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In the article the state of the art and the main tendencies of cloud computing development are analyzed. The importance of cloud technologies application in education is grounded. The directions of their appliance are examined in higher education, in particular as for the creation of the cloud-oriented learning scientific environment at educational institutions. The advantages of transfer of IT-infrastructure of higher educational institutions into the cloud form are shown (the economy of funds for purchase of software and renovation of computer database; the reduction of the need for specially equipped premises; the creation of an open educational environment). The main directions of the research study of cloud technologies application in the process of professional training of programmers are characterized, among them there are: 1) formation of skills of the cloud services use for the professional tasks solving; 2) formation of skills of the development of cloud applications, deployment of cloud infrastructure, cloud applications and data bases security support. The description of cloud services that can be used in the process of programming learning and usage of training projects (Ideone, Codenvy, DbDesigner) are provided. The brief description of the possibilities of the Amazon platform usage for formation of cloud software development skills is provided.

Maintaining and increasing the stock of soil organic carbon is of vital importance in maintaining the soil fertility. In present research the changes in the content of organic carbon (SOC) and total nitrogen (Ntot) in the soil are investigated. The data is collected from the long-term field experiment, which compares organic and conventional farming systems in a crop rotation (barley undersown with red clover, red clover, winter wheat, pea, potato) during 2014-2018. Based on the 5-year experiment, it was concluded that the cropping systems have a significant effect on the SOC content and a smaller effect on the Ntot content of the soil. The diversification of organic cropping systems with cover crops and composted cattle manure significantly increases the content of organic carbon in the soil. The results of the experiment indicate that the content of organic carbon was significantly lower (by 7.6-12.6%) in conventional systems, where pesticides had been applied and cover crops and manure had not been used, compared to the organic cropping systems. The correlations between the SOC contents of main crops and precrops were statistically more significant in organic farming system, compared to the conventional system. Highest SOC and Ntot values were observed in organic systems with cover crops and composted manure fertilization. Hence, it can be stated that in order to improve the soil fertility and fix more carbon and nitrogen, high amounts of organic material should be applied into the soil and the activity of soil microbes should be a priority. The organic cropping systems have more advantages for sustainable crop production. [ABSTRACT FROM AUTHOR]

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Rhizoctonia disease in potato is widely distributed in Estonia. Field experiments with cv. 'Red Fantasy' were undertaken with seven pre-crop treatments at the Estonian Research Institute of Agriculture in 2009 and 2010. Monocropped potato, spring barley, spring barley underseeded with red clover, spring wheat, grain pea, spring oil seed rape and oil seed radish were involved in the study as pre-crops. Growing conditions on both years were rather optimal for potato growth but year 2010 was drier at early bulking stage. The effect of different pre-crops on Rhizoctonia solani complex was studied (i.e. incidence and severity of stem and stolon canker and black scurf) at 15, 30, 45, 60, 90 and 120 days after planting. Results indicated that pathogenfree seed tubers are of primary importance in the disease control and no pre-crop was suppressive to disease if seed tubers had sufficient amount of inoculum. However, to achieve consistent reduction in disease development, inoculum-free seed tubers and crop rotation with non-host crops should be considered. [ABSTRACT FROM AUTHOR]

In 2008 an experiment was set up on the field in Eerika experimental station (Estonian University of Life Sciences) as a 5-field crop rotation: red clover, winter wheat, pea, potato and barley undersown with red clover. The objective of the study was to measure the content of weed seeds in the soil and to evaluate the diversity of the species at the end of the period of converting to organic production. In conventional farming systems without fertilizer (Conv I) and conventional farming with mineral fertilizer (Conv II) herbicides were used for weed control. All the crops in Conv II system received P 25 kg ha-1 and K 95 kg ha-1, but the application rates of mineral nitrogen fertilizer differed. In organic systems (Org I - organic farming based on winter cover crop and Org II - organic farming based on winter cover crop and manure), the winter cover crops (ryegrass after winter wheat, winter oilseed rape after pea, winter rye after potato) were sown after the harvest and were ploughed into the soil as green manure in spring. The content of annual weed seeds was the lowest in red clover that had 17.7% less weed seeds in the soil of Org II system compared to control (Conv I). In winter wheat the content of winter annual weed seeds was 50-76% higher compared to other crops. By the end of 2009 the content of organic carbon (Corg %) in the soil had increased significantly in both organic systems which results in higher activity of organisms that decrease the viability of weed seeds. [ABSTRACT FROM AUTHOR]