Purpose. To establish the optimal seeding time and depth of ‘Dniprovskyi 39’ and ‘Vinets’ sorghum varieties, to prove their effect on the crop photosynthetic capacity in the Right-Bank Forest-Steppe of Ukraine. Methods. Field, laboratory, comparative, analytical, generalizing, mathematical and statistical. Results. It was proved that the best results of crop photosynthetic capacity of sorghum were obtained by sowing in the first decade of May (the second sowing period) at a seeding depth of 4–6 cm. Accordingly, the leaf surface area in these variants reached its maximum during the “panicle-blooming” period and equated 36.13–38.81 thousand m2/ha for the ‘Dniprovskyi 39’ variety and 34.23–36.91 thousand m2/ha for the ‘Vinets’ variety. By sowing seeds in the third decade of April (the first sowing period) at the seedining depth values described above the leaf surface area of the varieties was slightly smaller and amounted to 29.56–31.20 thousand m2/ha for the ‘Dniprovskyi 39’ variety and 27.76–29.40 thousand m2/ha for the ‘Vinets’ variety. By sowing seeds in the second decade of May (the third sowing period), the leaf surface area was 30.68–32.92 thousand m2/ha for the ‘Dniprovskyi 39’ variety and 29.08–31.32 thousand m2/ha for the ‘Vinets’ variety. The highest photosynthetic potential was obtained for sorghum plants in the second sowing period at the seeding depth of 4–6 cm and was 1.27 and 1.34 million m2/ha for the ‘Dniprovskyi 39’ variety and 1.16 and 1.22 million m2/ha for the variety ‘Vinets’. In the first sowing period, this indicator was slightly lower and amounted to 1.18 and 1.23 million m2/ha for the ‘Dniprovskyi 39’ variety and 0.98 and 1.02 million m2/ha for the ‘Vinets’ variety respectively. In the third sowing period, it was the smallest one and equated 1.09 and 1.13 million m2/ha for the ‘Dniprovskyi 39’ variety, and 0.88 and 0.93 million m2/ha for the ‘Vinets’ variety at the optimal seeding depth. The photosynthetic potential was lower at the seeding depth of 2 and 8 cm, which is explained by the different soil and climatic parameters during a certain period of sorghum plant vegetation. The highest value of the photosynthetic capacity net indicator was obtained by sowing seeds at the optimal time and the optimal seeding depth and it equated 3.84–4.02 g/m2 per day for the ‘Dniprovskyi 39’ variety and 3.79 – 3.98 g/m2 per day for the ‘Vinets’ variety. Conclusions. It has been established that the sorghum plants had better vegetation and formed photosynthetic capacity by sowing seeds in the first decade of May at the planting depth of 4–6 cm, which we recommend for growing this crop in the Right-Bank Forest-Steppe of Ukraine.

Purpose. To reveal features of formation of productivity of modern sugar beet hybrids of domestic selection. Methods. Field, laboratory. Results. Studies show that the lowest yields of sugar beets were obtained in 2016, 2017 and 2019. Moreover, the conditions of the unstable humidification zone of the Right-Bank part of the Forest-Steppe of Ukraine were mainly characterized by unstable precipitation, a decrease in their amount, as well as increased average daily air temperatures. Therefore, the selection of high-yielding hybrids of sugar beets to obtain a high level of productivity is relevant. As evidenced by the data comparing the yield of sugar beet root crops on the test site, they significantly exceeded the average indicators for Kiev region by 10.7–20.0 t/ha, and only in arid 2016 the difference was minimal – 4.6 t/ha. The high stability of the trait “sugar content in root crops” is inherent not only in hybrids with low parameters of its manifestation, but is largely determined by the genetic characteristics of the hybrid. Three clusters were identified based on the reaction of hybrids to growing conditions. The first cluster included triploid hybrids: ‘Zluka’, ‘Oleksandriia, ‘Olzhych’, ‘Kvarta’ and ‘Konstanta’, the second one – the triploid hybrid ‘BTs ChS 57’ and diploid ‘Vesto’, the third cluster - the triploid hybrid ‘Sofiia’ and diploid ‘Ukrainskyi ChS 72’. Conclusions. Proper selection of high-yielding hybrids resistant to adverse growing conditions in the zone of unstable moisture of the Forest-Steppe of Ukraine is extremely important, because the biological characteristics of hybrids affect 45% of the amount of sugar harvest, but the growing season by 33% and the interaction of factors was 17%. It was found that despite the difficult weather conditions, the highest yields were formed by hybrids: ‘Anichka’ – 70.1 t/ha, ‘Ramzes’ – 70.5 t/ha, ‘Romul’ – 73.0 t/ha and ‘BTs ChS 57’ – 73.4 t/ha. But the maximum sugar content in root crops was in hybrids: ‘Ukrainskyi ChS 72’ – 17.3%, ‘Zluka’ – 17.3% and ‘Sofiia’ – 17.7%. Accordingly, the maximum sugar harvest was provided by hybrids: ‘BTs ChS 57’ – 12.1 t/ha and ‘Romul’ – 12.2 t/ha.

