Botanica Lithuanica, Volume 4, Number 2

1998 m.

This paper continues publication of the conspectus of alien plant species recorded in Lithuania. The Lamiaceae family in Lithuania is represented by 20 and Scrophulariaceae by 14 alien plant species. Data on the first record, distribution, habitats, level of naturalization, means of immigration and biology (time of flowering, fructification and reproduction) of each species are presented. Fifteen alien species described in the present paper are naturalized, 18 are casuals and naturalization level of 1 species in Lithuania is uncertain. Distribution of 4 species is mapped. Six species belonging to these families are excluded from the list of alien plant species.

Keywords: alien plant species, conspectus, Lamiaceae, Scrophulariaceae, distribution, naturalization, reproduction, Lithuania.

The most numerous and taxonomically complicated genus Hieracium L. was presented in Lithuania only by 8 species aggregates, belonging to the subgenus Hieracium (= Hieracium L. s. str.), and by 26 species, belonging to the subgenus Pilosella Tausch (= Pilosella Hill). In 1995, with the preparation of the material for the third volume of the „Flora of the Baltic Countries”, a revision of the Lithuanian herbarium collections of this genus was made. After the revision of herbarium material 40 species of the genus Hieracium growing in Lithuania were revealed. In this paper a key for identification and conspectus of Hieracium L. s. str. species occurring in Lithuania are presented.

Keywords: Hieracium, taxonomy, flora, Lithuania.

Remarks about lichen flora of well-preserved deciduous forest in Borecka Primeval Forest in north-eastern Poland are given. The lichens – old forest indicator species, e.g. Chaenotheca brachypoda, C. chlorella, Lobaria pulmonaria, Pyrenula nitida and Thelotremalepadinum were collected. Three taxa new to Poland, i.e. Micarea botryoides, Scoliciosporum pruinosum and Trapelia corticola were recorded. Some lichens (e.g. Biatora fallax, Chaenotheca laevigata, Anisomeridium nyssaegenum, Biatoridium monasteriense) rare in Poland are noted.

Keywords: lichens, old forest indicator species, deciduous forests, Poland.

Phytoplankton in the lakes of Netiesa range was investigated in July, 1996. Totally 196 algae species, 45 varieties and 11 forms were recorded. 11 species were identified up to the genus rank. Green algae (Chlorophyta) and diatoms (Bacillariophyta) dominated in the studied phytoplankton, respectively they comprised 44.4 % and 30.7 % of the recorded taxa. Other groups are presented in a decreasing order: Cyanophyta – 13.6 %, Euglenophyta – 4.94 %, Chrysophyta – 3.04 %, Pyrrophyta – 2.28 %, Xanthophyta – 0.76 %. The most frequent species (44 ), found in more than 50 % of all examined lakes, were as follows: Asterionella formosa Hassall, Ceratium hirundinella (O. F. Müller) Schrank, Cocconeis placentula Ehrenb., Dinobryon divergens Imhof, Epithemia turgida (Ehrenb.) Kützing, Fragilaria crotonensis Kitton, Gomphonemaacuminatum Ehrenb., Rhopalodia gibba (Ehrenb.) O. F. Müller, Synedra capitata Ehrenb. Most of all recorded algae species (155) were rare ones, which were found only in one lake. These species comprised 59 % of all recorded taxa (e.g., Surirella robustra Ehrenb., Cosmarium pseudoprotuberans Kirchner, Tetradesmusscenedesmoides (G. M. Smith) Chodat, etc). Gomphonema clevei Fricke was found for the first time in Lithuania.

Keywords: phytoplankton, species structure, distribution, abundance, level of trophy, lakes of the Netiesa range, Dz?kija National Park, Lithuania.

Results of lichenological trip held during the 13th International symposium of lichenologists and mycologists of the Baltic states in the territory of ?emeri National Park are presented in the paper. 148 taxa of lichens and allied fungi were found. Six species are reported for the first time from Latvia: Clypeococcum cetrariae, Lecanora saligna, Peltigera ponojensis, Pycnidiella resinae, Strangospora pinicola, Vouauxiella lichenicola.

Keywords: lichens, lichenicolous fungi, resinicolous fungi, National Parks, Latvia.

Radioactive Cs was investigated in the samples of 38 macromycete species, mosses (unspecified), Calluna vulgaris, Vaccinium myrtillus, lichens (Cladonia subgenus Cladina) as well as forest litter, upper (0–5 cm) and lower (5–20 cm) soil layers. Samples were collected during the period of 1992–1995 in the regions of highest, medium and lowest pollution with Chernobyl radiocesium. Activity of radiocesium was established in the most common macromycete species of Lithuania. Dependance of Cs activity in fungi upon habitat and substrate is discussed and dynamics in the fruit bodies of fungi during 1986–1995 is presented. Comparative investigations on radiocesium were carried out in fungi and some forest plants collected at the same time under identical conditions.

Keywords: radioactive cesium, concentration, dynamics, macromycetes, Lithuania.

Results of biological investigations on wide-spread pathogenic fungi Cercospora acetosellae, C. armoraciae, C. beticola, C. carotae, C. meliloti, C. microsora, C. radiata, C. rautensis and C. zonata are presented. The fastest germination of conidia and colony growth of the most harmful Cercospora fungi in Lithuania occur at a temperature of 22–27 oC. Short-term irradiation by UV-rays stimulates the development of conidia and inhibits the growth of mycelium at the same time. Wide-spread plant pathogens C. microsora and C. meliloti in vitro showed the best growth on natural media (pH-5–8). C. microsora is harmful under variable climatic conditions: wet and warm or hot summer as well as cool summer, since this plant pathogen is active even at 17 oC. At this temperature (pH 6.5) pectines and albumens are most intensively decomposed. Amylases are the most active under the temperature of 22 oC and cellulasis have high endogliuconasic activity even at 30 oC (pH 6.5). Improperly-balanced fertilization might stimulate conidia formation and spreading of Cercospora caused leaf spot. Among investigated fungicides in vitro the most effective against C. microsora were 2 % Bordeaux solution and 0.2 % sportak, among fungicides used against C. meliloti – 1.5 % TMTD and 1 % burgundy solution. Some antibiotics (tetraciklin together with nistatin, and nistatin) affect the plant pathogens causing Cercospora leaf spot.

Keywords: fungi, Cercospora, biological properties, plant pathogens, Lithuania.

The data on previously unknown lichen collection from Lithuania is presented. It includes 24 lichen species, collected during 1933–1939 in the territory of Vilnius, Svencionys, Salcininkai and Kupiskis districts. Unknown before historical localities of two Red Data book species Evernia divaricata and Usnea glabrescens are registered. Specimen of Usnea fulvoreagens is the first herbarium voucher of this species from Lithuania. Two species of lichenicolous fungi – Abrothallus parmeliarum and Nesolechia oxyspora – are new to Lithuania.

Keywords: Lichens, herbaria, Lithuania.