Effect of soil type and overgrowth time on agrochemical parameters of fallow lands located along the accumulation trend of material–energy flow

It has been shown that changes in agrochemical parameters of fallow lands depend on the type of soil and the time of overgrowth. A gradual acidification of the postagrogenic layer, its differentiation into two sublayers by the contents of humus and total exchangeable bases, and a decrease in the content of mineral nutrients are observed in overgrown agrosoddy-podzolic soils. In agrogray soils, these processes are less intense.     

Molecular approaches in identifying leaf rust resistance genes in Russian wheat varieties

Russian soft wheat varieties are screened with the use of molecular markers of Lr genes. A low genetic diversity is found among leaf rust resistant varieties, in which genes Lr9 and Lr19 dominate. There are no highly effective genes Lr25, Lr29, and Lr39(41) and adult plant resistance genes Lr37 and Lr21 in the studied varieties. Among genes with limited effectiveness, the most prevalent are genes Lr10 and Lr26, respectively in 45 and 10% of the varieties.     

Results of experiments to develop technology and machines for producing plant industry products under drought conditions

In comparative tests of domestic and foreign machines under the acute drought conditions in 2010, the best indices were obtained with the use of domestic cultivators and planters. A set of domestic machines for producing grain by drought-resistant technology is given.     

Overgrowing of fallow soddy podzolic soils as a factor of modern pedogenesis

The research shows that overgrowing of agricultural soddy-podzolic soils in the taiga-forest zone leads to differentiation of the arable layer into two sublayers. Sod pedogenesis is superimposed on its upper part, which leads to an increase in its humus content and total exchangeable bases and a decrease in soil fertility. A podzolic process is imposed on its lower part, which causes a reduction in its humus content and an increase in the acidity of the entire postaprogenic layer. After 40 years of overgrowing, these sublayers become close to the horizon AY (soddy horizon) and to the EL (eluvial horizon) of virgin soils in a set of their properties.     

Results of endocrinologic studies in culture media after coculture of bovine oocytes with granulosa cells

The steroid hormones progesterone (P.), and testosterone (T.) were radio-immunologically determined in 108 medium samples, following co-culturing of bovine oocytes with granulosa cells. P. and T. values recorded from a control group were lower with significance than those recorded from co-culturing groups, that is 72 +/- 21 ng/ml and 264 +/- 84 pg/ml as compared to 208 +/- 138 ng/ml and 2,168 +/- 1,595 pg/ml in the oocyte plus fresh granulosa cell co-culturing group as well as 364 +/- 215 ng/ml and 825 +/- 233 pg/ml in the oocyte plus pre-incubated granulosa cell co-culturing group. These rises were accompanied by decline in maturation rate, increase in oocyte degeneration, and rises in the rates of fertilisation and segmentation.     

The morphology of cells and the biomass of microorganisms in the buried paleosols and modern steppe soils of the Lower Volga region

The morphology of microbial cells was studied, and the biomass of microorganisms was estimated in the modern steppe soils and paleosols buried under kurgans in the Lower Volga region with the methods of electron microscopy. The shape and ultrastructure of the cells in the modern soils and paleosols were similar, though their average volumes differed (0.37 and 0.28 μm³, respectively). The portion of cells with a volume above 1 μm³ in the surface soils and paleosols reached 10.9 and 9.2%, respectively, and the portion of cells with a volume less than 0.01 μm³ in the surface soils was 10% lower than that in the buried paleosols. It was found that the cells of the microorganisms have an external organomineral layer, which increases the cell volume by 4.9 times, and this fact was taken into account in the calculation of the microbial biomass. In the chestnut and light chestnut paleosols, the latter comprised 1500 and 230 μg of C/g soil, respectively.     

Galapagos hydrothermal mounds: stratigraphy and chemistry revealed by deep-sea drilling

The Galápagos mounds sea-floor hydrothermal system is at least 300,000 years old and once produced manganese-poor sediments, which nearly blanketed the area of the present mounds field. Present-day mound deposits are limited manganese-rich exposures, suggesting that the system has changed from rock-to water-dominated and has diminished in intensity with time.     

Recent Soil-Forming Processes in Postagrogenic Soddy-Podzolic Soils of the Udmurt Republic

Eurasian Soil Science - We have revealed the dependence of current soil-forming processes in laylands on the period of theirs overgrowing, landform, and cultivation intensity. The main object of...     

Soils of Cryogenic Landforms in the South of the Vitim Plateau: Distribution and Role in the Allocation of Soil Carbon Pools

Eurasian Soil Science - The results of the study of cryogenic landforms (heave mounds and thermokarst depressions) and soils developed on them under conditions of the ultracontinental climate of...