РАЗВИТИЕ ЗИМУЮЩЕЙ ИНФЕКЦИИ SCHIZOTHYRIUM POMI (MONT. & FR.) ARX. В ЧЕРНОМОРСКОЙ ЗОНЕ КРАСНОДАРСКОГО КРАЯ

One of the forgotten crops is turnip, which originates from Western Asia. It belongs to the oldest vegetable plants and has been cultivated by man for over 4 thousand years. Successful cultivation of turnip is possible if the elements of cultivation technology are observed. Therefore, the purpose of the research was to establish the optimal sowing dates of turnip seeds and their impact on plant productivity and quality indicators of the root crop in open ground conditions. The research was conducted in 2023–2024 in the conditions of Western Polissya of Ukraine. Turnip seeds were sown in the 2nd and 3rd decades of April, and the 1st, 2nd and 3rd decades of May. The varieties Zolota Kulya, Purpurlepop, Purpurova and Geisha were used in the experiment. The control was the variant in which the seeds of the Zolota Kulya variety were sown in the 2nd decade of April using a wide-row method with a row spacing of 45 cm. The experiment determined the duration of interphase periods of growth and development of turnip varieties, the mass of leaves and turnip roots, the total yield of root crops and their quality depending on the time of sowing seeds. The study was carried out in three replicates using the randomized block method. As a result of growing turnips, it was found that at early sowing dates (the second and third decades of April), the germination period is shorter, and at sowing seeds at later dates, the germination period is extended and ranges from 8 to 9 days. When sowing turnip seeds in the third decade of April, there is a more active growth of root crops; when sowing in the first and second decades of May, active plant growth and root crop development are observed; when sowing seeds in the third decade of May, better development of the leaf surface is established. The largest mass of root crops is characterized by the turnip variety Purpulepop (388.3 g) when sowing seeds in the second decade of April. The optimal seed sowing date, which contributes to obtaining a higher yield of turnips, is the second and third decades of April, where the value can vary from 23.8 t/ha to 24.9 t/ha of root crops. When sowing seeds in the first and third decades of May, the yield of turnip roots decreases. The highest yield of root crops is characterized by the turnip variety Purpulepop 24.9 t/ha and 24.6 t/ha, which exceeds the yield of the Zolota Kulya variety by 1.5 and 1.2 t/ha, respectively. The highest dry matter content is possible when sowing seeds in the first decade of May for all turnip varieties - (18.89 − 19.51 %), with the varieties Purpurova (19.51 %) and Geisha (18.89 %) standing out; the highest sugar content (10.66 and 11.34%) or an increase of 2.88 % and 2.2 % is possible for early sowing dates (second and third decades of April) for the Purpurova variety; an increase in protein content by 12% is possible for the Zolota Kulya variety when sowing seeds in the third decade of April, and an approximate value is characterized by the Purpulepop varieties (6.63%) when sowing seeds in the second decade of May and the Purpurova variety - 6.61% (third decade of April); vitamin C in root crops can increase by 7-10% for the Purpulepop and Purpurova varieties, the seeds of which should be sown in the second-third decade of April and the first decade of May.

