Significance. Potato products seem to be gaining popularity in Russia, especially potato chips and french fries. The processing of potato into food products reduces storage losses and the amount of transportation needed and allows the nutritional potential of potato to be harnessed fully. However, only a minor part of all produced potato is processed in Primorsky kray by small-scale enterprises. The lack of high quality raw material is the main reason for that. The research aim was to evaluate potato varieties from our collection nursery for the traits that determine potato suitability for the production of potato chips and french fries.Materials and methods. The research was carried out in the experimental fields of the Department of potato breeding and horticulture, FSBIS “Federal Scientific Center of Agricultural Biotechnology of the Far East named after A.K. Chaiki”, in 2019-2021. One hundred and eighty potato hybrids of various origin and from different maturity groups were used as the research object. The evaluation was conducted according to the guidelines on the assessment of potato varieties for their suitability for processing and storage with a few additions.Results. The conditions in 2019 were the most favorable for yield formation in medium-early (32.3 t/ha), mid-season (31.9 t/ha) and medium-late (33.1 t/ha) varieties. Early varieties were observed to have the highest mean yield in 2021 (34.0 t/ha). Biochemical parameters (the dry matter content) and the content of reducing sugars were optimal (22-24 % and less than 0.26 %, respectively) in varieties Vektar, Zhuravinka, Darnitsa, Pamyati Rogacheva, Lady Rosetta, VR 808. The morphological parameters (the shape of tubers, the quantity and depth of potato eyes) of varieties Severnyi, Bryanskii delikates, Danaya, Kurazh, Sante, Dubrava, Nayada made them the most suitable for the production of potato chips. Varieties Kolette, Narka, Innovator, Vdokhnovenie were determined to be the most suitable for processing into french fries. Based on the complex of morphological and biochemical parameters, 29 potato varieties were selected for the production of potato chips and 26 varieties were approved for the production of french fries. The degree of suitability varied from 6.4 to 8 points. Under the conditions of Primorsky kray, varieties Sante, Tanai, Nayada. Alyaska, Krasa Meshchery, Kazachok generate the most interest for the production of potato chips. Varieties Liga, Vesna Belaya, Udacha, Utenok, Charodei, Ocharovanie, Rikarda appear to be the most suitable for processing into french fries. These varieties have a high degree of suitability after harvest and good yield.

Relevance. Potato starch is widely used in the food, textile, perfume and pharmaceutical industries. The starch content and the size of starch granules in potato tubers are varietal characteristics (Solanum tuberosum L.). The knowledge of morphological properties of starch plays a key role in the technologies for the production of consumer and industrial goods.Materials and methods. The studies were carried out in 2020-2021 at the experimental base of Federal State Budget Scientific Institution “Federal Scientific Center of Agricultural Bio-technology of the Far East named after A.K. Chaiki” (Primorsky Krai). The object of the research were 11 varieties of different maturity dates. Morphological structure of starch granules was evaluated by image analysis on Countess II FL automated cell counter.Results. The varieties studied had predominantly rounded and oval pellets regardless of maturity and genetic origin. Differences in starch granule size depending on tuber size and ripeness group were noted. Early maturing varieties had granule size less than 20 microns regardless of tuber fraction. The exception is the variety Queen Anne, in small tubers of this variety starch granules larger than 20 microns is 67.86%. It was noted that the proportion of medium and large grains increased in varieties with a longer growing season. For example, the variety Augustin medium-ripening had a proportion of medium and large grains in the large and small tuber of 47.72 and 41.48%, respectively. The maximum number of grains larger than 20 microns was observed in the mid-late varieties Kazachok (63.77%) and Smak (92.22%).Conclusion. The method using a cell counter and subsequent processing of microphotographs of starch granules is an accessible, economical, simple and effective approach to phenotyping potato varieties and hybrids of Solanum tuberosum L. by physical and chemical parameters of starch. This method can be used for accelerated analysis of a large number of samples on a limited amount of natural material, including in field and farm laboratories.