Botanica Lithuanica , Volume 3, Number 2

1997 m.

This paper continues publication of conspectus of alien plant species recorded in Lithuania. The Poaceae family in Lithuania is represented by 44 alien 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. Ten alien Poaceae species are naturalized, 29 are casuals and naturalization level of 5 species is uncertain. Distribution of 9 species is mapped. Seven Poaceae species are excluded from the list of alien plant species becouse their native distribution area reaches the territory or they were reported by error.

Keywords: alien plant species, Poaceae, conspectus, first record, distribution, naturalization, reproduction, Lithuania.

Data on the occurrence of Dactylorhiza ochroleuca in Lithuania are presented. Morphological description of this species and comparison with the related D. incarnata and its white-flowered forms are given. Distribution of D. ochroleuca in Lithuania is mapped.

Keywords: Orchidaceae, Dactylorhiza ochroleuca, D. incarnata, morphology, nomenclature, habitats, distribution, Lithuania.

The relationship of B group vitamins and phytoplankton under differen trophic conditions were investigated by bioassay experments. The scope of investigations was the seasonal – late spring (May) – succession of phytoplankton. The tests, carried out every two days indicated that clearly defined changes occurred in the composition and abudance of algae, the photosynthesis and respiration, the biomass of phytoplankton, the number of saprobic bacteria – when the level of vitamins in water fluctuated. The peaks in the development of cyanophytes coincited with clear and strong decreases in the concentrations of thiamine, pyridoxine and meso inositol in water; the peaks in green algae – with decreases in vitamin B12, para-aminobenzoic acid and biotin levels; the peaks in diatoms – decreases in para-aminobenzoic and pantothenic acids and, partially, in nicotinic acid. All the results of tests indicated that these vitamins play an important role in regulating phytoplankton succession.

Keywords: phytoplankton, succession, vitamin, meso inositol, biotin, pantothenic acid, thiamine, nicotinc acid, para-aminobenzoic acid, vitamin B12.

In the investigated six military forestries 65 rust fungi and 18 smut fungi species were found. The majority of Uredinales were heteroecious species. Fifteen species were parasites of woody plants, other – parasites of herbaceous plants. All Ustilaginales parasitized only herbaceous plants. Rusts of trees, shrubs and shrublets are widespread not only in the investigated territories, but all over Lithuania.

Keywords: micromycetes, Uredinales, Ustilaginales, military forestries, Lithuania.

Data on host plants of Melanconiales fungi in Lithunia are presented. Analysis showed that mostly plant species af the Fabaceae, Rosaceae and Salicaceae families are injured. On plants of the Rosaceae family 26, on Betulaceae – 24, on Salicaceae – 16 Melanconiales fungi species are found. On plants of other families their number is smaller. The majority of Melanconiales are narrowly specialised: develop on host plants of one species or one genus. These fungi develop on various parts of the plant. They are rarely found on roots or flowers, most commonly –on levels and branches. A list of host plants and Melanconiales inhabiting them is presented.

Keywords: fungi, Melanconiales, plant diseases, Lithuania.