In order to study the effect of the time of sowing seeds on the passage of morphogenesis and productivity of rapeseed, the scheme included experiments where the seeds were sown in I, II, III in April, I and II in May. The experiment used varieties of Golden Ball, Purpurleopop, Purpurov and Geisha, and control was the variant in which the seeds of the Golden Ball varieties were sown in the second decade of April with a row spacing of 45 cm. laboratory - to determine the total yield; statistical - to establish the reliability of the investigated factors. Seed germination analysis used in the experiment ranged from 78.9% to 81.1% on average. The highest indicator of seed germination was characterized by the Purpulepop variety, where the studied value was 83.2%, which was dominated by the seed germination of the control variant by 2.1%. In the early stages of sowing seeds, the period of seedling formation was shorter. Seeding of seeds in the first two decades of April on the surface of the soil was observed for 8 days. The short sprouting period was characterized by all varieties of turnips. As a result of sowing turnip seeds at a later date, namely in the third decade of April - the first and second decade of May and the setting of a higher soil temperature, the period of germination was extended and ranged from 8 to 10 days. By using the term of sowing seeds I-II decade of April, the short interphase period was characterized by Purpleupop and Purpurova varieties, where the specified period was only 22 days. The sowing of turnip seeds at a later date ensured the formation of an interphase period of "seedlings - leaf rosette" in 23-25 days except Purpulopop variety. The interphase period "leaf rosette - the beginning of rooting" and "the beginning of rooting - technical maturity" determined the benefits of early seeding, namely in the first decade of April on varieties Purpulopop and Purpurov.The short vegetation period was characterized by the Golden Ball plants for sowing seeds in the first and third decades of April and the first of May. During the specified seeding period the duration of the growing season was only 40 days. A longer vegetation period was characterized by plants of the Geisha variety for sowing seeds in the first two decades of April. As a result of the use of the researched elements of technology to grow turnips in open soil, the total yield varied from 11.0 t / ha to 24.0 t / ha. The most productive is the first sowing of rapeseed, where its value ranged from 20.6 t / ha to 22.7 t / ha. At the same time, when sowing seeds in the first decade of April, the yield of turnip varieties Purpulepop was the highest and was 22.7 t / ha, or the increase was 2.4 t / ha.

Rising temperatures are already affecting fruit production, and phenological data are important in examining the agroclimatic conditions of the area. The research aims to analyse climate indicators for the sustainability of apple (Malus domestica, L.) production in Slovakia – the onset of the phenological phase of full flowering (BBCH 65) in 1931–2020, the occurrence of frost days in 1961–2020, and the analysis of the area and yield of apple trees in 2014–2022. The results show that in 1931–1960, full flowering began in the third decade of April (western Slovakia – April 24) and in the first decade of May (eastern Slovakia – May 3). On the contrary, over the past 30 years, the average onset begins already in the second decade of April (western Slovakia – April 18) and in the last decade of April (eastern Slovakia – April 25). This also caused a higher probability of frosts occurring between the 1st and 10th day after the onset of the BBCH 65 phase (Piešťany station – up to 137%), and thus a greater risk of flower damage. Due to climatic and economic factors, the total area of orchards is decreasing, but this is also related to the decrease in fruit harvest in Slovakia.

This study, conducted in the period 2006-2008, involved an evaluation of yield and commercially useful traits of red cabbage grown from seedlings produced from seeds sown at three different times (the second decade of April, the third decade of April, and the first decade of May). Seedlings were produced in multicell trays in an unheated greenhouse and in a nursery bed from seeds sown at the same time. The experiment included 6 red cabbage cultivars (‘Huzaro F<sub>1</sub>’, ‘Kalibos’, ‘Langedijker Polana’, ‘Rodeo F<sub>1</sub>’, ‘Roxy F<sub>1</sub>’, ‘Zelox F<sub>1</sub>’). After cabbage heads were harvested in the second decade of October (in each year), total and marketable yield as well as head weight and the head shape index were determined. Red cabbage yield was shown to be significantly dependent on the cultivar, time of sowing, and method of seedling production. Among the cultivars studied, the following proved to be the most productive, irrespective of the other experimental factors: ‘Zelox F<sub>1</sub>’ (marketable yield averaged 398.11 kg×100 m<sup>-2</sup>), ‘Roxy F<sub>1</sub>’ (marketable yield averaged 368.82 kg×100 m<sup>-2</sup>), and ‘Rodeo F<sub>1</sub>’ (marketable yield averaged 331.59 kg×100 m<sup>-2</sup>). The cultivar ‘Kalibos’ was characterized by the lowest marketable yield (on average 257.09 kg×100 m<sup>-2</sup>). Delayed sowing (to produce seedlings) by 10 and 20 days, compared to the earliest sowing time, had a significant effect on the reduction in total and marketable yield. Irrespective of the time of sowing, the production of seedlings in multicell trays did not have a significant effect on higher head weight. But the influence of the cultivar was significant - heads of the highest weight were found in the yield of the cultivar ‘Zelox F<sub>1</sub>’ (head weight was on average 1.71 kg). The head shape index was more than 1 and on average it did not exceed 1.35. The cultivar ‘Kalibos’ had the most elongated heads (with a conical shape), while cabbage heads in the cultivar ‘Langedijker Polana’ were closest to the spherical shape.

