Purpose. To investigate the varietal characteristics of the hemp plants for improving the quality indices of the soil they grow in, determine the amount of inorganic elements in the soil, level of their accumulation in plant stalkі and seeds. Methods. Field and spectrometric methods were basic. The results were processed using conventional methods in agriculture, crop growing and statistics. Variants of the experiment were as follows: varieties ‘Hliana’, ‘Hlesiia’: 1) soils; 2) stalks; 3) seeds. Schemes of experiments included: a) technical maturity of plants, row spacing 45 cm; b) tech­nical maturity of plants, row spacing 15 cm; c) biological maturity of plants, row spacing 45 cm; d) biological maturity of plants, row spacing 15 cm. Results. The amount of the accumulation of alkaline earth metals and their compounds by seeds and stalks of hemp plants depending on their content in vegetation soils was determined. It was found that stalks of the ‘Hlesiia’ plant accumulated strontium (Sr) and its compounds far less than that of ‘Hliana’, whereas in the seeds of the ‘Hlesiia’ variety the content of this chemical element was higher comparing with the previous variety by 70 and 78%, respectively. The difference in the accumulation of barium (Ba) compounds in seeds of hemp plants was not significant, while the tissues of the plant stalks of the ‘Hlia­na’ variety accumulated its compounds significantly more as compared to the ‘Hlesiia’ variety. The degree of influence of the variety, feeding area and the maturity stage on the processes of magnesium compounds (Mg) accumulation by plants was not revealed. Plants of the ‘Hlesiia’ variety accumulated far less calcium (Ca) and its compounds in the stalk tissues as compared to the plants of the ‘Hliana’ variety: in variants of the technical maturity stage of plants with row spacing 45 cm (a) and d – plants of narrow-row sowing (15 cm) in the biological maturity stage 30,94 and 15,95 mg/kg more in the presence in soil and in variants of the technical maturity stage of plants of narrow-row sowing (15 cm) and in the biological maturity stage with broad-sowing (45 cm) 34.54 and 24.19 mg/kg less in the presence in soil. Conclusions. The indices of accumulation of alkaline earth metals by hemp plants were significantly affected by the concentration of compounds of a certain chemical element in the arable layer, the level of energy (light) obtained by plants during vegetation, the varietal features of hemp, the stages of organogenesis of hemp plants and the specificity of their aboveground parts – stalks to accumulate these chemical elements as well as cumulate them by seeds. The varietal dependence as for accumulation of heavy metals by hemp plants tissues and seeds was established. In order to obtain environmentally friendly products, it is necessary to take into account the varietal features of plants concerning the ability to absorb and accumulate the relevant chemical elements and their compounds in the process of hemp culti­vation.

Purpose. Identifying the features of the seasonal growth rhythm, development of the plants, morphological and biological differences in monoecious introduced and domestic varieties of Cannabis sativa L. in the North-east region of Ukraine. Methods. The research was conducted from 2014 till 2019. The following research methods were employed: field (phenological observations, sampling for laboratory analysis), microscopic (study of the morphological structure of glandular and cystolithic hairs on vegetative and generative organs, determination of the size and density of hair formation), laboratory and analytical (determination of the content of cannabinoid substances by thin layer and gas-liquid chromatography), biomorphological me­thods (analysis of morphological characteristics of plants). Chemical analysis for the content of cannabinoid substan­ces was carried out in the laboratory of the breeding and seed production department of the Institute of Bast Crops of the NAAS of Ukraine (Glukhiv, 2014–2019). The content of neutral substances [cannabinol (CBN), cannabidiol (CBD), tetrahydrocannabinol (THC)] and acids (CBDA, THCA) was determined by using a thin layer chromatography (TLC) and gas-liquid chromatography (GLC) methods. For the study, 11 monoecious varieties of C. sativa: ‘YuSO 1’, ‘YuSO 31’, ‘Hliana’, ‘Viktoriia’, ‘Hlesiia’, ‘Hlukhivskyi 46’, ‘Hlukhivski 51’, ‘Zoloto­niski 15’ and 3 introduced varieties: ‘Fedora 17’, ‘Felina 32’, ‘Futura 77’ (France) which differed among themselves in morphological, biological, genetic, ecological-geographical and economically valuable characteristics were selected. Results. Biological and morphological characteristics of modern monoecious varieties of C. sativa were investigated depending on the ecological and geographical zones of origin, conditions of the growing season and the stage of ontogenesis. The functional interdependence between the formation of specialized excretory structures and the content of cannabinoid substances in plants of different varieties of C. sa­tiva was revealed. The following promising varieties of C. sativa in a ration of ((THC + CBN) ≤ CBD) point the possibility to use them as the source material for creating the medicinal varie­ties of plants with a high content of CBD. Conclusions. Nowadays C. sativa is the main source of phyto material for industrial production of natural CBD. In recent years, high-yielding varieties of C. sativa have been created, which, together with high commercially valuable traits, did not contain psychoactive THC and had an insignificant amount of CBD. The results of the research indicated the features of the seasonal growth rhythm, development of the plants and the morphological and biological features of modern monoecious introduced and domestic varieties of C. sativa in the North-east region of Ukraine. The low correlation between the content of cannabinoid substances and their acids in varieties, which are cha­racterized by the low content of cannabinoid compounds was established. According to the developed own classification (THC + KBN): CBD, varieties with a predominant CBD content ‘Hlukhivskyi 46’, ‘Zolotoniski 15’, ‘Hliana’ which are of significant medicinal value were identified.