In the he article are presented the research result on effectiveness of application new form of urea on potato. New urea form is urea with urease inhibitors. This fertilities type allow to reduce losses of nitrogen in ammonium form. Field experiment was carried out in 2017 on solonetc light chestnut soils with heavy granulometric compound in the conditions of the Volgograd region in the experimental polygon of the lower Volga agricultural research Institute – branch of Federal state budgetary scientific institution "Federal scientific center for agro-ecology, integrated land reclamation and protective afforestation wounds". As an object of research used potatoes mid-early table varieties Nevsky. The advantage of a new fertilizer form is the yield increase and improvement of tubers quality. Urea UTEC application leads to formation bigger and uniform tuber size. The use of urea UTEC provide the potato yield of 56.4 t/ha, with marketable tubers fraction up to 54.82 t/ha, the total yield increase to the control – 35.6%, in monetary terms this amounted to 245887.0 RUB/ha additional profit. Under these conditions, was obtained lowest amount of non-marketable yield – 0.16 t/ha, which is 2.65 times less than in the control variant. The advantage of urea UTEC application in comparison with ammonium nitrate was the increase in the yield of marketable potatoes by 5.1 t/ha and an additional profit up to 76.8 thousand rubles/ha. The Assessment of the potato quality showed that the best treatment was also the treatment with UTEC urea, the starch content in tubers was 9.22%. Note that almost the same value of the indicator in the variant with the use of urea (option 2), and the lowest starch content was noted when using ammonium nitrate – 9.05%.

Relevance. Potatoes belong to crops that place high demands on the level of mineral nutrition. He needs nitrogen especially badly. Timely introduction of calculated doses of nitrogen fertilizers based on the results of photometric diagnostics of plants allows rational use of fertilizers and increase potato yields.Material and methods. The studies were carried out in the conditions of the Central region of the Non-Chernozem zone on sod-podzolic medium loamy soils with a high content of mobile forms of phosphorus and potassium and a low humus content (1,9%). The object of research is an early-ripening potato variety Bullfinch. To recalculate the dose of nitrogen fertilizing, photometric diagnostics of crops was carried out with an optical sensor GreenSeeker RT200. Additionally, before and after fertilizing, a manual N-tester Yara was examined. Before the main harvest, a control digging of tubers was carried out to determine the structure of the crop with division into 4 fractions.Results. It was found that the introduction of nitrogen fertilizers into the top dressing during the closing phase of the tops in the form of ammonium nitrate has a generally favorable effect on the growth and development of potatoes. This is confirmed by the results of photometric diagnostics performed by the Yara N-tester during the withering phase of the tops. When applying top dressing with a fixed dose, the N-tester readings were 21,7% higher than in the control, and when applying fertilizers with a differentiated dose by 25,6%. The yield of potato tubers increased when applying a fixed dose of top dressing by 10,8%, differentiated by 14,5% compared to the control.

Relevance. One of the most common diseases of potatoes and other nightshade family species is late blight caused by a pathogenic oomycete of the Phytophthora infestans (Mont.) de Bary. At least 100 species of phytophthora have been described in nature, affecting a wide range of plant species. The phytophthora population is heterogeneous and is represented by races, as well as different types of mating. This leads to a rapid adaptation of the pathogen and the emergence of new, more aggressive, and resistant races. Phytophthora is a parasite, the damage from which cannot be avoided within the organic farming framework. Therefore, it is particularly important to know the pathogenesis and racial composition of phytophthora in each individual region of Solanaceae cultivation.Research methodology. Differentiation and collection of material from the natural population were carried out using potato varieties with known R-genes in the genome. Isolation and introduction into the culture were carried out from leaves with the dampening chambers method, followed by cultivation on nutrient media. The pathogen was identified by microscopic analysis. Culture filtrates were obtained on the liquid nutritious medium, followed by liquid filtration and autoclaving. Phytotoxic activity was determined by the effect on the seedlings of the nightshade, grass, and pea families by the standard method. Molecular genetic analysis of the isolates was carried out by ISSR analysis; the primer, amplification mixture, and temperature profile of the reaction were selected according to the literature data; the calculation of genetic characteristics was carried out using POPGENE software packages.Results. Samples of seven Phytophthora infestans isolates were collected and introduced into culture. As a result of in vitro cultivation, morphological differences were revealed, expressed in the structure and color of the mycelium, the shape of the colonies, the nature of sporulation, the color of the reverse, and the medium under the colonies. The genetic differences of the natural phytophthora material introduced into the culture, collected from potato varieties with single resistance genes (R1, R3, R4), were revealed. Differences in the phytotoxic activity of the studied isolates' cultural filtrates were revealed. The isolated isolates demonstrate differentiation at the phenotypic, genetic and physiological levels, which allows us to speak about their belonging to races.

Relevance and research material. In 2023, it was 100 years since the beginning of the collection, study and preservation of the world doublet collection of potatoes (UNU, registration USU_505851) at the Polar Experimental Station of the VIR branch. This is one of the oldest and unique potato collections, the preservation of which is carried out in the field. The first potato samples began to enter the collection in 1923. Now the potato doublet collection has 3200 samples. It includes breeding varieties, hybrids, cultivated South American potato species Solanum andigenum Juz. et Buk, Solanum chilotanum Hawkes.Results. The collection is a unique genetic material that is of high importance in solving issues of improving the efficiency of agriculture in the country. As part of the field collection of potatoes, the source material for dangerous quarantine objects is quite widely presented: potato cancer (Synchytrium endobioticum (Schilb.) Persiva) and globoderosis (Globodera rostochiensis Woll.). There are donors of late blight resistance (Phytophthora infestans (Mont.) de Bary.). There is a source material in the collection that has economically valuable characteristics: precocity, frost resistance, yield, marketability. Varieties with a high amount of phenolic compounds in the tuber pulp are also included in the field doublet collection. Such varieties are suitable for dietary nutrition and can be used in the prevention of a number of diseases.Conclusion. The collection of the collection is of great importance for applied research and for ensuring food security of the region and the country as a whole.

