Ponto-Caspian Research Articles

Features of Forming Soil Regimes under Sunflower Cultivation with Different Levels of Biologization in Non-irrigated Conditions of the Southern Steppe of Ukraine

Features of Forming Soil Regimes under Sunflower Cultivation with Different Levels of Biologization in Non-irrigated Conditions of the Southern Steppe of Ukraine

The effect of the biopreparation Avatar-2 Zahyst application on seed potato productivity and viral diseases infestation in condition of southwestern Forest Steppe part of Ukraine

Goal. To establish the effect of a multicomponent preparation of biologic origin on seed potato productivity and viral diseases infestation in condition of southwestern Forest Steppe of Ukraine.
 Methods. Field method — the trial plots were set in selection-seed production rotation of Bukovinian state agricultural research station of Carpathian region Institute of agriculture NAAS. Laboratory-field method — determining crop capacity and tubers structure in a yield. Visual method — plants infestation assessment. Comparative-calculated method — to determine the potato stands productivity and viral diseases infestation degree.
 Results. Avatar-2 Zahyst is a system-contact preparation of virulicidal, fungicidal, and antibacterial action. It is recommended for use on grain, technical, vegetable-, and fruit crops. The preparation is used for pre-sowing seed treatment, as well as for vegetating plants treatment. When determining the seed potato productivity depending on the biopreparation Avatar-2 Zahyst implementation, no significant difference in tubers yield was established; on the variety Slauta it stayed within 34.5—36.3 t/ hа, and on the variety Kimmeria 36.7—37.4 t/ hа. No any significant difference was established also in quantity and tubers mass per one bush, as well as in one tuber average mass, and tubers fractional composition in a harvest. When determining plants infestation with viral diseases, it was established, that the biopreparation Avatar 2 Zahyst application has influenced the decrease of seed potato stands infestation. The variety Slauta damage on the variant with seed poisoning and three-times spraying during vegetation made 2.5%, which is by 2—3% lower than on the control variant. The infestation of plants where only seed poisoning was implemented made 3—4%, when of those where three-times preparation application was carried out during vegetation — 2.0—4.0%, which is by 0.5—2.5 and 1.5—2.5% lower than the control variant, respectively. The same tendency was observed during the variety Kimmeria investigation.
 Conclusions. The use of the biological product Avatar-2 Zahyst does not give a significant difference in the yield of tubers. The introduction of the biological product Avatar 2 Zahyst influenced the reduction of the incidence of viral diseases in potato seed plantations.

Efficiency of the application of biological systems of the protection of apple trees against powdy dew and scamb in the conditions of the Western Forest-Steppe of Ukraine

