International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The deficit of the irrigation water requires irrigation technologies of more efficient water use. For cucumbers the most suitable is the drip irrigation. For establish the appropriate irrigation schedule of cucumbers under the soil and climate conditions in the village of Chelopechene, near Sofia city, research was conducted with drip irrigation adopting varying irrigation schedules – from fully meeting the daily crops water requirements cucumbers to reduced depths with 20% and 40%. Have been established irrigation schedule, irrigation water productivity and yields of in plastic unheated greenhouses of the Sofia plant.

The paper presents a technical and economic background to the need for modernization of modern tractors and combines. The presented method allows forecasting the demand for modernization of equipment. It allows to develop the program of action to improve the quality of machines, assess their real potential, develop of strategic and operational planning for the development of modernization, organize activities of the technical service. This article proposes a method for determining the demand for modernization of agricultural machinery in technical, repair and technical enterprises, based on the analysis of statistical and expert data characterizing their influence on the demand for research. It is justified that repair company must confidently organize an active advertising campaign to promote modernized machines to the market.

Drip irrigation provides a fairly even mode of moisture in the soil and, along with this, favorable air, heat, microbiology and nutrition. As a result, there is an increase in yields and an improvement in the quality of production.
In order to determine the impact of drip irrigation, on the size of the yield and the economic indicators, in the cultivation of raspberries in the soil and meteorological conditions of the area of the village of Chelopechene – Sofia researches of an everbearing variety “Lyulin” were carried out. Various options have been tested – from fully satisfying the daily needs of the culture by water, irrigation with 20% and 40% irrigation norms to non- irrigating conditions.
The results obtained in years with different security of meteorological factors show that the drip irrigation of raspberries has a positive effect on the economic indicators of its cultivation, the costs of creating the raspberry crop, the irrigation system and the cultivation of the crop are redeemed for two or three years.

The increasing water deficit requires studies to optimize irrigation regimes and water-saving technologies to achieve economy of irrigation water at an acceptable yield level.
In order to establish the irrigation regime in the field of “Chelopechene” Experimental Field, Sofia, there have been researches, examining different regimes – from full satisfaction of the daily needs of culture for water to irrigation with reduced by 20% and 40% water application rates.
On average, over the survey period, the highest yields were obtained with the irrigated wit 100% water applicatipn rate. Reducing the irrigation rate leads to a corresponding reduction in yields and affects the quality of production. The application of regimes of irrigation with reduced iwater applicatipn rates is recommended  only in the case of water deficiency.

A Polish experience with 10 hybrids of sunflower field was made on the Chelopechene Field, Sofia, on cinnamon forest soil. Sunflower hybrids are grown under non-irrigating conditions and under irrigation conditions with drip irrigation and microwaving.

The meteorological conditions during the study period determined the number of irrigations and the size of the irrigation and irrigation norms of the culture.

It has been found that the yields obtained under irrigation conditions are higher than 13 to 46%, with drip irrigation giving better results than sprinkling.

The Maritsa, San Luka and A58xC23 hybrids have been shown to be suitable for growing in non-irrigated conditions, while the hybrids "Vokil", "Michaela" and "Maritsa" hybrids are irrigated.

To determine the irrigation water productivity for raspberries during their cultivation in the soil-meteorological conditions of the area of the village of Chelopechene – Sofia, studies have been carried out with drip irrigation of a plantation with the variety "Lyulin". Various regimes have been studied – from full satisfaction of the daily needs of the culture to water, to irrigation with 20% and 40% reduction in irrigation regulations.

The meteorological conditions during the study period determined the number of irrigations and the size of the irrigation and irrigation norms of the culture.

On average, over the survey period, the highest yields were obtained with the watered with 100% irrigation norm option. The increase in yields resulting from the irrigation is about three times the non-irrigated option in surface drip irrigation.

The highest irrigation water productivity of 4.3 kg of raspberries per cubic meter of water is obtained in variants irrigated with a 40% reduced irrigation rate.

The scientific problem of this study is the justification of the expediency of combining the technological operations of sowing cereals and applying the main and starting doses of mineral fertilizers when using a combined machine and tractor unit (aggregate). During the research there were used methods of conducting field experiments using standard equipment. During the planned experiments there were used correlation methods and methods of numerical calculations on a PC. The comparative studies of the quality of barley sowing with basic and modernized fertilizer-sowing units showed the following values of qualitative indicators. So, the coefficient of seed depth variation of the base unit was – 8.2%, and the combined (modernized) unit – 4.7%; The uniformity of seed distribution along the length of the line for the basic unit is – 63.8%, for the modernized unit – 84.9%; Field germination of seeds when sowing the basic unit is 80.4%, modernized – 87.4%. Thus, when using the combined fertilizer-seeding unit, the uniformity of seed distribution along the length of the string will be substantially increased. At the same time, the field germination of seeds will increase, and the coefficient of variation in the depth of seed placement in the furrow will decrease. Based on the results of field experimental studies, an increase in the yield of spring wheat and barley was found in the application of a combined fertilizer-seed aggregate with the simultaneous introduction of a basic fertilizer-seeded fertilizer into the soil and sowing of cereals with the application of a starting dose of mineral fertilizer in comparison with the known schemes of such operations. The obtained results confirm the expediency of combining these technological operations with one pass of the combined machine-tractor unit (aggregate).

