Table beet (Beta vulgaris L.) is a source of the natural red-colored food dye (E162), highly demanded for the broad spectrum of its biological activity. The relevance of this study is dictated by the lack of knowledge about the dynamics of changes in the crop’s betalain content during the growing season, which impedes identifying the optimal timing of harvesting in order to obtain the dye. This paper presents the results of research into betacyanins (BC) and betaxanthins (BX), separately in the peel and flesh of roots, in 15 differently colored table beet accessions from the collection of the N.I. Vavilov Institute (VIR). There was no statistically significant accumulation of betalains in beets during the growing season. The pigment’s significant fluctuations associated with abiotic environmental factors were shown. The ratio of BC/BX in red-colored accessions was measured: 2.65 in the peel and 2.9 in the flesh. Strong positive relationships were found between BC and BX in the peel (r = 0.97) and flesh (r = 0.79) of red-colored biotypes, which stably persisted throughout the growing season. The beetroot peel was more sensitive to temperature changes, in contrast to the flesh. The negative effect of a temperature increase on betalains in red-colored beetroots intensified on the second or third day. The pigment composition of the flesh was less susceptible to the negative impact of increased temperatures, but reacted negatively to rainfall, becoming more expressed on the second or third day. A conclusion was made about the morphotype with high betalain content. Recommended cultivars are mid-ripening, with rounded and medium-sized roots, a large number of narrow leaf blades, and short and thin petioles.

Research on taxonomic and genetic diversity of cultivated plants provides valuable data that help to clarify how the flora of cultivated plants was formed in a particular region. Paleogenetics, a discipline that developed at the intersection of molecular biology, archeology and genetics, helps to explore plant origin and changes in plant genotype during evolution. By the 12th century, the economy of medieval Northern Russia was based on a developed farming culture. Tracing the origin of its constituent agricultural traditions is an important fundamental task. The objective of this work was to study and identify the species affiliation of carbonized fossil remains of plants that grew in the Russian Northwest in the 12th century using morphological and molecular genetic methods. The results of the morphological analysis of grain fossils showed that most of the unearthed plant material was barley. Other cereals, such as wheat, rye and oat, were also observed. Molecular genetic studies helped to clarify the species affiliation of partially destroyed grains and reconstruct their lifetime morphology.