Goal. To study the effectiveness of different biological systems of apple tree protection against scab and powdery mildew in the Western Forest-Steppe of Ukraine.
 Methods. Phytosanitary monitoring was carried out visually and with the help of pheromone traps. Accounting of the spread and development of diseases was carried out according to generally accepted methods in the phases of apple tree development: «bud swelling», «green cone», «bud extension», «bud separation», «pink bud», «flowering», «end of flowering», «fruit formation», «fruit growth» and «fruit ripening». The technical effectiveness of fungicides was determined after 7 days. Statistical processing of the research results was carried out according to generally accepted methods.
 Results. The results of monitoring the phytosanitary state of apple plantations established that the most common diseases in 2021—2022 in the conditions of the Western Forest Steppe of Ukraine were scab, which affected 15—29% of leaves and 8—13% of apple fruits, powdery mildew, which affected 15—18% of leaves of apple trees, moniliosis, the prevalence of which was 9—13%, and fruit rot, which affected 13—14% of apple fruits. The research results showed that the use of the biological protection system No. 1 (Fluorescin BT, Bactophyt BT, BioHybervit BT, Trihopsin BT, Fluorescin BT) made it possible to reduce the development of powdery mildew by 59.0%, and to reduce the development of scab on leaves and by 59.1%, 62.2% — scab on apple fruits. The use of biological protection system No. 2 (Bactophyt BT + Trihopsin BT, BioHybervit BT, Fluorescin BT, Trihopsin BT, Fluorescin BT) made it possible to reduce the development of powdery mildew by 43.6%, by 47.7% to reduce the development of leaf scab and by 48.6% — scab on apple fruits. The use of biological protection system No. 3 (Ampelomycin BT + Bactophyt BT, Phytosporin + Fluorescin BT, BioGibervit BT, Biospectr BT, Trihopsin BT + Fluorescin BT) made it possible to reduce the development of powdery mildew by 53.8%, and to reduce the development of scab by 68.2% leaves and 67.6% — scab on apple fruits. Using the studied biological systems to protect apple trees from scab and powdery mildew in the conditions of the Western Forest-Steppe of Ukraine yield indicators of 13.2—13.8 t/ha were obtained. The use of the studied biological protection systems made it possible to obtain from 2946 to 8526 UAH/ha of conditional net income and profitability indicators from 72.7 to 229.4%.
 Conclusions. The results of the research established that all investigated systems of biological protection of apple trees against scab and powdery mildew in the conditions of the Western Forest Steppe of Ukraine made it possible to protect apple plantations at a reliable level and obtain high yields. The technical efficiency of the applied protection systems against powdery mildew was 43.6—59.0%, against scab on apple leaves — 47.7—68.2%, and against scab on apple fruits — 48.6—67.6%. The yield for the application of the investigated biological systems of apple tree protection against scab and powdery mildew was 13.2—13.8 t/ha. Biological protection system No. 1 was the most effective in terms of profitability — 229.4%, and the highest indicator of conditional net income was obtained from the use of biological system No. 3 — UAH 8526/ha.

Organic fertilizers in increase of hazelnut yield

Goal. To assess the effect of various organic fertilizers on the yield of hazelnut plantations in the conditions of the Southern Steppe of Ukraine.
 Methods. Field experiment, laboratory-analytical, comparative.
 Results. The influence of organic fertilizers of various origins was studied (cattle manure; chicken droppings; Biofertilizer No. 1 — sewage sludge (SW) of the biological treatment station (SBO) «Pivdenna» in Odesa + winter wheat straw + Microbacterium barkeri LP-1 (M. b.); Biofertilizer No. 2 — «Southern» SBO + sunflower seed husks + M. b.; «Pivdenna» SBO, Odesa) on the agrochemical parameters of ordinary medium-humus chernozem in the conditions of the Southern Steppe of Ukraine for the cultivation of hazelnuts. It is shown that in comparison with the control of 2021 and 2022, an increase in the content of easily hydrolyzed nitrogen, mobile forms of phosphorus and potassium, and organic matter is noted in all variants of the experiment.
 Conclusions. The use of organic fertilizers of various origins for the cultivation of hazelnuts in the conditions of the Southern Steppe of Ukraine helps to increase the content of the main agrochemical indicators of the soil — easily hydrolyzed nitrogen (91.0—98.0 mg/kg with 84.0 mg/kg — control), mobile phosphorus compounds (174.75—306.30 mg/kg at 138.75 mg/kg — control), potassium (112.00—166.90 mg/kg at 108.40 mg/kg — control) and organic matter (3.78—4.18% and 3.76% — control). The advantages of biofertilizers No. 1 and No. 2 based on sewage sludge with the use of vegetable fillers (winter wheat straw and sunflower seed husks) and the phosphate-mobilizing bacterium Microbacterium barkeri LP-1 are shown. Organic fertilizers contribute to the increase in the content of nutrients in the soil, the activation of the activity of eco-trophic groups of microorganisms, which leads to an increase in the biological activity of the soil and, accordingly, the yield of agricultural crops.