Purpose. To study the economic and biological characteristics and to reveal the genetic potential of various hybrids of Chinese cabbage depending on the climatic zone of cultivation. Methods. In the experiment, hybrids of Chinese cabbage ‘Pioner F1’ (control), ‘Villi F1’, ‘Manoko F1’, ‘Orient Star F1’, ‘Vitimo F1’, ‘Sprinkin F1’, ‘Summer Highland F1’, ‘Suprin F1’, and ‘Richi F1’ were evaluated. The experiment was laid out in a randomized block design with four replications with a single plot area of 21 m2. The container seedlings (40 days old) were planted in the middle of April according to the scheme 70 cm by 25 cm. Results. Having been planted at the same time, seed germination over the studied hybrids was not simultaneous. The first sprouted seeds (4 days after seeding) belonged to hybrids ‘Villi F1’, ‘Manoko F1’, ‘Orient Star F1’, and‘Summer Highland F1’. Seeds of the other hybrids started active germination on the 5–6 days after seeding. The highest yield of the cabbage heads was obtained from hybrids ‘Villi F1’ (31.7 t/ha) and ‘Sprinkin F1’ (28.7 t/ha), which was 10.0 and 7.0 t/ha more than in the control variant. The yield of ‘Summer Highland F1’ was 24.9 t/ha and ‘Suprin F1’ 24.6 t/ha. Under the conditions of unstable soil moisture, hybrids ‘Villi F1’and ‘Sprinkin F1’ appeared the most productive and ensured yield increase of 10.0 t/ha and 7.0 t/ha, respectively, compared to the control; and crop commercial quality was high. The highest percentage of dry matter (DM) content was in ‘Summer Highland F1’ (6.2%) followed by ‘Sprinkin F1’ (5.9%), which was 1.1% and 0.8% more than in the control. There was no significant difference between the values of the total sugars content over the variants. They ranged between 1.7 and 2.1%, which was similar to the control values. The content of nitrates in the cabbage heads of the studied Chinese cabbage hybrids was within the tolerance limit and amounted to 600 mg/kg (raw mass). Conclusions. Phenological observations of plant development and their biometric indices, depending on the varietal characteristics, indicate that under the conditions of unstable soil moisture, hybrids ‘Villi F1’ and ‘Sprinkin F1’ were more yielding and ensured yield increase of 10.0 t/ha and 7.0 t/ha, respectively, compared to the control. The crop commercial quality was high. The long growing season of ‘Richi F1’ (93 days) did not affect the crop quality and yield and demonstrated the lowest productivity compared to the control and the other experiment variants.

Purpose. The adaptation of regenerant plants to environmental conditions is the final stage of micropropagation. According to a number of authors, when in vitro plants are transferred to in vivo non-sterile conditions, a significant percentage of mortality is recorded. In a previous publication, the regenerative capacity of strawberry (Fragaria vesca L.) in vitro tissues on MS culture medium (Murashige & Skoog, 1962) and a regenerants was obtained (Chornobrov O. Yu., 2019). The objective of the study is to develop an optimal protocol of acclimation of in vitro F. vesca plants to in vivo conditions. Methods. Biotechnological and statistical methods of research were applied. For the research ‘Ruiana’ and ‘Zhovte Dyvo’ cultivars were used with in vitro cultivation cycle of 30–35 days. Prepared plants were planted in 0.33 L plastic contai ners, one piece in a mixture of coconut substrate and perlite (3:1). Plants were kept under high relative humidity (85–90%) conditions for 3–5 days, 6–8 days and 10–14 days. The studies were carried out in the Plant Biotechnology Laboratory of SS of NULES of Ukraine “BFRS” during 2019–2020. Results. The duration of Fragaria vesca regenerant plants exposure in conditions of high relative humidity significantly affected adaptation efficiency. The proportion of ‘Ruiana’ and ‘Zhovte Dyvo’ plants adapted to the greenhouse conditions were 47.6 ± 2.5% and 60.0 ± 1.7%, respectively, when the plants were kept for 10–14 days. A significant efficiency of plant adaptation (more than 70%) was obtained under condition of preliminarily exposure the roots of the plants in an auxin solution for 25–30 minutes with daily application of 30% solution of glycerine as foliar spray. The plants adapted to the greenhouse conditions had pigmentation characteristic of the variety, without signs of chlorosis and vitrification. Conclusions. An optimal protocol for in vitro adaptation of F. vesca cultivars to in vivo conditions was developed and viable plants were obtained. Further research will be aimed at studying the growth and development of F. vesca regenerant plants in open ground.