The results of studying the biological characteristics and ornamental qualities of annual ornamental plants from the families Brassicaceae, Caryophyllaceae, Hydrophyllaceae and Tropaeolaceae during spring sowing in the ground are presented. The research was carried out in the conditions of the continental climate of the forest-steppe of Western Siberia. The work used experimental methods-phenological observations and descriptions of ontogenetic states and theoretical research methods - analysis of phenospectres in comparison with hydrothermal conditions of vegetation periods, digital image processing of objects using a Carl Zeiss Stereo Discovery V12 stereomicroscope with an AxioCam MRc-5 digital camera, mathematical statistics. Agricultural techniques for row and nest sowing are described. It is determined that the soil readiness for sowing ornamental annuals is influenced by the hydrothermal conditions of the third decade of April - the first decade of May, and the conditions of the third decade of May affect the state of seedlings. Warm, dry weather from mid-August to mid-September is the most favorable for the ripening of fruits and seeds, as well as their gathering. A template of phenospectres has been developed to form a phenotheca for training specialists in the field of decorative plant growing and landscape architecture. A digital seed library of annual ornamental plant species has been created, which is used in practical classes at the Novosibirsk State Agrarian University (NGAU) and the Novosibirsk State University of Architecture, Design and Arts (NGUADI). Descriptions of biological features and ornamental qualities, as well as the main morphometric parameters of 12 species of beautifully flowering annual plants are given.

The aim of the study is to investigate the growth and development characteristics, economically valuable traits of Platycodon grandiflorus A. DC in the Non-Chernozem zone of Russia. The studies were conducted on the experimental field of the Botanical Garden of the Federal State Budgetary Scientific Institution VILAR in 2020–2023. The soils of the site are sod-podzolic heavy loamy. Sowing was carried out in the middle of the first - end of the second decade of May to a depth of 1–2 cm, with a row spacing of 60 cm and a seeding rate of 1.2 g/m2. The plot size was 2.4 m2, repeated 4 times. Phenological observations, biometric measurements, determination of raw material productivity, raw material yield were carried out according to the methodology adopted for the introduction of medicinal plants. The content of water- and alcohol-soluble extractive substances was determined according to the Hong Kong and Chinese Pharmacopoeias. In the conditions of the Non-Chernozem zone of Russia, the large-flowered bellflower goes through all phenological phases. Seedlings begin to appear 20–28 days after sowing. Plants in the first year of life finish vegetation in mid- to late October at a height of 2.04–15.6 cm with 5.2–12.8 true leaves. In plants of the 2nd–3rd year of life, the beginning of spring regrowth of the aboveground part is observed at the end of the third decade of April – first decade of May. The onset of mass budding is noted from July 28 to August 17, mass flowering is observed from August 11 to September 14 and continues until the end of September. Fruiting is observed from the first–second decade of September until mid–to late October. The duration of the vegetation period from the beginning of spring regrowth until the death of the aboveground part is 164–178 days. The yield of freshly harvested roots is (0.870 ± 0.091) kg/m2 for plants of the 2nd year of life, (2.286 ± 0.243) kg/m2 for plants of the 3rd year of life. The content of water- and alcohol-soluble extractive substances in the roots meets the requirements of regulatory documentation (Pharmacopoeias of Hong Kong and the People's Republic of China).