Efficiency of application of the complex based on pseudomonas fluorescens bacteria on potato plantations in the Western Forest Steppe of Ukraine

Goal. To form effective complexes based upon bacterium Pseudomonas fluorenscens in combination with stimulation growth preparations and microelements with their efficiency study on potato plantations.
 Methods. The researches conducted during 2021—2022 in breeding- seeding rotation on the base Ukrainian Research Plant Quarantine Station of Institute of Plant Protection of NAAS. The experiment conducted on variety Slovyanka. The preparations efficiency determined in different rates against fungi diseases. Records conducted as per generally approved techniques with experimental methods in plant pathology and plant protection.
 Results. The efficiency of complex based upon Pseudomonas fluorescens АР-33 with stimulating matter nature and chelated microelementson potato plantations in growing period. The yield increased in 1.1—1.5 times during chelate 1 adding to preparation based upon bacterium Pseudomonas fluоrescens, and it increased in 1.3—1.6 times during chelate 2 addition. All biocomplexes combinations showed the preparation efficiency against Alternaria blight in scope 41.5—66.8%, but for late blight it had the following indexes 65.6—85.2.
 Conclusions. Combinations with chelates № 2 (Fe + Mn + Zn + Mo + Co + B) provided best growing results and yield. The combination Pseudomonas fluоrescens + xymedon + accinic acid + DMAE2ml/l + DМSО2 ml/l chelate (3.6%) showed the best result against potato Alternaria blight. It’s efficiency consisted of 66.8%.The combination Pseudomonas fluоrescens + xymedon + accinic acid + DMAE2ml/l + DМSО2 ml/l chelate(3.6%) showed 85.2% against late blight. It was the best index.

Spread of dangerous walnut diseases in plantations of different ages in the Western Forest Steppe of Ukraine

Goal. To investigate the development of the phytopathogenic complex of walnut in the Western Forest Steppe of Ukraine.
 Methods. The research was carried out during 2021—2022 in the agrocenosis of the walnut garden of the Ukrainian Research Plant Quarantine Station of the Institute of Plant Protection of the National Academy of Sciences. For a detailed account of the disease, twenty trees were examined from four sides of the crown and 25 accounting organs (leaves, shoots, fruits) were analyzed and the intensity of their damage was determined according to the scale. Diagnosis of diseases was carried out by selecting affected tissues and placing them in a moist chamber for three days for subsequent identification of the type of pathogen by microscopy and determination of systematically important morphological features of the fungus. Isolation of fungi from living plants was carried out by transferring mycelia or spores from their surface to a new environment.
 Results. A laboratory study of plant material with various symptoms of damage showed the dominance of phytopathogenic fungi: brown spotting Marssonina juglandis (Lieh.) Magn., white spotting Microstroma juglandis Sacc. and bacteriosis Xanthomonas juglandis Sacc. When surveying old tree plantations (more than 40 years old), the frequency of brown spotting of walnut Marssonina juglandis (Lieh.) Magn. accounted for 68.7%, bacterial burn (Xanthomonas juglandis Sacc.) — 31.3%. In stands of 6-year-old trees, the frequency of brown spotting Marssonina juglandis (Lieh.) Magn. was 72.5% and bacterial burn Xanthomonas juglandis Sacc. — 27.5%. When inspecting the plantations in the nursery (trees 2—3 years old), the frequency of brown spotting of the walnut Marssonina juglandis (Lieh.) Magn. accounted for 80.3% of bacterial burn Xanthomonas juglandis Sacc. — 12.1%, white spot Microstroma juglandis Sacc. — 7.6%.
 Conclusions. During the examination of walnut plantations (in trees of different ages), it was found that the high incidence of diseases, in particular, brown spotting Marssonina juglandis (Lieh.) Magn. was noted in nurseries, where on the day of the last record on susceptible forms of culture, damage by brown spot was 100.0%, while the development of the disease was 47.7%.