Purpose. Develop a simplified method for estimating the color of flour and pasta using Adobe Photo Shop® software. Methods. The research material was grain of varieties and selection lines of wheat species Triticum durum, T. dicoccum, T. timopheevii bred in the Рlant Production Institute nd. a. V. Ya. Yuryev and samples of the National Center for Genetic Resources of Plants of Ukraine, 2018–2020 harvest. Batch of flour and pieces of dough were scanned using EPSON Scanner 010 F. Color was evaluated using Adobe PhotoShop®. The level of carotenoids was determined by spectrophotometric method. Results. Visual assessments of flour and pasta color, presented by different researchers, differ significantly (up to 2–3 points on a 9-point scale). At the same time, the use of the developed method of express color evaluation of flour and pasta samples in Adobe PhotoShop® with the color evaluation system L*a*b*, used in modern reflectometers, allows to obtain data in numerical value and provides high accuracy. In the case of the developed me­thod, correlations were established between the content of carotenoids and the index b* of flour (r = 0.41 / ≤ 0.05) and pasta (r = 0.60 / p ≤ 0.001) and allowed to select the best in flour color selection lines 10-56, 10-65, 14-153, sample T. durum var. falcatomelanopus, in pasta color – lines 10-56, 10-65, 11-29, 12-3. Conclusions. The developed method provides high accuracy and can be used to evaluate the color of pasta and wheat flour, simplifies the evaluation of test samples, standardizes the parameters of agricultural products and avoids subjective judgment. The established weak correlation between the carotenoid content and the b* value of flour indicates the effect on the color of flour not only orange but also yellow and red pigments, and the ave­rage correlation between the carotenoid content and the b* value of pasta indicates the influence of the products of polyphenols oxidation reactions of wheat grain. The best in color flour and pasta lines were selected for breeding work to increase the content of carotenoid pigments in grain.

Purpose. To substantiate the features of the classification of morphobiological and economically valuable indicators of highbush blueberry varieties of Vaccinium corymbosum L. Methods. The studies were carried out during 2012–2019. Research methods: field (visual examination of the manifestation of morphological signs of vegetative and generative organs of blueberry plants), laboratory (determination of the content of vitamin C, total sugar, pectin, carotenes, anthocyanins, flavonoids, total acidity in berries), analytical, comparative, statistical (cluster analysis). Results. Over the years of research, varieties of highbush blueberries were characterized by a stable manifestation of homogeneous morphological traits and economically valuable performance indicators. In particular, the studied varieties are classified according to ripeness groups: very early: ‘Fiolent’; early: ‘Draper’, ‘Huron’, ‘Clockwork’, ‘Cargo’, ‘Laska’; medium: ‘Blue Ribbon’, ‘Top shelf’, ‘ZF08-070’, ‘Mavka’; late: ‘Liberti’, ‘Last Call’ and very late: ‘Aurora’, ‘Overtime’. It was determined that the quantitative morphological traits of highbush blueberry varieties that influenced the formation of plant productivity include such traits as growth vigor, leaf length, leaf width, inflorescences lengthwise, bunch density, fruit size. Economically valuable indicators of suitability of highbush blueberry varieties remained stable within the ripeness group. The highest yield (19.5 t/ha) was provided by the mid-season variety ‘Mavka’ of domestic selection. The yield of berries from the bush of this variety was also high and amounted to 7 kg. The studied performance indicators were low in the variety ‘Blue Ribbon’ – 10.2 t/ha and 2.4 kg, respectively. The minimum and maximum values of the manifestation of characteristics will serve to establish the limiting boundaries of its variation in the next modeling of economically valuable indicators of highbush blueberry varieties. Conclusions. Such morphobiological characteristics of highbush blueberry varieties, as plant growth vigor, leaf length, leaf width, inflorescences lengthwise, bunch density, fruit size are closely related to plant productivity, berry yield per bush, berry weight and yield. Therefore, they can be involved in the development and improvement of the model of suitability indicators of highbush blueberries for distribution in Ukraine.

