In many cases feeding screw conveyors are missing in the fertilizer tanks of some double-row potato planters, as a result of which the lower layers of fertilizers left in the tanks, are fed manually. In order to exclude the manual work and to mechanize the process, as well as to eliminate compaction of loose fertilizer, we propose to install feeding screws with right and left turns. The design of the feeder should prevent the fertilizer compaction in the tank and ensure its constant mixing state or the so called “boiling” state. The working principles of the recommended metal rod feeding screw conveyor with round cross-section and the applied bladed screw conveyor are technologically different.

The article considers the effect of the diameter in the soil-tilling cutter with vertical rotation axis on the energy intensity of the technological process. By the analysis the approach of G.F. Popov has been approved according to which the dependence of the cutter's rotation moment (torque) on its diameter varies due to the regularities of the second-order curve. We believe that upon the constant cutter supply the growth of torque with increasing diameter is accounted for absolute knife speed, cutting force of the soil, as well as for the increase in the length of cutting trajectory. If the kinematic parameter of the rotary machine stays constant, then the increase in the thickness of cutting soil slice supplements the above mentioned reasons.

The article considers image processing methods, due to the application of which it becomes possible to continuously monitor the field conditions, identify weeds and to improve the crop quality. Design and prototype of the adjustable platform are introduced, which enable to implement various image processing algorithms depending on the application field. As compared to the microprocessor systems this platform makes it possible to integrate the system in one integrated circuit, which serves as an effective solution in terms of energy consumption and the occupied space.

When harvesting with potato digger the rate of potato separation is rather low, since the machine is overloaded with soil-tuber mass and soil clods. Thus, it is necessary to use an active rotor clod-crusher for the potato digger and in case of its precise speed selection the effectiveness of the potato digger will increase. It is recommended to increase the dynamic force in the strike of the working parts in the rotor clod-crusher up to the tubers’ safe separation. Per the results of calculations a diagram has been designed, which enables to make an optimal selection for the moving speed of the potato digger with secure tubers separation.

When designing new working parts for the tilling machine it is necessary to consider soil-working part interaction, as well as the issues related to soil deformation, decomposition and its transfer. Soil structure modeling will enable to get the optimal parameters of the working part in the tilling machine in three-dimensional space, its stress-strain state, to derive the traction resistance, as well as to calculate the strength of the working part.

The article considers some constructive developments of the grooved-roller sowing devices for the re-equipment of cereal crop seeding - machines. The recommended universal sowing unit enables to provide high sowing quality of the seeds of various crops, promotes seed saving, low cost price, as well as an increase in the annual loading of the device and a reduction in its exploitation costs. The article also indicates possible directions for further design improvements: increase in the universality level, improvement of sowing uniformity, stability of the sowing technological process regardless of the terrain relief, possibility of differentiated sowing with optimal parameters, etc.

Solution of travelling salesman problem (TSP) is very actual, since when implementing cargo transportation it is necessary to determine the possibly shortest (therefore, cost-efficient) route. The current article considers the study results of TSP Besides, algorithms applied for routing the agricultural cargo transportation, classification of the well-known methods and the most applied variants are introduced in the current work.

Investment environment is characterized as the integrity of social, economic, legal, political, cultural and geographical prerequisites whereby the investment feasibility is forecasted. An important component for its formation is the balanced macroeconomic state of the country. The attractiveness of the country's investment environment is indirectly evaluated based on a number of information sources. Besides, the investors can use independent information sources which describe the investment environment of a particular field.

One of the disadvantages of the clod crusher in the potato digger is insufficient crushing of the clods and the incomplete transfer of the crushed mass into the inter-bed space, as a result of which the clods mixed with the bed- border soil pass into the potato digger causing overloading. This exerts an adverse effect on tubers’ separation process and increases energy costs. It is recommended to increase the number of rotation in the working part of the clod crusher due to which the annual economic efficiency of the potato digger will make 808679.2 AMD.

Insurance of agricultural risks in different countries is carried out using different approaches, models, principles and basic indicators for assessing losses. They mostly depend on the development level of the country, diversity of statistical data, climatic features, etc. Currently it is recommended to introduce the model of production expenses in Armenia, thus, a necessity appears to find some justifications for the effectiveness of the mentioned model. The article considers negative and positive aspects of insurance model for production cost price and its productiveness in Armenia.

The life cycle development of “Polystigma rubrum” fungus has been investigated and the infection rate of different varieties of plums and cherry plums (myrobalan plum) with plum leaf blotch (Polystigmosis) has been identified. High infection rate has been registered in the cherry plum variety of Gogcha and plum variety of Persikovaya, while in the plum varieties of Renclod Green and Renclod Althan it was relatively lower. The experiments have shown that spraying with 3 % Bordeaux solution in the autumn season, as well as collection and elimination of plant residues after defoliation minimize the overwintering inoculum of the pathogen. The recommended triple spraying scheme (Score + Copper oxychloride2; Chorus + Taspa2) provides high biological efficiency reducing the disease by 92.6 %-96.4%.

