Vol 9, No 2 (2024)

The purpose of the research is to increase the productivity of pear cultivars after overwintering in low–temperature conditions. The initial forms and results of breeding work on winter hardiness and productivity of pears in Research Institute «Zhigulevskie Sady» and other research institutions were analyzed. The winterkill of fruit buds in the winter of 2022-2023 was studied in pear cultivars and the grouping of cultivars by winter hardiness was carried out. Highly winter resistant cultivars of their own breeding such as Muskatka, Darenka, Kristina, Samaryanka, Zhigulinka, Volzhanka, Zvezdochka have been identified. According to the yield and the complex of economically valuable signs, the cultivars Darenka, Marshal Zhukov, Chizhovskaya, Samaryanka, Skromnitsa, Pamyati Yakovleva, Muskatka, Bergamot Samarskii, Pamyat Zhegalova, Samarskaya Zhemchuzhina stood out. From the studied pear cultivars, the following varieties were selected as initial forms for further breeding work Darenka, Yakhontovaya, Marshal Zhukov, Samarskaya zhemchuzhina, Pamyati Yakovleva, Chizhovskaya and elites Smuglyanka, Zvezdochka, Assol, Nadezhda, Volzhanka. Muskatka and Bergamot Samarskii varieties are recommended for transfer to the state variety testing.

Scientific research presents data on the study of the effect of pre-planting tubers division by specific gravity with simultaneous treatment in a solution of mineral fertilizers on disease infection and potato keeping in the Ryazan district of the Ryazan region. The object of research was the medium-ripened variety of food potatoes Favorit. Agrotechnical measures for potato cultivation are generally accepted for the zone. The studies were carried out according to the method of tuber selection by specific gravity in a solution of mineral fertilizers with the concentration established depending on the starch content in them. Each variant was stored in synthetic nets during harvesting. Before storage, the lowest tuber disease incidence was in the variant with tubers of the highest density and averaged 15.9% over three years, and 27.6% in the control. After seven months of storage, the lowest percentage of diseased tubers was observed in the variant with high–starch tubers and was 19.3% versus 38.2% in the control, and the highest in the variant with low-starch tubers – 40.2%. The amount of starch in the tubers after storage decreased in all variants and amounted to an average of 10.5 to 12.3% over three years. The starch yield per hectare in the variant with highly starchy tubers was 38.56 c, and in the control 31.46 c. The absolute waste in the control and the variant with low-starchy tubers was higher than the other variants of the experiment and amounted to 10.0 and 10.7% respectively, and lower in the variant with high–starchy tubers – 7.0%. It has been established that the application of the tuber density selection method makes it possible to significantly improve seed potatoes and reduce the overall percentage of diseases after seven months of storage.

The purpose of the research is to perform an experimental assessment of the wear characteristics of plunger pairs of an inline four–section high–pressure fuel pump (injection pump) HPFP based on the results of non-motorized comparative accelerated tests with simultaneous operation of two pumping sections on petroleum diesel fuel and two others on bio-oil fuel, the vegetable component of which is rapeseed oil. Today, one of the global problems of mankind is the decarbonization of energy. An important vector of development to achieve carbon neutrality is the reduction of harmful emissions from motor vehicles generated by the combustion of motor fuels in internal combustion engines through the use of alternative fuels from renewable sources of raw materials with a small "carbon footprint". A promising direction in the production of alternative diesel fuels from renewable biomass is considered to be bio-oil fuel (BOF), the components of which are natural vegetable oil and commercial petroleum diesel fuel (PDF) in a certain ratio. In modern conditions of the transition of motor vehicles diesel engines operations from traditional types of motor fuels to alternative fuels, it becomes necessary to conduct experimental studies to assess the effect of BOF on the wear of plunger pairs of high-pressure fuel pumps (injection pumps) HPFP, as the main unit of diesel fuel equipment. The obtained results of accelerated wear tests of plunger pairs of a four–section injection pump on a non-motorized stand with simultaneous operation of two of its sections on PDF and two others on rapeseed BOF, indicate that when the injection pump(HPFP) is running on BOF, wear indicators are lower compared to operation on commercial PDF.

