Annals of Agrarian Science最新文献

Soil is a dynamic system in which relationship among soil minerals, organic substances and living organisms constantly exists. Microflora is an integral part of complex system of soil in which bacteria are the largest group of soil microbes, both by total number and diversity. The study of bacterial composition of 18 types of soils from Western, Eastern and Southern Georgia has shown that soils are distinguished both by total number of bacteria and by frequency of occurrence for certain investigated bacterial genera (Bacillus, Pseudomonas, Rhodococcus). Bog (7.87 Log10 CFU/g) and brown forest (7.22 Log10 CFU/g) soils of Western Georgia, black (8.80 Log10 CFU/g) and grey cinnamonic (7.91Log10 CFU/g) soils of Eastern Georgia and Chernozem (10.92 Log10 CFU/g) of Souther Georgia are the richest by total number of bacteria. Bacteria of the genus Bacillus prevailed in most of studied soils (yellow, bog, yellow podzols, mountain meadow, saline, meadow cinnamonic, cinnamonic, mountain forest meadow, mountain meadow, meadow grey cinnamonic, grey cinnamonic, chernozem, brown forest black, raw carbonate soil in Western Georgia and brown forest in soil of Southern Georgia); bacteria of the genus Pseudomonas – in alluvial and brown forest soils both of Western and Eastern Georgia, and bacteria of the genus Rhodococcus – in yellow brown forest, red and Raw carbonate soil of Eastern Georgia. All three groups of bacteria occur at the same frequency only in black soil.

The work offers a mathematical model of interaction of the tractor driving wheels with the soil. A rheological model is used as a law of shear deformation of soils as the principal law of linear deformation. Calculation formulae of tangential force and traction coefficient of the driving wheels are deduced. A numerical example and graphs are used to demonstrate that the theoretical results are quite close to the experimental data. Dependence of the traction coefficient of the deformable wheel with the ground allows analyzing the impact of rheological indicators of grounds and geometric and regime parameter of a wheel rolling and using a more grounded approach to the analysis of the problematic issues of dynamics of wheeled tractors. As it can be seen from formulae the tangential traction force and traction coefficient of an elastic wheel necessary to overcome the forces of friction, shear and ground cutting depend on normal load mg, acting on the wheel, wheel parameters rheological properties of the ground and movement regime.

Action and aftereffect of the herbicides with different modes of action on the common ragweed population were studied in the field and greenhouse experiments. Activation of glutathione S-transferase has been detected due to the action of herbicides Harness and Guardian-Tetra both in leaves of juvenile plants and in ragweed seeds, which indicates intensive detoxification of herbicides during weed ontogenesis. Electrophoretic analysis showed that four components in protein spectra of ragweed seeds were inherent in seeds collected from herbicides-treated plants only. Using the method of isoelectric focusing, three specific peroxidase isoforms associated with a certain mechanism of herbicidal action on the parent plants were found in leaves of the next generation plants. The results confirm the intensive adaptive changes in A. artemisiifolia population that could provide the metabolic resistance to different modes of the herbicide action.

Heteronuclear chelate citrates of the general formula M₂^I·M^II·L₂·nH₂O (where M^I and M^II = Mn, Zn, Fe, Co,Cu) have been synthesized. Premixes prepared on their basis were tested in nutrition of layer and broiler poultry. On the basis of experimental data we calculated economic efficacy of egg-laying for layers within 60 days from starting intense egg-laying. Economic efficiency of poultry rearing, for broilers, was calculated from the 7th day after hatching till the 35th day. Computations for broilers were made per 1000 broiler, while for layers – per 20 hens. In both cases four groups were used: I – control, when feed was balanced with the premix used generally at the factory; II group, experimental – with the premix that contained minimal doze of chelate citrates; III group, experimental – with premixes containing normal doze of chelate citrates and the IV group, experimental – with premix containing maximal dose of chelate citrates.

On the basis of the experiment results we can conclude that in all (three) experimental groups where the premixes were balanced with the synthesized chelate citrates, the profit, compared to the control group, was higher, while the highest profit was obtained from the group which was given feed with the premix balanced with maximum dose of chelates.

We have carried out physical and chemical study of heteronuclear citrates. Solubility of these citrates was investigated in various solvents. It was determined that these citrates are characterized by poor solubility in all solvents, both at room temperature and when heating.

To determine the nature of citrate ion deprotonation and linking with metals in the M₂^I·M^II·L₂·nH₂O type chelate compounds, we made and studied their IR absorption spectra, according to which, the synthesized compounds are the internal type chelate compounds and as it was expected, all three deprotonated carboxylic groups of citrate acid form both ionic and coordination bounds with metal atoms.

The aspiration of launching urban community gardens is spreading in Central Eastern Europe (CEE). The joy of common work and spending meaningful time in well-designed gardens could bridge the gap between local community members. At the same time, this is how common understanding and social responsibility can be established. The aim of this paper is to compare existing practices of urban gardening in the Central and Eastern European region and investigate their opportunities and limitations. Five capital cities (Budapest, Bratislava, Prague, Warsaw and Zagreb) were chosen for this research with benchmark method to analyse aims, main motivation and end-user beneficiary from urban gardens.