Goal. To monitor the phytosanitary condition of onion crops in the Right-Bank Forest-Steppe of Ukraine and to establish the species composition of dominant pests.
 Methods. The research was carried out in accordance with the generally accepted methodological recommendations in entomology.
 Results. As a result of long-term monitoring of onion crops, 12 species of phytophages from the ranks of Coleoptera — 46.2%, Lepidoptera — 23.1%, Diptera — 15.4%, Thysanoptera — 10.4%, Orthoptera — 5.0% and others. In the phase of leaf development (main shoot) (ВВСН 1—19) the most harmful are soil-dwelling pests: larvae of Agriotes sputator L. and Agriotes lineatus L.; larvae of the Melolontha melolontha L., the Melolontha hippocastani F), the Amphimallon solstitialis L.; Scotia segetum Schiff. and Gryllotalpa gryllotalpa L. In the phase of the beginning of thickening of the base of the leaves — bulb formation (ВВСН 41—43) phytophages dominate: onion fly (Delia antique Mg.), onion trips (Trips tabaci Lind.), Ceuthorrhynchus jakovlevi Schulzer.
 Conclusions. It was studied that with the number of soil pests 1.5—2.8 specimens/m2, plant damage is 24.6—28.3%, which is the reason for the liquefaction of crop density. It has been established that significant damage to onion crops is caused by the onion fly (Delia antique Mg.), the period of harmfulness of which lasts throughout the growing season. During the years of research, the flight of the phytophagous adult took place in the third decade of April — first decade of May, at the sum of active CAT temperatures (> 5°C) = 104—131°С. Mass flight of the pest was observed in the II—III decades of May, at an average daily air temperature of 12.8—17.4°C.

The article describes the results of a three-year field experiment studying the effects of sowing periods on the crop structure, biometric indicators and productivity of white lupine varieties Degas and Gamma. The experiment was conducted in 2015-2017 on the leached chernozem of the experimental field of Kurgan State Agricultural Academy in the forest-steppe zone of Kurgan Region. The first sowing period corresponded to the physical soil maturity (the third decade of April - the first decade of May), the subsequent sowing periods were 6-8 days after the first one. Only in 2015, the full ripeness phase was not achieved (the third sowing period). The optimal sowing period was the first one: the yield of lupine grain varied from 2.5 to 14.9 t/ha.

Uroleucon cichorii (Insecta: Hemipteroidea: Rhynchota: Sternorrhyncha: Aphididae) is an invasive alien species in the fauna of Belarus. In 1854 the species has been described by C. L. Koch from Germany. For the first time U. cichorii has been noted in Great Britain in 1876, in Estonia – 1894, in Romania – 1896, in Italy – 1900, in Belgium – 1901, in Crimea – 1903, in Latvia – 1924, in Poland –1930, in Netherlands – 1939, in Finland – 1941, in Ukraine – 1945, in France – 1948, in Sweden – 1949, in Norway – 1953, in Denmark – 1954, in Moldavia – 1955, in Austria – 1956, in Czech – 1958, in Hungary – 1959, in Bulgaria – 1960, in European Russia – 1962–1964, in Bosnia and Herzegovina – 1963, in Serbia – 1963, in Lithuania – 1963–1980, in Macedonia – 1964, in Switzerland – 1967, in Spain – 1971, in Sicily –1973, in Corsica – 1973, in Balearic Islands (Mallorca) – 1982, in Belarus – 1986 and Greece – after 1992. It is obvious that this chronological list describes a history of aphidological research rather than spreading of the invider across the European regions. As considered, the species has Mediterranean origin. Outside of Europe the species is known from Near East as well as Central Asia, Korea and North America. As host plants U. cichorii s.str. uses common chicory (Cichorium intibus L.) and related species of Cichorieae (Asteraceae). The species is known as a pest of common chicory (including leaf chicory) and endive. For the first time U. cichorii has been registered in 1986. At present the species is common for C. intibus growing on roadsides and in other ruderal biotopes. During 1986–2018 U. cichorii has been registered in the all regions of the Republic of Belarus. The map of geographic points of registrations is given. It is obvious that the invider’s expansion in the regions of Belarus is finished. The species is holocyclic and monoecious. Feeding on forage plants contributes to the loss of a significant amount of plastic substances, which leads to their dehydration and slow growth, and, as a result, a slight deformation of the stem. U. cichorii does not initiate the deformation of leaf blades and the premature dying off of the inflorescences, and also does not lead to the formation of galls. Perennial data show the appearance of fundatrices from overwintering eggs in the third decade of April – the first decade of May. Further a series of successive parthenogenetic generations and the growth of colonies occur. The winged females are recorded in July–August. The appearance of winged males and normal females occurs in September – the first decade of October. The eggs are deposited in the end of October. The largest peak in the number of U. cichorii registrations occurs in July–August.