Monitoring of the species composition and number of insects and mites on the apple trees in the Right Bank Forest Steppe of Ukraine

Goal. To monitor the species composition and abundance of insects and mites on apple trees in the Right-Bank Forest-Steppe of Ukraine.
 Methods. Field, laboratory, microscopic, mathematical, statistical and calculation methods. The research was carried out according to generally accepted methods in entomology and plant protection, starting in early spring (late April — early May before harvest).
 Results. Monitoring of the number of insect pests and mites on apple trees in three types of plantations was carried out: a young orchard on stunted rootstocks with an intensive protection system; an old orchard on tall rootstocks with a protection system; an old orchard without treatments (long-term control).
 Conclusions. Monitoring of species composition and dynamics of pests number makes it possible to study and substantiate the patterns in the structure of insect and mite populations, to predict their harmfulness and to improve the protection system of apple trees or its individual components.

Elevated genetic risk for multiple sclerosis emerged in steppe pastoralist populations

Multiple sclerosis (MS) is a neuro-inflammatory and neurodegenerative disease that is most prevalent in Northern Europe. Although it is known that inherited risk for MS is located within or in close proximity to immune-related genes, it is unknown when, where and how this genetic risk originated1. Here, by using a large ancient genome dataset from the Mesolithic period to the Bronze Age2, along with new Medieval and post-Medieval genomes, we show that the genetic risk for MS rose among pastoralists from the Pontic steppe and was brought into Europe by the Yamnaya-related migration approximately 5,000 years ago. We further show that these MS-associated immunogenetic variants underwent positive selection both within the steppe population and later in Europe, probably driven by pathogenic challenges coinciding with changes in diet, lifestyle and population density. This study highlights the critical importance of the Neolithic period and Bronze Age as determinants of modern immune responses and their subsequent effect on the risk of developing MS in a changing environment.

Water balance of winter wheat following different precursors on the Ukrainian steppe

ABSTRACT In the steppe zone of Ukraine during the growing season autumn 2021 through the beginning of summer 2022, water balancing in a winter wheat crop with peas as a precursor was 3–9 times greater than with a cereal (spring barley) or sunflower as a precursor; Normalized Difference Vegetation Index (NDVI) following peas was 1.6–1.7 times greater; the Normalized Difference Water Index (NDWI, the rate of moisture supply) in the plant leaf at the macro-stages BBCH 10–61 was 1.54–1.82 times higher; and productivity 1.43–1.56 times higher. Water consumption for the formation of a tonne of winter wheat grain following peas was one third less compared to other precursors.

BIOMETRIC PARAMETERS OF SAFFLOWER (CARTHAMUS TINCTORIUS L.) UNDER THE INFLUENCE ON SEEDING RATE AND ROW SPACING

The aim of the present work was to establish the peculiarities of the formation of biometric parameters of safflower varieties depending on the influence of the elements of cultivation technology – the seeding rate and the row spacing in the conditions of the Right Bank Forest Steppe of Ukraine. Methods. This study was conducted in the field of the Agronomic Research Station of the National University of Life and Environmental Sciences of Ukraine in the years 2021-2023 on typical low-humus soils. The scheme of the three-factor field experiment was made to study the influence of the following factors: factor A – varieties “Dobrynia” and “Soniachnyi”, factor B – row spacing: 19, 38 and 57 cm, factor C – seeding rate: 100, 200 and 300 thousand seeds/ha. Results. It is established that the row spacing of 19 cm and a seeding rate of 300 thousand seeds/ha contributed to the formation of a better height of safflower plants than on the variants with a row spacing of 38 and 57 cm, while the plants did not overgrow under such conditions. It was investigated that the number of heads was higher in both varieties with the row spacing of 38 cm, at the same time the average number of heads of the variety “Dobrynia” was made 20,2-22,2, and of the variety “Soniachnyi” – 19,2-22,1. The mass of 1000 seeds was higher with a row spacing of 57 cm, and for “Dodrynia” variety in average it was made 47,7 g, for “Soniachnyi” variety – 49,2 g. For “Dobrynia” variety the number of seeds per plant under the seeding rate of 100 thousand seeds/ha and row spacing of 19 cm was made 450,9 and for “Sonyachnyi” variety the number of seeds per plant under the seeding rate of 100 thousand seeds/ha and row spacing of 38 cm was made 455,4. On the same variants of the experiment, the seed weight per plant was made 20,6 and 21,1 g/plant, which corresponded to the best indicators in context of the variants. Conclusions. It has been studied that the formation of plant height, the number of heads and the mass of 1000 seeds is influenced by the row spacing in the range of 53.2-68.9%, and varietal peculiarities determine the limits of deviations of the characteristics by 13-29.8%. At the same time, the seeding rate had a slight effect on the studied indicators. In contrast to these characteristics, the number of seeds per plant and the weight of seeds per plant significantly depend on the seeding rate of safflower (at the level of 71.3-78.7%), while the row spacing affects only 14.6-22.6 %, and the variety has no significant effect on these parameters.

