Relevance. Currently, there is an increased interest in medicinal plants and preparations from natural herbal raw materials. This is due to the fact that biologically active substances of plants are more easily included in vital processes and do not cause side effects in humans. They can be products of primary (vitamins, fats, carbohydrates, proteins) and secondary biosynthesis (alkaloids, glycosides, tannins). Plants always contain a complex of biologically active substances, but one or several have a therapeutic and prophylactic effect. They are classified as active ingredients and are used in the production of medicines. Some of the promising medicinal plants are species from the genus Dioscorea, for example, Dioscorea alata L., containing a complex of biologically active substances. The aim of this work is to study the effect of humidity and the level of mineral nutrition in the root environment on the accumulation of biologically active compounds in the tubers of the dioscorea winged plant, adapted to in vivo conditions on an ion-exchange substrate of various chemical composition and agrophysical properties.Results. It has been shown that Dioscorea alata L. plants are able to accumulate the greatest amount of starch, dry matter, ascorbic acid, and flavonoids in an ion-exchange substrate modified with 1 g/l of the coarse hydrogel fraction. The data obtained can be used for practical purposes.

Relevance. One of the main components of the spectrum of sunlight is ultraviolet rays – invisible to the human eye short-wave radiation. The influence of these rays on plant life was considered insignificant until recently, but recent studies have shown the fallacy of such conclusions. Ultraviolet has a beneficial effect not only on the human body and animals, but also on plants, including – crops. The destruction of the ozone layer is currently continuing under the influence of anthropogenic factors. In this regard, the study of the effect of ultraviolet radiation on living organisms, including plants, is very relevant from both theoretical and practical points of view. The epidermis of plant leaves and seed shells are permeable to medium-and long-wave UV radiation, so of particular interest is the ultraviolet radiation of the Sun and artificial sources of ultraviolet radiation in the range of 400...180 nm.Purpose of work: to assess the nature of the impact of ultraviolet radiation in the time mode on watermelon seeds using cytogenetic analysis.Methods. The material for research was the seeds of the watermelon variety "Astrakhan". The studies were conducted in 2017-2018.Results. The results of studies have shown that long-term exposure to ultraviolet radiation can affect the physiological processes and anatomical structure of plants, as well as have serious genetic changes: aneuploidy, cytotomy, pyknosis and various chromosomal aberrations that lead to mutations or death of plants. However, plants acquire useful mutations with short-term exposure-0.5-2 hours, which can be used later in selection.

Relevance. Grain of vegetable pea varieties is processed at canning factories, frozen, dried, and consumed fresh. Industrial cultivation of peas can be made more environmentally friendly by using biological preparations that contain growth-stimulating bacteria, for example Rhizobium species. With additional inoculation with rhizobacteria, legumes have higher values of traits characterizing vegetative development, biochemical parameters and yield; their immunity and resistance to abiotic stress increases as well.Methodology. The aim of our study was to evaluate the effect of additional inoculation of Rhizobium leguminosarum strain 245a on biometric and physiological parameters and yield of vegetable pea varieties. The experiment was carried out at Krymsk Experiment Breeding Station – a branch of VIR (Krasnodar Region, Krymsk). We studied six commercial cultivar: Prima, Mayak, Alpha 2, Vesta, Parus (leafless morphotype) and Patriot. The seeds were treated the day before sowing with an aqueous solution of the biopreparation Rhizotorfin (produced by ECOS BIOPREPARATIONS, St.Petersburg) and with water in the control variant.Results. The use of the preparation had a growth-stimulating effect on vegetable pea plants. An increase in the length of plants, the height of attachment of the lower pod and the number of completed pods on the plant was found. An increase in the content of dry matter in the total biomass of plants, stems with leaves and pods was noted when using Rhizotorfin. Also, inoculation with rhizobacteria contributed to an increase in yield. The effectiveness of the biopreparation depended on the conditions of the year. The maximum difference between the values of the studied traits for the control and treatment variants was in 2023 - with a uniform distribution of precipitation and optimal temperatures during the growing season. A genotype-dependent reaction of vegetable pea plants to seed treatment with bacteria Rhizobium leguminosarum strain 245a was revealed. The most responsive to additional inoculation is the variety Parus of the leafless morphotype. The values of most biometric and physiological traits and yield in this genotype were significantly higher in the variant with the use of the Rhizotorfin biopreparation. Based on the results obtained, we recommend using the Rhizotorfin biopreparation when growing the variety Parus for commercial production.

June 9-13, 2014 in Makhachkala hosted XI International scientific-methodical conference on the theme: «Introduction, conservation and use of biological diversity of cultivated plants», organized by FGBNU VNIISSOK, Dagestan Research Institute for Agriculture and GBS DSC RAS. The conference was attended by scientists from Russia, CIS and foreign countries. Due to the conference Dagestan turned out to be a prime location for the cultivation of both traditional and non-traditional plants with a high content of biologically active substances, as well as a training ground for resistance tests because of the combination of mountain and plain zones.