The studies have been conducted in the non-irrigated conditions of the mid-mountain zones (Askeran region) at the Artsakh /NKR/ republic. In 2017-2018 the optimal dosage for the lentil sowing was determined through the accomplished trials. According to the research data resulted from the experimental variants with 110 kg/ha, 130 kg/ha, 150 kg/ha and 170 kg/ha sowing dosage and the control variant with 110 kg/ha sowing dosage, the lens-like lentil variety “Talin 6” with its utmost 150 kg/ha sowing dosage provides 10.3 c/ha yield. Thus, the mentioned variety is recommended to invest in the production.

In 2014-2016 the density of weediness in the sowings of winter, spring wheat and barley, as well as its dynamic changes were estimated in 8 various communities of the Shirak valley to determine the state of weediness as a result of which high rate of weediness was recorded. Since systemized soil cultivation doesn't result in the decrease of weed amount it is necessary to apply anti¬weed preparations.

The article considers the specifics of p-radiating radionuclides’ (RN) accumulation in vegetable (arugula, kale, lettuce, red Chinese cabbage, Chinese cabbage) and medicinal plants (lemon balm, breckland thyme, Saint John>s wort), cultivated in soil and hydroponic conditions at Ararat Valley (zone of ANPP at the radius of 30 km). It has been revealed that hydroponic plants are ecologically safer than soil plants. Thus, in order to get radio-ecologically safer raw material of plant origin biotechnological hydroponic production method is recommended. The total թ -radioactivity of vegetable and medicinal plants and the content of technogenic RN were within the range of permissible limits.

The results of diallel analysis of seven varieties of Samsun tobacco have been summed up in the second article of the presented series. The data testify that the green pigment content is largely affected by the impact of additive genes, which have demonstrated dominant characteristics in the high index varieties. Due to the positive high genetic correlations between the green pigment content and dry leaf yield, leaf formation rate and their number, the plant blossoming period and its height, the mentioned properties have been observed as a means of identification of perspective genotypes with high index of green pigment content in the elder hybrid generations. Specific pathways of selection optimization for aromatic varieties have been also recommended.

According to the researches the insecticidal bacteria of Bt species (BtECHs-68, BtECHs-73, BtECHs-92, Bt var. kurstaki) stay active for 3-4 months after spraying during the vegetation period with decreasing tendency in the forest brown soils. The decrease in the amount of insecticides has been promoted by individual soil-dwelling (hypo gene) bacteria species. It has been proved that the eponymous insecticides of Bt type incubated in the soil and not introduced in the soil actually demonstrate slightly-distinguished biological efficiency against the small caterpillars of winter moth.

The milk yielding capacity of the first- calf Holstein cows imported from Lithuania and kept in the specific cowsheds of the “Agroholding Armenia” LLC farm at the Lori region, RA, has made 6570 kg, the milk fat content - 4.2 %, protein - 3.32 %, live weight - 542 kg and the milk productivity coefficient - 12.1. According to the bonitization instructions the imported cows have considerably surpassed the standard indices of the Holstein breed, as well as their mothers bred in Lithuania in terms of milk productivity, fat and protein content, as well as in that of live weight. Thus, there is a feasibility for their further import and breeding.

In order to develop preventive measures against the cattle disease of monieziosis in Shirak and Vayots Dzor regions of Armenia soil and grass samples from the stock watering and resting sites have been taken. The studies of the samples were aimed at the disclosure of oribatid mites which are intermediate hosts for monieziosis pathogen. The latter are found in the soil and vegetation cover from the early spring, thus the epidemic culminates in summer fading away in the autumn months.

Epidemiological situation in the monkeys infected with pasteurellosis was investigated for the first time at Yerevan Zoo, Armenia. Climatic conditions of the zoo have contributed to the secondary pasteurellosis infection and local epidemic outbreak. Studies have shown that the infection propagates not only through infection carriers but also through infected water and food. Infectivity of pasteurellosis causative agents isolated from monkeys have been determined through biological methods on the white mice the mortality rate of which has made 83,3 %. Api 20 NE test has resulted in the detection of serotypes “A” and “D” and further propagation of infection has been prevented through special measures.

The aim of the research is to assess the risk of heavy metals in pasta products consumed by population of Yerevan. The content of heavy metals (Pb, Ni, Hg, Mo, Cd, Fe and Cu) was determined in the investigated pasta products. Estimated daily intake (EDI) and target hazard quotient (THQ) for heavy metals were calculated too. The results of the study have shown that the consumption of the investigated types of pasta does not pose health risks to Yerevan population.

The aim of this study is to assess the non-carcinogenic and carcinogenic risks of heavy metals (Cu, Fe, Mo, Ni, Pb, Cd, Hg) throughout the consumption of rice and buckwheat. Estimated Daily Intake of heavy metals (EDI), Target Hazard Quotient (THQ), and Carcinogenic Risk (CR) were estimated. According to the results, the daily intake of heavy metals and the consumption rate of rice and buckwheat do not exceed the established tolerable daily intakes. However, taking into consideration the consumption of the studied products, the chronic exposure of nickel can pose a carcinogenic risk.