Associations of cyanobacteria with actinomycetes are not investigated. The task was set in this work to study the biological aspects of coexistence of free-living cyanobacterium Anabaena variabilis with actinomycetes isolated from corraloid roots of Strangeria eriopus и Cycas micho- litzii and cyanobacterium Oscillatoria terebriformis (Ag.) Elenk. emend., which were isolated from the natural cyano-bacterial mat of Kamchatkan thermal spring, with actinomycetes, isolated from accumulating culture of cyanobacterium. Positive tropism of streptomycetes hyphes to the cya- nobacterial trichoms and cyanobacterium to streptomycetes were observed. Stimulation of growth of O. terebriformis in the associated culture with the streptomycete was marked. The increase of the fixation of nitrogen by A. variabilis and of photosynthetic activity by O. terebriformis in the associated culture with the streptomycete was marked. On this background associative interaction cyanobacteria with streptomycetes are positively discussing.

The effect of mutations in genes encoding dehydrogenases and oxidases on the resistance of the cyanobacterium Synechocystis sp. PCC 6803 to oxidative stress inducer menadione was studied. Enhanced sensitivity to menadione was observed in the mutants carrying insertions in drgA gene encoding NAD(P)H: quinone-oxidoreductase (NQR) and in ndhB gene encoding the subunit of NDH-1 complex. Menadione resistance in the mutants lacking oxidases (Ox), succinate-dehydrogenase (SDH), and NDH-2 dehydrogenase was the same as in wild type cells. The additional mutation in drgA gene increased sensitivity to menadione in NDH-2 and Ox mutants. Double mutant lacking both of SDH and NQR was not viable. Expression of drgA gene decreased during cell incubation in the dark but increased in the presence of glucose both in the dark and in the light. Under photoautotrophic growth conditions dehydrogenase activity of the cells depends mainly of the NQR and NDH-1 functions. The rate of photosystem I reaction center (P700+) re-reduction after its oxidation with white light in the presence of DCMU increased in wild type and NDH-1 mutant after addition of menadione, whereas it decreased in NQR mutant. In the presence of menadiol the reduction of P700+ was accelerated in all strains studied. These data allow suggesting that NQR provides the defense of cyanobacterial cells from the toxic effect of menadione by its 2-electron reduction to menadiol. Increased sensitivity to menadione of NDH-1 mutant may results from the inhibition of respiration and cyclic electron transport around photosystem I.

In total, 2000 P. infestans isolates collected during 1988—2004 in different regions of Russia were tested for resistance to metalaxyl. In the majority of field populations frequency of resistant strains decreased after 1993—1994. Possibly it was connected with changes in potato industry in Russia: potato producing was concentrated in small private gardens. The part of resistant strains in populations from small private patches was less than at a big commercial potato fields. Small private gardens became the great source of sensitive genotypes. Last years the part of resistant strains in the majority of field populations was less than 30%. Small number of resistant strains in population occurs even if there was no treatment with metalaxyl—containing preparations during a long time. In some populations the frequency of resistant strains increased, it would be connected with treatments. A variation in the level of resistance to metalaxyl in one clonal linage is shown. Resistant strains occurred in potato leaves and tubers, in tomato leaves; they were rare in tomato fruits. Probably, the sensitive strains affecting fruits have selective advantage.

More than 370 strains from different regions were tested for resistance to dimethomorph. In several fields isolates were collected after treatment with dimethomorph—containing preparations. Resistant strains were not detected.

As a result of the research 35 species of aquatic hyphomycetes, belonging to 21 genera and 4 unindentified taxa of genera Clavariopsis, Dactylella, Helicoon and Tetracladium was observed. For some species substrate preferences were detected. Such species as Anguillospora longissima, Tetracladium marchalianum and Fusarium aqueductum was found at different type of substrata. Only 11 species developed on pine needles while 20 species were observed on leaves. On leaves taken from water habitats 8 species of aquatic hyphomycetes were revealed (Alatospora acuminata, Angullospora aquatica, Lemonniera aquatica, Tetracladium setigerum, Tricladium angulatum, Tripospermum campelopardus, Septonema secedens, Spermospora sp.), whereas in litter 15 species was found. While grew jointly species did not demonstrate inhibitory effect on each other beside. Tripospermum campelopardus which inhibited growth of other species (Table 3). Microcyclic development of Dactylella sp. during the laboratory incubating of leaves was detected for the first time(Fig. 1). Frequency of appearance range and species diversity of aquatic hyphomycetes appeared to' be higer not on skeletinized but on intact leaves (Table 2). Aquatic hyphomycetes seasonal dynamics with two peaks of mass conidia development (vernal and more sharp autumnal) was described. Some species was observed during all the season of vegetation (Table 4). Conidial development in the laboratory incubated leave samples lasted for 30—40 days. So, recomended in literature method of incubation during 7—10 days did not allow to reveal species diversity of aquatic hyphomycetes completely.

Diffusion inside the polymeric matrix of the cell walls is a process, which determines the possibility and the rate of ion entry inside the cell. In this paper the quantitative estimation of the ion diffusion in the cell walls isolated from crustose lichen C. rangiferina (L.) F.H. Wigg. was done and its possible contribution to processes of absorption in lichen thalli was estimated. We have determined the coefficient of swelling of the cell wall matrix and the diffusion coefficient of the organic cation in the lichen cell walls. Our results show that lichen cell walls characterize by higher cross-linking degree and by smaller diffusion coefficient than plants.

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Threshold and lethal concentration of Hg, Cd, Pb and Cu had been evaluated for dominant species of marine micro-algae. Algae with high specific surface are the most sensitive to the metal action. There are resilience species surviving at long range between low threshold and high lethal level of metal and conserving growth after toxic stress. Resistance species could survive at high threshold and high lethal metal concentration. The ratio of sensitive and resistant micro-algae to heavy metals can be used for marine water quality monitoring.

Microcolonies of bacteria living in a common fibrous matrix and dyes rust color with precipitating iron oxides are described. They are isomorphous (identical at sight) but represent different systematic groups. These microcolonies live both in fresh water and also present in soil moisture and activated sludge in airtanks. Their populations becomes exceedingly large, when biological transformation of organic substances due to the saturation of water with poorly oxidialing substances like soluble humus fractions, becomes disordered.
Data on the dynamic of the population of the microcolonies is used in new hydrobiological control processes of wastewater treatment and self-purification natural water — bioestimate. For distinguishing the microcolony the term siderotheca is suggest.

Comparison of morphometric data of pygmy shrews (Sorex minutus Linnaeus, 1766) from two geographical locations in the North of European Russia, standing 1000 kilometers apart, was conducted. Comparatively high stability of all indexes is registered.

In autumn period from March till May 1988 in Patagonium shelf and slope zones, the system of waters current modified and water temperature decreased. The biomass of seston and abundance of zooplancton decreased simultaneonsly, especially of subantarctic species Calanus simillimus. The zooplancton organisms started going down to deeper water layers. Antarctic species Rhincalanus gigas was common in upper layers in March. In May, R. gigas was rare and occured at larger depths. Subtropical zooplancton species dominated in shelf zone while subantarctic species dominated in the slope zone within the Folkiand current.
In May, the abundance of the shelf speciesin the slope zone increased because of wcakining of Falkland current and is dislocation to the east. The zooplancton biomass and abundance increased at the zone of water divergence in the cast and at the slope frontal zone in the west.