The research results of the assessment of potatoes varieties by a set of economically valuable traits in the conditions of western region of the Republic of Belarus are presented. Varieties were characterized and distinguished by productivity, starchiness, adaptability coefficient, resistance to the most common pathogens and the taste qualities of the studied varieties were evaluated.
As a research result, it was found that for cultivation in the conditions of the western region of Belarus for food purposes it is possible to recommend early ripe varieties Colomba (the Netherlands), Ovation (Poland); medium early varieties Mastak (Belarus), Typhoon (Poland); medium ripe Guarantee (Belarus); medium late variety Rubin (Belarus).

The analysis of the main economically valuable traits of potatoes varieties Lazar and Hozyayushka created in Omsk Agrarian Scientific Center (Omsk ASC), in various soil and climatic conditions is presented. In addition to high biochemical parameters for dry matter and starch content, protein, vitamin C, they have a low content of reducing sugars, high productivity, resistance to diseases, etc. Varieties are used in various breeding programs to improve the quality of tubers and increase percentage of hybrids selection with complex valuable traits.

The new varieties of potatoes breeding of RUE «Scientific and Practical Center of NAS of Belarus for Potato, Fruit and Vegetable Growing» are described in the article.

The research results on productivity of parental forms are presented, variation of the index in hybrid offspring is studied, hybrids exceeding the best of parental forms in productivity, as well as having 1000 and more g/bush are isolated. Compared to varieties, higher productivity is observed in interspecific hybrids. The maximum value of productivity limits was found in six populations involving interspecific hybrids and only in two – intervariental hybrids. The highest average productivity was shown by the offspring of the combination of Bagryan variety crossing and interspecific hybrid 89.202c79 – 784 g/bush, which is 2.32 times increases the value of the best standards. Almost in every population, hybrids with productivity exceeding the best parental form were released, and in eight populations, hybrids with productivity of 1000 or more g/bush were released.

As a result of the analysis of the content of macro- and micro-components in tubers of collectible varieties of potatoes, a wide variability of biochemical composition indicators depending on their genotypic features and growing conditions was revealed. A significant excess of the average content of the majority of macro- and micro-components in tubers was observed in the middle early variety Svitanok Kievskiy, middleripe Granola and Saturnа, as well as middlelate Picasso and Nakra. Effective use of these varieties as parent forms in selection to increase the content of macro- and micro-components in the tubers of hybrid offspring will allow targeted selection of new promising varieties with increased tubers nutritional quality.

In 2105 samples of potatoes tubers with yellow, red, purple skin and white, cream, yellow, red and purple flesh of various breeding nurseries, the total antioxidant capacity (TAC) was determined by photoluminescence. It was found that the greatest TAC have potatoes tubers with purple skin and flesh, followed by tubers with red and pink skin and flesh. Among tubers with white, cream and yellow flesh, TAC are higher in samples with purple rind, followed by samples with red rind and yellow. It was found that potatoes with yellow skin, TAC higher tubers with yellow and cream flesh, compared with white. Tubers with yellow and cream pulp do not differ in TAC. Differences in TAC between samples with yellow, white, cream pulp and purple and red peel are not proven. Changes in TAC of tubers by 36.0 % are associated with the color of the tuber flesh and by 23.1 % with the peel color. The share of influence of other signs on the studied indicator is 40.9 %.

The results of PCR-identification of extra resistance genes to PVY (Ry_adg, Ry_sto, Ry-f_sto, Rу_chc) between complex interspecific potatoes hybrids and discriminating from that initial material genotypes with immunity to virus are presented in the article. The gained data testify the possibility of combination in one genotype of genes from different gene sources. Assigned potatoes genotypes can be utilized in breeding gene sources of different genes of extra resistance to Y-virus.

Complex interspecific hybrids with potential for use in breeding for late blight resistance have been obtained by involvement in the breeding process of somatic hybrids produced on the basis of wild potatoes species: S. bulbocastanum, S. polyadenium, S. etuberosum. The hybrids 42-13-20, 147-09-9, 155-13-29 and 50-12-2 are recommended as the initial forms in breeding program for complex resistance to late blight.