The analysis of the results of phenological observations on 7 phases, which reflect the main moments of seasonal development of plants, was carried out: 1 – the beginning of vegetation, which is characterized by budding and appearance of a cone of leaves; 2 – from the end of the growing season until the phase of massive leaf fall; 3 – the beginning of shooting; 4 – the end of shoot formation; 5 – the beginning of flowering; 6– flowering completion; 7 – massive ripening of fruits. To compare the rhythm of introducers’ development in the new conditions, the European Forsythia, as the most adapted to our conditions variety, was chosen. It was established that under our conditions the vegetation period of Forsythias begins at the late March – early April, when the average daily temperature does not exceed +4 0C, that is, at the general period of vegetation beginning of woody plants. Most of the varietie sunder study start their vegetation by April, 3, when, according to the long-termaverage data, the growing season usually begins. The sum of positive temperatures above 0 0C during this period ranges from 3.2 to 17 0C. Forsythia Ovata begins to vegetate a bit later. As a result of the research, we have determined that at Forsythias under study the shoot formation began in the third decade of April – the first decade of May. This corresponds to the11.5-18.7 0C average air temperature, with a 25.6-29.8 0C sum of active temperatures above zero. According to duration of the period of shooting and its completion, we have attributed the studied Forsythias to the group with a short (up to 115 days) growth period. According to our observations, in Vinnytsia the flowering periods of Forsythia lasts averagely for 13-15 days. The shortest flowering period – 13 days – was observed at the Forsythia Ovata. The period of fruit formation in the studied Forsythia varieties is rather short (from 18 to 32 days) and depends on the sum of temperatures, terms of the variety flowering, its geographical origin and systematic position. As a result of the conducted observations, 30% of the annual shoots tips of the Forsythia Suspensa (up to 10-15 cm) were found damaged, but this did not cause a loss of decorativeness, since this species has a high growth rate (50-90 cm), thus there is no reason to claim its complete winter intolerance and low perspectives for its growing. Forsythia Ovata was not bitten by the frost, annual shoots of Forsythia Europaea was slightly frostbite during the frosts at the end of March 2019 at the level of 15% (5-6 cm). Study of the given species showed that all the Forsythia plants introduced in the territory of the VNAU biostationary show regular growth of shoots, satisfactory level of winter hardiness, formation of seeds capableof germination in Vinnytsia conditions (F. Sus. var. Sieboldii, F. Sus. var. Fortunei). Key words: biostationary, botanical garden, forsythia, tolerance, vegetation period, acclimatization, winter hardiness, drought resistance.