Photo Story: Spring brings hope to the Ukrainian steppes

Photo Story: Spring brings hope to the Ukrainian steppes

EVALUATION OF SEED YIELD AND THOUSAND SEED WEIGHT OF CONFECTIONERY SUNFLOWER (Helianthus annuus L.) VARIETIES GROWN BY DIFFERENT FARMING TECHNIQUES IN THE NORTHERN STEPPE OF UKRAINE

The paper presents data on the seed yield and thousand seed weight of confectionery sunflower (Helianthus annuus L.) varieties cultivated in the Northern Steppe of Ukraine. The study was conducted on three varieties-populations and one F1 hybrid. The study design included two types of basic tillage, three doses of fertilizer, and three plant densities. The seed yield significantly (P = 0.05) depended on the year of testing (the contribution of the year factor to the total variability was 38.88%), plant density (29.30%) and fertilizer dose (14.43%). It also depended on the tillage type (3.01%) and varietal characteristics (0.87%). The highest yield of seeds (up to 4.24 t/ha) was obtained with moldboard plowing, NPK fertilizer doses of 40:60:60 and 60:80:80 and plant density of 40,800 plants/ha. The thousand seed weight significantly (P=0.05) changed under the influence of the year of testing (32.11%), plant density (26.75%) and variety (25.92%), as well as under the influence of fertilization (3.24%) and tillage (3.75%). The largest thousand seed weight (up to 122.3 g) was obtained with moldboard plowing, NPK fertilizer doses of 40:60:60 and 60:80:80 and plant density of 20,400 plants/ha. Recommendations on the farming technique for confectionery sunflower have been drawn up.

Efficacy of insecticides against wheat thrips Haplothrips tritici Kurd. in winter wheat crops

Goal. To develop an effective system of winter wheat protection against wheat thrips Haplothrips tritici Kurd. Determine the technical effectiveness of insecticides Karate Zeon 050 CS, SC (lambda-cyhalothrin, 50 g/l); Match 050 ES, CE (lufenuron, 50 g/l); Enjio 247 SC, CS (thiamethoxam, 141 g/l + lambda-cyhalothrin, 106 g/l); Talstar, 10% CE (bifenthrin, 100 g/l); Mospilan, VP (acetamiprid, 200 g/kg); Inazuma, VG, (acetamiprid, 100 g/kg + lambda-cyhalothrin, 30 g/kg) in the Southern Steppe of Ukraine.
 Methods. The experiment was set up on winter wheat crops in 4-, 5- and 8 replications in 4x replication. The plots were arranged by the method of randomized blocks. The pest was counted by sampling 20 ears of wheat, which were placed in paper bags, tightly closed, delivered to the laboratory and counted live and dead adults by analyzing each ear for all samples from each experiment. Larvae were counted by the method of distillation using selectors.
 Results. To control the number of thrips, the effectiveness of the insecticide Engio 247 SC, CS at four application rates (0.05, 0.1, 0.15 and 0.2 l/ha) and Karate Zeon 050 CS, SC; Inazuma, VG; Match 050 ES, CE; Mospilan, VP; Talstar, 10% CE was studied. As a result of observations of changes in the number of thrips during 2017—2019, it was found that its appearance on winter wheat crops occurs from May 08 to 24. Peculiarities of weather conditions influenced the dynamics of thrips numbers. The duration of individual phases of wheat thrips development by years depending on the GTC was studied. The studies revealed the main patterns of wheat thrips population development and showed the possibility of controlling its number with the help of various insecticides.
 Conclusions. The use of insecticides Match 050 ES, CE; Karate Zeon 050 CS, SC; Talstar, 10% CE; Mospilan, VP; Inazuma, VG at consumption rates of 0.3 l/ha, 0.2, 0.1, 0.075, and 0.24 l/ha, respectively, on winter wheat crops against wheat thrips in the phase — «beginning of earing» (VVSN 51) effectively controls the number of thrips and provides technical efficiency of 93.7—96.1%. The use of the insecticide Engio 247 SC, KS at consumption rates of 0.05 l/ha, 0.1, 0.15 and 0.2 l/ha provides technical efficiency of this drug against pest larvae at the level of 90.2%, 94.7, 95.9 and 96.4%, respectively.