As a result of a two-year assessment of the damage to potatoes tubers during the storage of 10 varieties, it turned out that the varieties of Monte-Carlo, Labella, Marlene, Bellarose, Barvina and Soraya were the most affected (5–7 % of the total tubers were damaged), and the least affected were Carrera, Wendy, Toskana, Belmondo (0.5– 3.5 %). The lowest crop losses (0.2–1.9 %) were on the Wendy, Toscana varieties with low tuber lesion rates and the largest (13.0–18.9 %) were on the varieties with the highest percentage of the large-fruit tuber-affected Soraya, Barvina, Labella varieties. Phytoparasitic nematodes were found in tubers but saprobiotic species were present: Panagrolaimus rigidus, Eucephalobus mucronatus, Caenorhabditis elegans. Fusarium spp. fngi were found on tubers of varieties of Barvina, Soraya, Monte-Carlo, Labella, Belmondo and Bellarose. Alternaria spp. fungi were found only on the potatoes tubers of Soraya and Marlene varieties. We found no nematodes or fungi on Carrera, Wendy and Toscana varieties.

The research results of the prevalence and populations structure of potatoes viral diseases in Brest region are presented. It was established that a relatively favorable virological situation in potatoes plantings was developed in Ivanovo district. The most affected potatoes plantings with a viral infection were detected in Lyahovichi and Pruzhany districts.

Ecological aspects of microorganisms use in technologies of potatoes and vegetable crops cultivation for effective control of pests and plant pathogens were shown. The results of effectiveness evaluation of biological preparation Xantrel, intended to protect potatoes and vegetable crops from pests and diseases are presented.

The research results of the aggressive and virulent properties of the pathogen of watery wound rot of potatoes Pythiym ultimum Trow for the period 2017–2018 are given.

The two-year data on resistance of competitive variety trials of potatoes hybrids to Rhizoctonia solani Kuhn. are presented in the article. The estimation of potatoes breeding material for sprouts and tubers for resistance to Rhizoctonia solani Kuhn. is given and some hybrids are recommended for breeding process.

The research results on the authenticity of detection of PVS in an integrated sample by ELISA are presented in the article. It is shown that one infected plant in a combined sample is sufficient to detect PVS.

The results of fresh and frozen leaf material use to obtain preparative amounts of PVX are given in the article. It was established that the use of fresh leaves for the isolation of potatoes virus X provides a high yield of the viral preparation (more than 162 mg out of 1000 g of leaves), leaf freezing at –18 °C before virus isolation leads to a decrease in the yield of the viral preparation.

The economic efficiency of growing food potatoes depending on the row spacing (70 and 90 cm), methods of pre-planting (plowing, soil dredging) and subsequent soil treatments (planting care during the growing season) is presented in the article.

The reserch results of the influence of pre-planting methods of sod-podzolic medium sandy loam soil on agrophysical soil indicators, yield, as well as biometric, biochemical indicators of studied potatoes varieties are presented in the article. The economic efficiency of growing food potatoes is calculated depending on the studied agricultural plans.

The main requirements to be met by the systems of identification and inspection of nonconforming potatoes tubers are considered. The methodology for creating a database of nonconforming potatoes tubers is proposed in the article. The analysis of their external defects is given.

The presented researches designated the possibility of efficiency increase of potatoes and efficiency use of nutrients from mineral fertilizers. Reaction of varieties of various groups of ripeness to introduction of mineral fertilizers at the changing density of potatoes landing is shown.
The increase in planting density led to an increase in potatoes yield up to 18 %. The use of maximum doses of mineral fertilizers contributed to the marketability increase of potatoes tubers by 2–13 %. It was found that the use of fertilizers dose N₁₂₀P₆₀K₁₈₀ contributed to obtaining the highest rate of return on investment, profitability and productivity.

The traits of the connection of potatoes seed tubers mass formed within the clone, with the elements of yield structure of plants which were in the stage of forming are discussed in the article. It was determined that the planting tubers mass influences the potatoes yield indirectly, through the number of stems and tubers. The highest effect from the increase of seed tubers mass, formed within the clone, is achieved in relatively small fractions (< 50 g), and seed material with the mass from 50 to 90 g differs in its productive properties insignificantly.