Uroleucon cichorii (Insecta: Hemipteroidea: Rhynchota: Sternorrhyncha: Aphididae) is an invasive alien species in the fauna of Belarus. In 1854 the species has been described by C. L. Koch from Germany. For the first time U. cichorii has been noted in Great Britain in 1876, in Estonia – 1894, in Romania – 1896, in Italy – 1900, in Belgium – 1901, in Crimea – 1903, in Latvia – 1924, in Poland –1930, in Netherlands – 1939, in Finland – 1941, in Ukraine – 1945, in France – 1948, in Sweden – 1949, in Norway – 1953, in Denmark – 1954, in Moldavia – 1955, in Austria – 1956, in Czech – 1958, in Hungary – 1959, in Bulgaria – 1960, in European Russia – 1962–1964, in Bosnia and Herzegovina – 1963, in Serbia – 1963, in Lithuania – 1963–1980, in Macedonia – 1964, in Switzerland – 1967, in Spain – 1971, in Sicily –1973, in Corsica – 1973, in Balearic Islands (Mallorca) – 1982, in Belarus – 1986 and Greece – after 1992. It is obvious that this chronological list describes a history of aphidological research rather than spreading of the invider across the European regions. As considered, the species has Mediterranean origin. Outside of Europe the species is known from Near East as well as Central Asia, Korea and North America. As host plants U. cichorii s.str. uses common chicory (Cichorium intibus L.) and related species of Cichorieae (Asteraceae). The species is known as a pest of common chicory (including leaf chicory) and endive. For the first time U. cichorii has been registered in 1986. At present the species is common for C. intibus growing on roadsides and in other ruderal biotopes. During 1986–2018 U. cichorii has been registered in the all regions of the Republic of Belarus. The map of geographic points of registrations is given. It is obvious that the invider’s expansion in the regions of Belarus is finished. The species is holocyclic and monoecious. Feeding on forage plants contributes to the loss of a significant amount of plastic substances, which leads to their dehydration and slow growth, and, as a result, a slight deformation of the stem. U. cichorii does not initiate the deformation of leaf blades and the premature dying off of the inflorescences, and also does not lead to the formation of galls. Perennial data show the appearance of fundatrices from overwintering eggs in the third decade of April – the first decade of May. Further a series of successive parthenogenetic generations and the growth of colonies occur. The winged females are recorded in July–August. The appearance of winged males and normal females occurs in September – the first decade of October. The eggs are deposited in the end of October. The largest peak in the number of U. cichorii registrations occurs in July–August.

Goal. The effectiveness of the herbicides Hurricane Forte 500 SL, RK and Bast 150 SL, RK in protecting the apple orchard from ragweed was evaluated.
 Methods. The studies were conducted in the field in plantations of apple trees. The soil of the experimental plot is the southern light loamy chernozem, with a humus content in the arable layer of 3.2%, pH — 7.1. The tree planting scheme was 1.5—4 m. The experiments, observations, and counting were carried out according to generally accepted methods.
 Results. According to the results of phytosanitary surveys of apple plantations in farms of Odessa region, 27 species of weeds were identified, which belong to 12 botanical families. Among the annual weeds, the following species dominated: ragweed, ragweed, common shrubbery, common bedroot, white gauze; from perennial species: sharp gusset, pink sow thistle, field bindweed, wheat grass creeping, spurge vine. The mass emergence of seedlings of ragweed was observed in the third decade of April — the first decade of May. The phase of development of ragweed plants at the time of processing was 2—4 true leaves. Herbicide Hurricane Forte 500 SL in the norm of 2.0 l/ ha a month after treatment controlled 98.0%, at the end of the growing season — 83.2% of the weed. The treatment of plots with Hurricane Forte 500 SL with a flow rate of 1.0 l/ha and the addition of Trend 90 surfactant to the working solution ensured weed control after a month — 96.8%, at the end of the growing season — 80.6%. With a single application of the Bast 150 SL herbicide at a consumption rate of 4.0 l/ha, the technical efficiency a month after treatment was 94.7%; at the end of the growing season, it decreased to 60.1% due to the regrowth of ragweed plants. Two-time use of the Basta 150 SL preparation at a consumption rate of 3.0 l/ha made it possible to control the weed during the entire growing season at the level of 86.4—87.4%.
 Conclusions. The use of a reduced consumption rate of the Hurricane Forte 500 SL, RK herbicide in a mixture with the surfactant Trend 90 provides control of the ragweed at the optimal rate. Herbicide Basta 150 SL, RK is more effective to apply twice.

