or climatic conditions were unfavorable. situated approximately in the middle of the As our project is still running, we present the localities. Nomenclature and abbreviations of results only from three selected localities, with habitats follow Stanová & Valachovič (2002). the most successful visits. The nomenclature of vascular plants follows Marhold & Hindák (1998). MATERIAL AND METHODS Identifications of fungi Brief description of the studied sites Taxa of the genus Lactarius were identified ac- Taxa of Lactarius and Russula were collected cording to monograph by Heilmann-Clausen in three selected localities of the W part of Slo- et al. (1998); Russula taxa with several pub- vakia – Obyce, Horné Majere and Sovia dolina lications, in most cases books by Romagnesi – in the years 2005–2009 (for detailed charac- (1967) and Sarnari (1998, 2005). Due to sev- teristics of the localities see text below). All eral taxonomic problems, some of our identifi- localities are situated in the area of Štiavnické cations remain still uncertain and limited to the vrchy stratovolcano which is mostly formed by level of a species complex. We labeled them as andesites and tuffs in underground. The pH of “cf.” and treat them as insufficiently identified soil depends on its position: Obyce and Sovia morphotypes with expected taxonomical value. dolina are situated on a marginal part of the Specimens are deposited in the herbarium SAV. geological complex at lower altitudes, which is characterized by less acidic soil; Horné Majere The frequency of basidiomata situated in its central part has more acidic soil. The frequency of basidiomata was estimated All sites are managed forests with trees form- in accordance with the following scale (cf. ing tree layer in approximately same age. Adamčík et al. 2006): Obyce – With W to SW exposition, the locality • 1 = infrequent (1 collection with 5 and < ba- is situated in the wide valley of Žitava River sidiomata) (ca. 1 km from the river) and has relatively • 2 = moderately frequent (1 collection with 5 smooth and plane relief. and > basidiomata or more collections with < than 5 basidiomata) Sovia dolina – The locality is in the valley of a • 3 = frequent (more collections and at least 1 stream on SE exposition, which has rough ter- with > than 5 basidiomata) rain with slopes of various angles and is domi- nated by a small hill in the centre. It is very heteromorphous; close to the stream, there is a RESULTS flat terrain dominated by Carpinus betulus. Up Phytocoenological characteristics of the to the hill, there is relatively steep slope, domi- studied localities nated by Quercus, disconnected by a small pla- teau. The locality is crossed by two forest roads Obyce – Thermophilous oak forest (Quercus without artificially improved surface. cerris and Q. petraea agg.) grows on well de- S. Adamčik et al., Oak forest Russulaceae of W Slovakia 3 Table 1 – Characteristics of localities of research. + = lower, ++ = medium, +++ = higher Characters / Locality Obyce Horné Majere Sovia dolina Coordinates (latitude/ 48°26´25´´N; 18°28´55´´E 48°22´55´´N; 18°54´01´´E 48°19´33´´N; 18°38´59´´E longitude) Slope W S SE Altitude (m) 320-400 450-460 340-390 +++ + ++ Acidity of soil + +++ ++ Depth of soil +++ + ++ Vegetation type oak woods on deeper soil oak woods with Quercus oak woods with Carpinus cerris on shallow soil betulus, slightly nitrophilous β-diversity of vegetation ++ + +++ Diagnostic vascular Euonymus europaeus Carex montana Ajuga reptans plants Rhamnus cathartica Coronilla vaginalis Carpinus betulus Lathyrus tuberosus Genista tinctoria Cruciata glabra Euphorbia cyparissias Lychnis viscaria Galium schultesii Sorbus torminalis Hieracium lachenalii Tanacetum corymbosum Veronica officinalis Viola reichenbachiana veloped soils. Slightly exposed slopes (5-7°) lis, Tanacetum corymbosum or Trifolium alpes­ oriented SW-W provide optimal conditions for tre (table 1). Taxa of Russulaceae are listed in oak trees. The height of the trees is about 25 table 2. m. The herbaceous layer is rich in species and Sovia dolina – The light slope (5-7°) at the covers around 80% of the surface. The shrub bottom of the wet valley. The dominance of layer is poor; represented by young trees of Carpinus betulus indicates the nitrophilous Acer campestre, Carpinus betulus and Prunus character of the locality while Quercus cerris avium, and several shrubs, e.g. Euonymus eu­ is only additional tree. Several stones (andes- ropaeus, Rhamnus cathartica and Rosa canina ite) cover the locality. The cover of herb layer agg. Thermophilous species, e.g. Astragalus (40%) is evidently less dense than in the locali- glycyphyllos, Clinopodium vulgare, Fragaria ties 1 and 2. In the herb layer, there are numer- viridis, Lychnis viscaria and Viola mirabilis ous taxa characteristic of beech forests, such as dominate the herb layer, but some mesophilous Dentaria bulbifera, Galium schultesii, Mycelis and nitrophilous taxa also occur, e.g. Cruciata muralis, Symphytum tuberosum and of course laevipes, Galium aparine and Torilis japonica. juvenile saplings of Fagus sylvatica (table 1). The litter layer is thick; mosses rarely occur Taxa of Russulaceae are listed in table 2. (table 1). Taxa of Russulaceae are listed in table 2. Russulaceae diversity Horné Majere – The flat ridge is covered by trees of Quercus cerris and partly also by Our data are based on four successful field ex- Q.