Methodology. The purpose of the research: to study the yield and quality of tubers of early ripe potato varieties Charoit and Meteor in organic farming in the northern forest-steppe of the Tyumen region. Studies were carried out in 2019- 2022 on the experimental field of the Northern Trans-Ural State Agricultural University. The soil of chernozem is leached, heavily carbonaceous in grain size distribution, medium provided with nitrogen and phosphorus, good – potassium, pH – 6.7 humus content – 7.2%. The content of trace elements in the soil is satisfactory. The precursor is spring wheat + rape per siderate. The green mass of the sideral culture (170 c/ha) was smelled on the fifth of October. In the spring, harrowing was carried out in order to retain moisture in the soil, then at a temperature of + 10…+12°C at a depth of 10-12 cm, milling, cutting of ridges and planting with sprouted tubers were carried out. The landing scheme is 75x30 cm, the plot area is 50 m2, the accounting one is 30 m2, the repetition is four times, the location of the plots is rendered. Prior to planting, tubers were treated with Taboo, 1 L/t and growth bioregulator Rostock, 0.5 L/t, and plants were treated with Immunocytophyte, 0.5 g/ha during the budding phase. Mineral fertilizers were not contributed. Caring for potato plantings included two interrow treatments and sinking.Results. It was established that in potato crop rotation with the annual use of sideral fertilizers, the yield of the noted varieties averaged 21.7-22.0 t/ha over four years, or 1.1-1.4 t/ha higher than the Zhukovsky early standard. The yield was combined with high quality tubers: starch content 13.9-14.6%, vitamin "C" 15.6-16.4 mg/%, nitrates – 59-81 mg/100 g, taste rating – 4.1-4.3 points.

Relevance. The use of non-invasive photometric methods for assessing the stress states of plants makes it possible to assess the physiological state and resistance of plants.Material and methods. In small-field and vegetation experiments, we studied the photometric indicators of the physiological response of potato varieties (reflection coefficients in different ranges) to nitrogen stress created by five doses of fertilizers using contact (N-tester) and remote (N-sensor) methods.Results. Potato varieties released for the conditions of the North-Western region of the Russian Federation were studied for their ability to withstand stress provided by low and high levels of nitrogen nutrition of plants and different weights of planting tubers. The resistance of plants of different genotypes to external and internal stressors was studied by the reflection coefficients measured in 4 channels, which characterized the differences in the physiological state of plants. Ensuring the potential genotypic resistance of the organism in the form of a decrease in FIS F1,3 corresponds to the inclusion of various mechanisms of plant adaptation to external or internal influences, depending on the genotype. In the vegetative experiment, of the studied photo-optical reflection coefficients, the most informative were the FIS F1,3 indicators, which showed that the overall viability of such varieties as Peterburgsky, Charodey and Kholmogorsky turned out to be increased. The reaction type of the Kholmogorsky variety is the most promising for growing plants under stress conditions.

Relevance For the successful introduction of a new variety of potatoes into production, it is important to know the technological parameters of its cultivation, both for seed and food purposes. Methods Studies on the timing, planting schemes and doses of mineral fertilizers, providing maximum yield of seed and food tubers of a new potato variety Smolyanochka breeding Smolensk GOSHOS, were conducted in 2017-2018. Experience, observations and accounting were carried out according to generally accepted methods. The studies were conducted in the field short-term experience of the Smolensk Institute of agriculture (ex. Smolensk GOSHOS) on sod-podzolic medium-loamy soil with low humus content, weak acid reaction of the soil environment, high content of mobile phosphorus and high potassium content. Results Observations of the growth and development of potato plants of the Smolyanochka variety showed that the length of the growing season decreased from early planting to later. Planting schemes and fertilizer doses did not have a significant impact on the duration of development phases in all variants of the experiment. The density of the stem per unit area decreased by 5-18% from earlier planting dates to later and increased with an increase in the dose of mineral fertilizers to N60P72K90 by 12-28%, compared with the background of N32P32K32. The highest percentage of plant viral diseases during the growing season was observed with a more thickened planting scheme (70x25 cm) and increased with later planting dates. The maximum yield of potato tubers when grown for both seed and food purposes was noted against the background of mineral fertilizers at a dose of N60P72K90 when planted earlier. Post-harvest tuberous analysis of potatoes showed that all the studied variants of the experiment did not have a significant impact on the affection of potato tubers with fungal diseases.

The article presents the results of a study of varieties collection of different ecological-geographic origin on light-brown soils in the summer planting and watering irrigation. The promising, high-yielding varieties for cultivation in the Astrakhan region were selected.

The developed technology, regulatory and technical documentation allowed to produce 3-5-kg packages of sterilized vegetables: potatoes, beets, carrots and cabbage, which are in great demand in the social nutrition (the army, schools, hospitals). The use of packaging for products of composite materials allows to reduce the amount of required storage space.