Peculiarities of the weed infestation of young paulownia (Paulownia tomentosa L.) stands

Goal. To study the weeding processes of young Paulownia tomentosa (Paulownia tomentosa L.) plantations for the further development of an effective weed protection system in the conditions of the Forest Steppe of Ukraine.
 Methods. To study the interaction of research objects with weather conditions, cultivation methods and technology, field methods (in particular, small-plot), as well as visual, measuring, weight, quantitative and physiological methods were used. The laboratory method was used to determine the quality characteristics of the soil of the experimental plots. Processing of experimental data was performed using the Microsoft Office Excel computer program.
 Results. It was established that young stands of paulownia in the first stages of vegetation are actually a free ecological niche, which is quickly filled by weeds. The largest number of weed species was from the Gramineae, Brassicaceae, and Asteraceae families. There was one species each from the Polygonaceae, Chenopodiaceae, Solanaceae, and Convolvulaceae families. In the second year of vegetation, the seedlings of Echinochloa crusgalli (L. Pal. Beauv), Chenopodium album L., Elymus repens (L.) Gould, Setaria glauca (L.) Pal. Beauv, Sinapis arvensis L., Polygonum convolvulus L., Thlaspi arvense L. On average, more weed seedlings were recorded during the accounting period than in the first year of crop vegetation.
 Conclusions. It has been experimentally proven that before establishing the plantations, the site should be evaluated for the presence of problematic weed species that can potentially multiply in paulownia plantations and interfere with effective plant care. The presence of weeds in young paulownia stands during the growing season leads to a significant suppression of culture plants. Establishing the features of the formation of weeding of paulownia plantations in the second year of vegetation is impossible without a comprehensive determination of plant growth parameters. Information about the specifics of weeding make it possible to correctly develop an effective system of protection against weeds.

Ecological plasticity and sustainability of cotton in the Southern Steppe of Ukraine

Depending on the length of the cotton growing season, the area of cultivation and its highest productivity potential are determined, and the prompt ripening of raw cotton allows for home-grown harvesting and high-quality soil preparation. The purpose of this study was to identify samples adapted to the conditions of the Southern Steppe of Ukraine from the cotton gene pool. The study used methods of plant variety expertise: phenological observations, morphological studies, and evaluation of breeding material for valuable traits. Based on the study results, parental components were selected to expand the process of forming early-ripening forms and productivity of raw cotton. The ability of cotton plants to grow in extreme conditions of the Southern Steppe of Ukraine was assessed and its homogeneity or stability, the index of growing conditions, the coefficient of variation – the difference in the numerical values of the trait duration of the period “germination – beginning of flowering” of plants in varieties with different growing season and their fluctuations around the average value were determined. It was found that according to the determined plasticity (bi), the variance of stability (Si2), and the coefficient of variation of the duration of “germination – the beginning of flowering” higher tolerance to environmental factors was characterised by ultra-early ripening varieties. The average regression coefficient (bi ) was -0.36; the variation in the duration of the period by year was 10.1%, which is significantly lower compared to early-ripening varieties – -0.77% and 12.9%, mid-ripening varieties – -0.80% and 15.0%, and late-ripening varieties – -1.30% and 16.6%, respectively. The maximum average productivity to frosty raw cotton of 49.4 g/plant was formed by the sample Pidozerskyi 4 (UF0800003), the duration of the period “germination – beginning of flowering” was 47 days, and “germination – full ripening” – <103 days. The lowest raw cotton productivity of 21.2 g/plant was demonstrated by the late-ripening sample Joloten 32 (IU14056549) of Turkmen selection, the duration of the growing season of which was 145 days on average over the years of research. The findings of this study will be used in further breeding to create high-yielding cotton varieties with increased environmental plasticity and stability and highquality fibre

