Alina Kirillovna Koroleva

A method for growing potato seedlings in trays-without transplanting them into open ground – to produce single-tuber plants was investigated. The study aimed to assess the feasibility and effectiveness of this tray-based seedling cultivation technique. During the experiment, 1,187 seedlings were raised and 733 first-year hybrids were obtained from 20 crossing combinations under greenhouse conditions. Field trials confirmed the viability of the resulting single-tuber plants and their conformity to standard development metrics. This cultivation method is proposed as an alternative to traditional approaches. Its efficiency stems from the elimination of the intermediate plant transplanting stage. This approach holds practical significance, enabling the optimization of the breeding process during the seedling stage while maintaining the quality of the resulting material.

Starch is the most important component of potato tubers, the content and structure of which play a decisive role in its use during processing and storage. In this work, a comprehensive assessment of potato samples from the collection Russian Potato Research Centre and hybrids was carried out to determine the starch content during 2021-2024. The assessment was carried out using materials from the genetic collection, including forms of wild and cultivated species, varieties and interspecific hybrids of various origins. In addition to the traditional method of quantitative assessment of starch content based on determining the specific gravity followed by calculation using the empirical formula, a comprehensive assessment was proposed that takes into account the average weight of tubers in the records. About 250 samples of the collection were assessed each year. Based on the results of 2021 and previous studies, 12 samples with a consistently high starch content were identified. The 2022 studies also identified 16 accessions with high starch content, including accessions with complex interspecific origin and interspecific hybrids of species such as S. stoloniferum, S. pinnatisectum, and S. alandiae. In 2023, 10 accessions promising in terms of starch content were identified, including two accessions from the dihaploid collection with a starch content of more than 26%. In 2024, 16 hybrids with high starch content and 3 accessions with a starch content of more than 23% were identified in the analyzed sample. Despite the fact that high starch content requires confirmation of the stability of the trait in subsequent years, as part of the work done, accessions promising for further use in breeding programs were identified, including both varieties and complex interspecific hybrids.

The study of biochemical quality indicators of 26 new potato hybrids was carried out in order to determine the ones mostly suitable for processing into starch and potato products and for use as table variety. An express method was used to determine dry matter (DM), Evers method was used to determine the total starch content of tubers, the polarimetric method and a glucometer test were used to determine reducing sugars, glycoalkaloids and inorganic phosphorus were determined by spectrophotometric method. There have been selected 5 hybrids suitable for industrial processing and as a source material for breeding. One potato hybrid with 25,06 % content of DM, more than 18,22 % of starch met the requirements for potatoes used for processing into starch and starch products; another potato hybrid can be recommended for the production of fried potato products according to the parameters: DM – 22.40 % starch – 16.18 %, reducing sugars – 0.23 %, glycoalkaloids – 62,0 mg/kg. Three of the studied hybrids with the content of DM of more than 22 %, starch not less than 16%, reducing sugars 0.2-0.4 % and glycoalkaloids 60-126 mg / kg may be used for the production of other types of potato products. The rest of the hybrids can only be recommended for use as table potatoes. The relationship between indicators affecting the quality of potato products has been revealed. Correlations were established between the mass fractions of: dry matter and starch in the tuber (r = 0.98) – high correlation; reducing sugars and glycoalkaloids (r = 0.68); tuber dry matter and glycoalkaloids (r = 0.59); dry matter and glucose (r = -0.61); starch and glucose (r = -0.58) – average correlations. It has been established that the mass fraction of reducing sugars and the direction of rotation of the plane of polarization of light by sugars change non-linearly under different temperature conditions of sample storage.