The research results to determine the influence of planting width (75 and 90 cm) and storage conditions (using forced blowing systems of the third, the fourth and the fifth technological order) on the shelf life of seed potatoes of various ripeness groups during long-term storage (5 months) are presented in the article. It has been established that changing the planting width up to 90 cm and using forced blowing systems of the fifth technological structure can reduce the natural loss of sprouted tubers, and as a result to increase the potatoes storability.

The research results on the use of humous, complex micronutrients in chelated form (Biovermtehno, Ecogum, Polikom-Potato) in the cultivation of potatoes on sod-podzolic medium loamy soil are presented in the article.

The research results on the effectiveness of macro- and micro-fertilizers on early varieties of potatoes are presented in the article.
The maximum productivity of early potatoes varieties of 53.7–58.3 t/ha was ensured by the application of mineral tuks in doses aimed to potatoes tubers crop yield of 60.0 t/ha, in combination with double foliage spraying with micro-fertilizers of KompleMet-Potato. The profitability of production of ware potatoes, regardless of the variety was maximum and amounted to 102.0–105.7 %.

The research results of positive influence of nanofertilizer «Nanoplant – Co, Mn, Cu, Fe, Zn, Cr, Mo, Se» on survival and also regeneration of microplant in culture in vitro are presented in the article. It is established that concentration of nanofertilizer of 0,200 ml/l as additive to growing medium increases survival of microplant by 12.8 % and also increases net reproduction of plants in vitro by 21.6 %. It is capable to replace microsalts in a growing medium.

The assessment effectiveness are results of microfertilizers Nutrivant Plus, Leafdrip Rost, Leafdrip universal, Leafdrip B, Ecogum complex B, Cu, Zn presented in the article.
The research results showed that it is necessary to take into account the responsiveness of the variety to the composition of the proposed micro-extraction as well as to the targeted cultivation of potatoes in order to give preference to a particular preparation.

The modern biotechnological method related to the current problem of mass virus-free potatoes production for Pskov region in order to obtain virus-free planting material of domestic potatoes varieties free from infection with viral infection for several years, as well as for further use in seed potatoes production in the North-West of Russia is considred in the article. This topic is the most relevant for Pskov region due to the high infection of potatoes sowing material with viral infection, resulting in significant economic losses.
The research results in the direction «original seed production of domestic potatoes varieties using biotechnological methods in vitro» are presented. The formula of growing medium for microplant growth and subsequent propagation of a viral-free seed material has been developed.

The results of influence of mineral oil base preparations on the accumulation of viral infection in seed potatoes production is represented in the article.

The research results of the influence of growth regulators on the morphogenesis of potatoes plants in culture in vitro are presented in the article. As a result, it was found that the development of morphogenesis in all varieties studied by us had a positive effect on the growing medium MS with the addition of Mival-Agro, as it improves the transport of nutrients and accelerates the exchange of processes within the cell.

The research results of the effectiveness of protective-stimulating compounds created on the basis of insecticidal and fungicidal disinfectants, micronutrient fertilizers, plant growth regulators are presented in the article.
The comprehensive efficiency assessment showed that the best option for treatment the medium-sized Scarb potatoes variety was a protective-stimulating composition based on Coyote insecticidal protectant (0.25 l/t) and Maxim fungicidal agent (0.4 l/t) with Albite growth regulator (0.1 l/t). Its application for pre-planting treatment of potatoes tubers allowed to obtain yield at the level of the etalon protectant Emesto Quantum and increase profitability of production by 11.1 %.

The analysis of the current state of selection, seed production and processing of potatoes in Belarus is given. The main problems of the industry are identified and ways for improving its efficiency are proposed: partial reorientation of the directions of crop use in regions; concentration of production of garden potatoes of high quality in large-scale farms; development of seed production of technical potatoes varieties with a starch content of more than 20 %; creation of raw zones for the production of technical potatoes; bringing the varietal structure of potatoes to scientifically based standards.