The purpose of the research is to evaluate the constructive and kinematic parameters of the mechanism of regulation of the working parts of a combined cultivator from the operating conditions, which provides the necessary impact on the object of processing – the soil. Modern problems of the agro-industrial complex pose to scientists the creation of new tillage machines based on the use of achievements in the field of information and switching, geoinformation and computer technologies that can increase productivity, reduce energy and labor costs in obtaining agricultural products. There is an urgent need to develop combined cultivators capable of forming a seedbed in one pass in accordance with agrotechnical requirements, as well as with the possibility of changing technological parameters depending on the state of the soil and the biological characteristics of the cultivated crop. We have proposed the design of an adaptive combined cultivator with a mechanism for regulating the stiffness of the roller suspension and determined the theoretical dependencies characterizing its design and operating parameters based on the provisions of classical mechanics and the laws of mathematics. The required force of the spring control mechanism has been determined to ensure the required roller pressure. From the equilibrium condition of the roller, taking into account the impact of forces and moments from the soil on the roller, its parameters are determined, which ensure its operability. The conducted experimental studies have shown that in the range of working depth of cultivation and soil density, the indicator of soil quality is within the limits of agrotechnical requirements and amounts to 83...89%. Therefore, in order to improve the quality of processing, it is necessary to use adaptive combined machines and units capable of adapting to any soil conditions.

The aim of the research was to substantiate the use of the drug «Immunopharm» to stimulate metabolic processes in highly productive cows after prolonged lactation in order to prevent the manifestation of generic subclinical mastitis. In order to conduct research, we selected 40 heads of cows based on similarity, which were then divided into four groups of 10 animals each (control, experimental-1, experimental-2, experimental-3). «Immunopharm» was initiated in experimental groups of cows 30-35 days after the start of dry cows three times every seven days and twice after calving after 48 hours with a gap of 12 hours (experimental first group – 4.0 ml; experimental second group – 6.0 ml; experimental third group – 8.0 ml). The Immunopharm preparation was not injected into the control group of cows. During the experiment, all cows were kept and fed in the same way. Based on the conducted scientific experiment, a conclusion was made about the positive effect of the preparation «Immunopharm» on the level of metabolism in cows. The use of this preparation at a dose of 6.0 ml intramuscularly three times with an interval of 7 days after running period, carried out in cows of the second experimental group, gave the following changes in blood plasma parameters on the 10th day after calving compared with the control group: an increase in the content of immunoglobulin G in the blood plasma of cows by 87.32 units / l, total protein by 7.02 g/l, α-globulins by 2.89%, increase in glucose concentration by 0.57 mmol/L, total calcium by 0.39 mmol/L, alkaline reserve content by 2.94%, decrease in β-globulins by 1.74, the level of total bilirubin by 4.22 mmol/l, the level of the enzyme AlAT by 10.58 units / l, the level of the enzyme AsAT by 16.9 units / l. Milk quality indicators also showed improvements: the protein and fat content exceeded the gradients of the control group. However, the high level of somatic cells in animals of the control group indicates the presence of an inflammatory process in the mammary gland. This is confirmed by the results of milk research in both cows of the control group and in individuals of the first experimental group, which is confirmed by the results of milk research in cows of the control and experimental first groups.

The article considers the possibility of increasing and improving both quantitative and qualitative indicators of dairy productivity of cows with full, balanced feeding. The purpose of the research is to increase the milk productivity of cows of the created Bashkir type of black–and-white breed introducing the premix «Megamix-Optilak» into the feeding diet. The object of research is lactating cows of a black-and-white breed of the Bashkir type. To conduct the research on the principle of analogues, taking into account origin, live weight, milk productivity, age in lactation, and physiological condition, we selected 80 animals divided into 4 groups of cows with 20 heads each. The research was conducted on the basis of the farm of Chekmagushevsky district of the Republic of Bashkortostan. Standard research methods were used in the work. The research results demonstrate a positive trend from the use of the studied premix. In particular, a significant increase in the average daily milk yield and dairy productivity of cows over the entire lactation period was established. At the same time, the fat content of cows in the experimental groups averaged 3.89%. We also noted a positive change in the quality indicators of the milk obtained: the fat content of milk was 3.89%; the lactose content was 4.94%, and the protein yield increased by 14.06%. The studies have shown that the introduction of the Megamix-Optilak premix into the feed rations of lactating cows has a beneficial effect on the quantitative and qualitative indicators of dairy productivity of animals. The rich vitamin and mineral composition of the studied premix promotes the digestibility of feed, strengthens the immune system of animals. The best indicators of milk productivity were established in the group of cows receiving the premix «Megamix-Optilak» as part of the diet at a dose of 200 g/head per day.