The objective of the present study was to determine of effect of humic acid application and different foliar application of vermicompost extract and vermiwash on yield and yield components of safflower under using different levels of humic acid application in soil. A field experiment was conducted at the Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran. The experiment was conducted as factorial based on randomized complete block design. Treatments were included soil application of humic fertilizer (0, 500, 1000 and 1500 kg.ha^-1) and foliar spraying of vermiwash 1:10, vermiwash 1:20, compost tea and distilled a water as control. Seeds were hand-sewn with density of 40 plants m^-2 and a depth of 5 cm with row spacing of 50 cm. The plots were irrigated after 70 mm cumulative evaporation from standard evaporation pan class A and irrigation amount was based on soil moisture depletion. Seed yield and number of heads were determined by harvesting 10 plant at random from the four central rows at physiological maturity stage. Seed yield in each plot measured with 14% humidity. Number of seeds per heads was determined by measuring 30 heads at random from 10 randomized harvested plants. Analyses were performed with a personal computer using the MSTATC software. A factorial analysis of variance (ANOVA) was performed for all parameters. Results showed that humic fertilizer significantly affected head number, seed number, 1000 seed weight and seed yield of safflower, however there was no effect on branch number. The highest grain yield (5822.1 kg.ha^-1) obtained in 1500 kg humic. Foliar spraying significantly effect on branch number and the highest yield (4858 kg.ha^-1) was obtained by spraying of compost tea.

Rice, as the main food produced in Asia, requires more water than the other cereals. Flooded irrigation, the most common method of irrigation in rice, results high water losses and emits more greenhouse gases. Changes in climate, decrease in water resources and arable lands, necessitates the water productivity increasing strategies for rice. Soil matric potential based irrigation is such a strategy to irrigate rice under these conditions. This paper presents an experiment carried out inside a climate chamber to assess the water productivity of Bg300 rice variety using above approach. Three irrigation treatments; flooded treatment with a ponding water depth of 3cm and treatments with soil matric potentials at -150mbar and -300mbar were imposed in three large containers. Soil matric potentials were maintained using tensiometers installed at a depth of 20cm. Treatment at -150mbar showed best performance in terms of yield, water productivity and water savings. This strategy is transferable to a wide range of locations under different climates and reduces time for many field experiments.

The region of Varna proved to be a driest in terms of precipitation in this country. Trend test applied to climate datasets reviled a significant increase for seasonal reference evapotranspiration ETo during 1970-2004. Detected climate variability&droughts create uncertainties for maize irrigation scheduling and harvested yield. To cope with them, simulations have been performed for past (1951- 1984) and present (1951-2004) weather conditions using the validated water balance WinISAREG simulation model for two maize hybrids of different sensitivity to water stress grown on a Haplic Chernozem soil of medium water holding capacity. The study compares three irrigation scheduling alternatives built in agreement with past studies to develop environmentally sound/water saving irrigation technologies that consist of refilling the soil reservoir by adopting a management-allowed depletion fraction (MAD): (1) MAD=0.50; (2) MAD=0.33; (3) MAD=0.50 but partially refilling the soil reservoir. Simulations relative to the very high irrigation demand year of the current weather show that when aiming at maximum yield all three scheduling alternatives require the same irrigation depths ID=360mm that is 60 mm higher than conventional advised in the region. In the average demand years of past and current weather, Alternative 1 requires the same ID=270mm while a smaller ID=240mm is simulated with both alternatives 2 and 3 due to the fact that available soil water ASW is presently depleted to the optimum yield threshold OYT at harvest.

The aim of this study was to compare tillage methods and plant density on yield and yield components of soybean [Glycine max (L.) Merrill] grown under main and double cropping systems. The field experiments were carried out at the experimental area of Agricultural Faculty, Dicle University during 2013 and 2014. The experiments were conducted as split-split plot design based on randomized complete blocks with two sowing dates (normal and late) as the main plot, three tillage methods (no-tillage, reduced and conventional) as sub-plot, and three between row spacing (35, 55 and 70 cm) sub-sub plot factor. The experiments were performed in three replications and soybean cultivar Nova (MG III) was used. The combined analysis of the data showed that yield means of reduced tillage (2015.4 kg/ha) and conventional tillage (2036.1 kg ha^-1 ) were significantly different (P>0.01) compared with no-tillage (1881.1 kg/ha). Significant interaction was observed.
among experimental factors. The highest value was obtained at early sowing x conventional tillage x 70×5 cm as of 2206.1 kg ha^-1

After two years of research, the values of the controllable factors have been established that have a positive impact on the sowing quality of seeds of the French corn hybrids МАС47.Р and LG34.75. A correlation has been identified between the results of the laboratory and field studies after pre-sowing electromagnetic treatment of seeds of French corn hybrids. A good perspective for increasing the yield of corn grain is seen in the pre-sowing electromagnetic treatment of the seeds with the following controllable factors: voltage between the electrodes of the treating device U=1,65kV, duration of treatment τ=10s, and a rest of 14 days prior to sowing. Under the

described treatment, the obtained yield has increased by 22,5% compared to the reference specimen.