Oats are one of the most useful and widespread cereal crops in the world. In permafrost conditions (Central Yakutia), based on metabolic changes in late summer-sown oat plants ( L.), the key processes involved in the cold acclimation of a valuable cereal species were identified.
View Article and Find Full Text PDFCyanobacteria are thought to be responsible for pioneering dioxygen production and the so-called "Great Oxygenation Event" that determined the formation of the ozone layer and the ionosphere restricting ionizing radiation levels reaching our planet, which increased biological diversity but also abolished the necessity of radioprotection. We speculated that ancient protection mechanisms could still be present in cyanobacteria and studied the effect of ionizing radiation and space flight during the Foton-M4 mission on Synechocystis sp. PCC6803.
View Article and Find Full Text PDFThe effect of a dangerous toxic substance, methylmercury, on light dependence curves of chlorophyll fluorescence in Chlamydomonas moewusii was studied. We found low concentration of methylmercury (10(-7) M) to cause a decrease in the relative rate of the non-cyclic electron transport activity of PS 2, a decline in the maximum utilization of light energy (α), and a decline in the saturation light intensity (E(s)). Non-photochemical fluorescence quenching increased after short-term exposure and decreased in the course of prolonged incubation.
View Article and Find Full Text PDFThe results of investigations of three Moskva River sites with different degree of pollution using a complex of microbiological characteristics and the parameters of chlorophyll a fluorescence are presented. We determined that the bacterioplankton seasonal dynamics at less polluted waters (Tushino and Vorobyovy Gory) were similar and differed significantly from one in more polluted waters (Dzerzhinskii). The number of bacteria with active electron transport chain, as well as their share in the bacterioplankton structure, was higher in the water of Dzerzhinskii (average annual values of 0.
View Article and Find Full Text PDFThe technique for recording of chlorophyll a fluorescence induction kinetics has been used for assessment of the physiological state of leaves of tillet (Tilia cordata), pendent white birch (Betula pendula), American arborvitae (Thuja occidentalis) in urban environments. Different sensitivity of plants to adverse growing conditions was observed. The most sensitive JIP test parameters such as PI(ABS), F(V)/F(0), F(V)/F(M), R(fd) are determined to be used as indicators of the physiological state of urban phytocenosis.
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