Botanica Lithuanica , Volume 7, Number 1

2001 m.

In Lithuania Fraxinus excelsior dominated forests are characterised by high diversity in community structure, species composition, and sites. 155 relevés of Fraxinus excelsior stands were classified by TWINSPAN clustering. The analysis of TWINSPAN clusters revealed their high affinity to the syntaxa of Braun-Blanquet approach. Ash forest communities of Lithuania represent two alliances of the Querco-Fagatea class (Alnion incanae and Carpinion) and four associations (Alno incanae-Freaxinetum, Circaeo-Alnetum, Querco-Ulmetum, and Tilio-Carpinetum). Two variants of the ash-dominated Circaeo-Alnetum, three variants of the Querco-Ulmetum, and one variant Tilio-Carpinetum were singled out in this survey.

Keywords: Fraxinus excelsior, TWINSPAN, syntaxonomy, classification, Lithuania.

Historical conditions in the post war period in Lithuania occupied by soviets were complicated. The new soviet system influenced the development of science. Central Committee of the Communist party controlled academical teaching and researches. It was confirmed at the congress on biological problems in July–August, 1948 in Moscow. Central Committee of the Communist party approved the report by T. Lysenko. He propagated a new theory of biology and presented his researches methods and results. It was one of the doctrines on which the Soviet ideology was based. This session influenced the development of biology science and biology studies in higher schools in USSR and in Lithuania. Referring on the archival documents the analysis of botany studies in Vilnius University and Vilnius Pedagogical Institute is presented. The influence of the congress of 1948 on botany studies in the period of 1944–1950 in Lithuania is analysed.

Keywords: botany, studies, universities, institutes, Lithuania.

Attempting to explain ecological effects of nicotinic and para-aminobenzoic acids on the succession of phytoplankton, various experimental bioassays were carried out under different tropic condictions of water. After enriching the water with these vitamins, the following changes were evaluated: number of algae species, their diversity and abundance, biomass of phytoplankton, intensity of the photosynthesis of phytoplankton, also the changes in content of B group vitamins in water. After the enrichment of water with nicotinic acid, the intensity of phytoplankton photosynthesis, abundance of cyanophyces and green algae increased on the second day under mean and high eutrophic conditions and after four days the parameters were even higher. Under mean eutrophic conditions the enrichment of the water with para-aminobenzoic acids on days 2 and 4 resulted in more intensive photosynthesis of phytoplankton and clearly increased abundance of green algae. Under high eutrophic conditions both green algae and diatom abundance increased. The changes in phytoplankton coincided with obvious reduction of nicotinic and para-aminobenzoic acids, and vitamin B12 in water. The results of bioassays lead to the assumption, that nicotinic and para-aminobenzoic acids both together in a complex with vitamin B12 influence the succession of phytoplankton.

Keywords: phytoplankton, succession, vitamin, meso inosolin, biotin, pantothenic acids, thiamine, pyridoxine, nicotinic acid, para-aminobenzoic acids, vitamin B12.

The growth of fruit bodies of Boletus edulis was studied during the vegetation period of 1999 in permanent plots (forest of the Cladonio-Pinetum sylvestris type). The influence of air temperature, relative air humidity, and rainfall on the growth of fruit bodies of Boletus edulis was investigated. The changes of the growth rate of the observed fruit bodies depended on the air and soil temperatures.

Keywords: Boletus edulis, growth rate, climatic condition, Lithuania.

32 isolates of 27 species of the genus Penicillium genus were examined for their tolerance towards heavy metals: cadmium, chromium (Cr6+), cobalt, copper, nickel, and zinc. The range of fungal response to the metals was noticed to be quite wide. Some of the micromycetes like P. funiculosum 6AL, P. italicum 170SL, and P. viridicatum 11A:L were tolerant to most of the tested metals. Among the most sensitive fungi P. atramentosum 25SL and P. canescens 11ML could be pointed out. Tolerance mode and limiting metal concentrations were revealed for the most tolerant P. funiculosum 6AL and P. italicum 170SL as well as the most sensitive P. canescens 11ML and P. atramentosum 25SL.

Keywords: Penicillium, heavy metals, metal tolerance, growth inhibition.

Eight species of Hyphomycetes: Dictyochaeta fertilis (S. Hugheles et Kendrick) Hol.-Jech., D. menisporoides Hol.-Jech., D. simplex (S. Hugheles et Kendrick) Hol.-Jech., Menispora caesia Preuss, M. ciliate Corda, M. glauca Pers., M. tortuosa Corda, and Thozetella nivea (Berk. Et F. Muell.) Kuntze are reported for the first time in the country. The specimens were collected in various parts of Lithuania in 1999–2000.

Keywords: Hyphomycetes, Dictyochaeta, Menispora, Thozetella, Lithuania.

Five species of pyrenomycetes – Eutypa lejoplaca (Fr.: Fr.) Cooke, E. sparsa Romell, Melanconis spodiaea Tul., Nactria magnusiana Rehm, Winterella corylina (Tul. Et C. Tul.) O. Kuntze – are reported for the first time in Lithuania. Short descriptions and illustrations of species are provided.

Keywords: pyrenomycetes, Lithuania.