The cockhafer (Melolontha melolontha L.) is the most widespread and best known bug. It is a polyphagous bug, being harmful both in adulthood and in larva stage. The researches were conducted at Agricultural Research and Development Station (A.R.D.S.) of Secuieni, Neamţ county, Romania, and followed the evolution of adult flight, during 1993 - 2012 with a light trap help. The gatherings and records were made daily from 1 April to 31 October every year, during the observation period. Dividing the observation period into four stages of five years each, it was found that the largest number of specimens, 38059, was collected in the second stage (1998 - 2002), followed by the third stage (2003 - 2007) with 18167 specimens, first stage with 12173 specimens, and the lowest number of 286 specimens was recorded in the fourth stage (2008 - 2012). The adults flight started in all the years in the second or the third decade of April and lasted until the second or the third decade of May, with the exception of 1995 şi 2009 when he finished in the first decade of June. The average duration of the flight was 39 days. The maximum flight curve was reached, in all years of observation, in the third decade of April and first decade of May. The maximum intensity of flight curves was recorded every three years, as follows: 1994, 1997, 2000, 2003, 2006, 2009, 2012. This shows that, in Secuieni conditions, the insect has one generation at 3 years. Highest intensity of flights has been in the years 2000, when the top flight was conducted by 38059 specimens, 2003 with 13912 specimens/flight and 1997 with 10221 specimens/flight.

The article presents the results of research on the influence of seed sowing dates on the energy productivity of grain sorghum and sorghum. Goal. Investigate the influence of seed sowing dates on the energy productivity of grain sorghum and varieties of Dniprovsky 39 and Samaran 6 varieties in the conditions of the eastern part of the Forest-Steppe of Ukraine. Methods. The field method was used in the study, which includes the study of biological and ecological features of growth and development, productivity and quality of the studied crop; laboratory method used to study the relationship between plant and environment; mathematical and statistical methods included the processing of experimental data to increase the validity of conclusions. Results. High yields of sorghum grain and biomass were obtained during sowing of seeds in the first decade of May (second sowing period), when the soil temperature at a depth of 10 cm was 12-14 оС. In grain sorghum of Dniprovskyi 39 and Samaran 6, grain yield was 7.1 and 6.4 t/ha, biomass – 37.4 and 35.9 t/ha. The highest yield of bioethanol and solid fuel was obtained in the same variant of the experiment. The highest energy yield was obtained for sowing seeds in the first decade of May and was equal to 199.3 GJ/ha in the variety Dniprovsky 39 and 187.9 GJ/ha in the variety Samaran 6. About 71.0-72.0 % are concentrated in solid fuel (140,8 and 135.2 GJ/ha) of this energy and in bioethanol only 28-29 % (51.1 and 52.7 GJ/ha). Conclusions. It was studied that the grain yield and biomass of sorghum and sorghum mostly depend on the terms of sowing seeds – 29.2 %, the degree of influence of varieties was much lower and amounted to 8.1%. It is established that in comparison with the optimal sowing dates – the first and second decades of May, sowing seeds in the third decade of April (I sowing period) reduces grain yield by 4.2-12.6 % in the variety Dniprovsky 39 and 4.7-9,4 % in the variety Samaran 6; aboveground mass by 4.8-9.6 % and 6.4-10.6 %, respectively. Correlation-regression analysis of the data shows a close relationship between yield and biofuel yield. The correlation coefficient was R = 1, the coefficient of determination R2 = 1. There is also a strong correlation between yield and energy yield where R = 1, the coefficient of determination R2 = 1. Key words: varieties, yield, yield of biethanol and solid fuel, energy yield.

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.