Leonid A Ivanov

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Recent studies of transgenic poplars over-expressing the genes gsh1 and gsh2 encoding γ-glutamylcysteine synthetase (γ-ECS) and glutathione synthetase, respectively, provided detailed information on regulation of GSH synthesis, enzymes activities and mRNA expression. In this experiment, we studied quantitative parameters of leaves, assimilating tissues,(More)
Changes in the structural characteristics of mesophyll induced by shading were investigated in ten species of wild plants of diverse functional types. In all plant types, shading reduced leaf thickness and density by 30–50% and total surface of mesophyll, by 30–70%. The extent and mechanisms of mesophyll structural rearrangement depended on the plant(More)
Construction cost (CC) of leaves was studied in 73 boreal plant species differing in ecological strategy. CC is the energy cost, expressed as glucose weight, of the plant weight unit formation. The perennial species that exhibited the stress-tolerant (S) type of strategy had the highest, whereas the annual plants of the ruderal type (R) of strategy had the(More)
In the boreal zone of the Middle Urals, biomass structure was studied in 35 species of wild plants with different ecological strategies according to Grime and Ramenskii (competitors, ruderals, and stress-tolerant plants). Plants belonging to these groups proved to differ considerably in the absolute plant weight and the quantitative contributions of the(More)
430 The specific surficial density of a leaf (SSDL or dry weight of the leaf area unit) is a fundamental charac teristic of a plant [1, 2] and is used in global models of the Earth’s vegetation [3]. The SSDL is related to many aspects of plant growth and development [4] and correlates with such parameters as the level of net pho tosynthesis [5], content of(More)
Construction costs (CC) and parameters of leaf structure (specific leaf weight, dry matter content, volume of photosynthesizing cells, and the number of cells per leaf area unit) were determined for 19 species of aquatic higher plants. The CC of 1 g dry matter varied from 0.98 g glucose in Lemna gibba L. to 1.48 g glucose in Nuphar pumila (Timm) DC. and(More)
Changes in some leaf characteristics: leaf mass area (LMA), content of photosynthetic pigments and nitrogen in the leaves, leaf mass ratio (LMR) and leaf area ratio (LAR) were investigated in steppe plants of the Volga land along the gradient of aridity. When drought stress became stronger, the content of chlorophylls in the leaves, LMR and LAR decreased,(More)
The isotope ratios δ13C and δ15N and the contents of nitrogen, carbon, and mineral substances have been studied in the leaves of Ephedra sinica, Allium polyrhizum, and Stipa glareosa plants growing separately or together under arid conditions of the Gobi (Mongolia). The contents of nitrogen, mineral substances, and δ15N have proved to decrease when these(More)
Leaf chemical composition of 19 hydrophytes was studied. The content of carbon, nitrogen, nonstructural carbohydrates, organic acids, minerals, and water was determined. Hydrophytes were shown to contain less carbon (below 410 mg/g dry wt in 60% species) than terrestrial plants. Hydrophytes and terrestrial plants did not differ in the nitrogen concentration(More)
The structural and functional parameters and productive characteristics of ten species of Mongolian forest steppe shrubs were studied. The shrubs had 5- to 10-fold difference in size and aboveground biomass and 1.5- to 2-fold difference in leaf parameters. The emphasis was placed on two groups of structural and functional parameters related to the(More)