Purpose. To determine the content of biochemical compounds in fruits of M. domestica Borkh. varietal samples, select the most promising ones for use in further breeding, and recommend for use in various directions, given the biochemical complex of signs, taste and marketability of the fruit. Methods. We used generally accepted methods for determining the biochemical composition of fruits (soluble so­lids (SSR) according to GOST (State Standard System) 29030-91, total sugars according to GOST 8756-13.87; polyphenol composition according to the method of L. I. Vigorov (1968), vitamin C according to the method of A I. Ermakov (1972); tit­rated acids – according to GOST 25555.0-82). Results. Nine cultivars of apple trees were analyzed for the biochemical composition of fruits, namely the apple tree cultivar ‘Vydubytska Plakucha’ (‘V. p.’) and various hybrids created on its basis from the collection of the fruit plant acclimatization department of the M. M. Hryshko National Botanical Gardens of National Academy of Sciences of Ukraine. Selected forms are sources of 1–5 important biochemical characteristics (solids content, glucose, sugars, ascorbic acid, titratable acid) and promising for use in breeding. According to the dry matter content – the lowest rate was found in hybrid ‘V. p.’ × ‘Renet Symyrenko’ (16.68%), the highest in the hybrid – ‘V. p.’ × ‘Renet Oranzhevyi Coksa’ (22.87%), rates of ascorbic acid content varied within (6.0–12.25 mg%), total sugars (10.37–18.23), acids (0.74–1,67 respectively). The most interesting for introduction and breeding are hybrids with a high content of biochemical parameters, namely: ‘V. p.’ × ‘Renet Oranzhevyi Coksa’, ‘V. p.’ × ‘Golden Delicious’ and ‘V. p.’ × ‘Parmen Zymovyi Zolotyi’. Conclusions. The content of the biochemical composition of the fruits, taste and marketability were characterized, and varietal samples of hybrids of the apple tree ‘Vydubytska Plakucha’ were distributed in the directions of use in order to improve the quality of life of the population. According to the biochemical indicators of the cluster analysis of the studied apple hybrids, close relationships were found between the three groups necessary in the future for breeding when selecting parental forms for an improved biochemical composition of the fruit (including hybrids ‘V. p.’ × ‘Renet Oranzhevyi Coksa’, ‘V. p.’ × ‘Golden Delicious’ and ‘V. p.’ × ‘Parmen Zymovyi Zolotyi’, titrated acid hybrids ‘V. p.’ × ‘Starkrimson’, ‘V. p.’ × ‘Parmen Zymovyi Zolotyi’ and ‘V. p.’ × ‘Renet Symyrenko’, tannins hybrids ‘V. p.’ × ‘Slava Peremozhtsiam’ and ‘V. p.’ × ‘Starkrimson’); and to expand the assortment of apple trees according to the planned commercial signs. Hybrids of the apple-tree cultivar ‘Vydubytska Plakucha’, created in the NBG using old and valuable modern apple-tree cultivars, indicate the promise of producing high-yielding, large-fruited varieties with a high content of biologically active substances

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.

Purpose. To analyze the divergence of early maturing source material of corn Zea mays L. in heterosis breeding for the genetic base formation at the State Institution the Institute of Grain Crops of the NAAS of Ukraine. Methods. Field (comprehensive assessment of morphobiological and economically valuable characteristics of the source material and maize hybrids) individual selection, cumulative and recurrent selection, backross and testcrosses bree­ding methods; laboratory; analysis and synthesis; statistical. Results. The results of research on the analysis of the divergence of early maturing corn source material in the conditions of the Steppe of Ukraine has become a developed harmonized working collection of corn breeding samples adapted to the stressful conditions of this region. The gradual cyclical improvement of the lines made it possible to form the core of the genetic diversity of FAO 150–290 early maturing specimens of the southern ecotype, which are competitive in heterosis breeding. The complexity of breeding for early maturity in the steppe conditions is due to the lack of material adapted to the stress factors of the South of Ukraine. The available early maturing lines of the world collection F2, F7, Ер1, Ма21, Ма23, Со125, Со255, См7, PLS61, S72, etc., were distinguished by high cold resistance, good starting plant development, intensive accumulation of dry matter during ripening, but not adapted to the deficiency of moisture in the soil and high summer temperatures. According to the results of the experiment, it was revealed that, in terms of breeding, lines of Lancaster plasma (DK427 and DK633) were the most plastic, due to which a number of new mid-early lines were obtained, for example DK2/427, DK267, DK266/417, DK633/266, DK296, etc., which were included in the registered hybrids. Formation of the genetic base of early maturing maize source material for heterosis breeding and systematization accor­ding to different breeding characteristics provided a balance of samples of alternative components, which will be further used to model heterosis hybrids in the early maturing group. Conclusions. The updated basic collection of lines is represented by the samples of plasma Iodent: DK744SVZM, DK216SVZM, DK4173SVZM, DK235zS, DK257zM, SV, DK365SVZM, DK777ZMSV, DK733-7zM,SV, DK315SVZM; Lancaster: DK296zS,VM, DK633/266zS,VM, DK2965ZSZM, DK2953 ZSZM, DK3023 ZSZM, DK236zS,ZM; Raid (SSS): DK232MV, DK2323MV, DK239MV; Mixed: DK253ZSZM, DK273MV, DK272zS, DK281SV, DK233zM,SV, DK959MV, DK9527 ZSZM, DK247MV, DK2442MV, which is the basis of the genetic diversity of early ripening corn samples included in the State register of plant varie­ties suitable for dissemination in Ukraine.

Purpose. Identify the peculiarities of the growth and development of plants, formation of productivity of sweet sorghum hybrids for different widths of row spacing, crops density and the use of the growth stimulant Vympel 2 in the zone of the Forest-Steppe Ukraine. Methods. The study used hybrids ‘Dovista’ and ‘Huliver’. The width of the row spacing was 45 and 70 cm for the density of the crops: 150 thousand pcs/ha, 200 thousand pcs/ha, 250 thousand pcs/ha. Sorghum seed treatment was carried out using Vympel 2 (0.5 l/t) growth stimulant and its additional foliar application in the tillering stage of the crop (0.5 l/ha). Results. Studies have revealed that the ‘Dovista’ hybrid has a significant potential for productivity due to a longer growing season. At different widths of row spacing and density of plants standing, the hybrid ‘Dovista’ yield exceeded the average by 3.6 t/ha of‘Huliver’ hybrid. The yield increase at the level of 7.3–13.0 t/ha was obtained in the variant of application of growth stimulant Vympel 2 at 45 cm of row spacing and changes in sowing rates from 150 to 250 thousand pcs/ha. Similar variants of experiment at 70 cm of width of row spacing ensured collection of vegetative mass of sweet sorghum at 6.7–12.6 t/ha more than in cont­rol variants. The growth stimulant Vympel 2 increased the accumulation of dry matter in ‘Dovista’ hybrid with a row spacing of 45 cm and various seeding rates by 1.3–4.3 t/ha, whereas with a row spacing of 70 cm – by 1.2–3.5 t/ha. In the ‘Huliver’ hybrid in similar experiments, an increase in dry matter was obtained at the level of 1.7–3.9 t/ha, and the application of the growth regulator ensured the collection of dry matter of sweet sorghum by 1.3–3.0 t/ha above the control variants. Total sugar content in the variants of the experiment was biased. Application of seed treatment with growth stimulant Vympel 2 (0.5 l/t) followed by foliar application in the tillering stage (0.5 l/ha) increased the content of total sugars by 0.15, but this slight deviation was within the experimental margin. Conclusions. The highest yield of green mass at a density of 250 thousand plants per hectare and seed treatment with growth stimulant Vympel 2 (0.5 l/t) + foliar application in the tillering stage (0.5 l/ha) provided the ‘Dovista’ hybrid – 98.8 t/ha, which is 5.3 t/ha more than in the ‘Huliver’ hybrid for the width of the row spacing of 45 cm. In the phase of physiological maturity of the grain, the content of total sugars in sweet sorghum was, on average, at the level of 15.0%, in the ‘Dovista’ hybrid – 15.4%, in the ‘Huliver’ hybrid – 14.7%.