Peculiarities of a confectionery sunflower cultivation technology

As of 2022, there are 22 names of confectionary sunflower in the State Register of Plant Varieties Suitable for Dissemination in Ukraine, accounting for almost 2% of the total number of cultivars and hybrids in the Register.
 Valuable economic characteristics of confectionery sunflowers are significantly affected by weather. In particular, 39% of the seed yield variability is determined by weather conditions; the thousand seed weight variability - by 32%; the huskness variability- by 26%; the  the 3.8+ fraction proportion variability - by 41%; and the protein content variability - by 12%.
 A review of literature on elements of the confectionary sunflower cultivation technology allowed us to identify major factors of the agricultural technology that affect such commercially important characteristics as yield and quality of seeds. These are basic tillage, optimal doses of mineral fertilizers, and plant density.
 An increase in plant density augments the yields of confectionary genotypes. However, in thin sowing (up to 20,000 plants/ha), the yield of the commercially important large fraction of seeds is raised. Manufacturers prefer cultivars and hybrids with both large thousand seed weights and economically profitable yields. Most researchers agree that seed size decreases as plant density is increased, and therefore it is desirable to aim for a plant density in the field that can produce sufficiently large seeds without significant reduction in the total yield. The best genotypes combine both yield a lot and have large thousand seed weights.
 Regarding the effects of basic tillage options on the confectionary sunflower yields, scientists' opinions are contradictory. In the southern steppe of Ukraine, the highest yield of confectionary sunflower seeds was harvested with moldboard plowing to a depth of 25-27 cm.
 A positive effect of nitrogen fertilizers at doses of 120-160 kg/ha on thousand seed weight was proven by numerous studies. However, one should take into account that excessive nitrogen extends growing periods, reduces resistance to diseases, and contributes to stronger negative reactions to arid conditions.
 Producers of confectionery seeds try to increase the yield of large seeds. Researchers report a high yield of large (4.5+) seed fraction, which in some cases can reach 83.6%. 3.8+ seed fraction is considered economically valuable. In the northern steppe, the yield of this fraction reached 81.4%, which was ensured by selection of genotypes, moldboard plowing, and thin sowing at a density of 20,400 plants/ha.
 Seed specific weight is influenced by many factors, in particular, weather, varietal characteristics, and farming techniques. Specific weight increases when crops are thickened.
 Therefore, the economic characteristics of confectionery sunflower genotypes vary widely due to varietal features and growing conditions (weather and climate, farming). Major elements of the confectionary sunflower cultivation technology are similar to those of the oil sunflower cultivation technology, but the former has certain peculiarities. High yields and desirable technological parameters of seeds are achieved via such farming factors as basic tillage, optimal doses of mineral fertilizers, plant density, and choice of a predecessor in crop rotation. The primary objective is to maintain economically profitable levels of seed yields in thin sowing, which is necessary to obtain large thousand seed weights. Particular attention is to be paid to studies of combined effects of farming techniques on the growth, development, and performance of confectionery sunflowers. Results of such comprehensive studies will allow for development of recommendations on the optimal application of farming techniques to reduce costs and raise the economic efficiency of confectionery sunflower cultivation.

Prediction of ctenophore Beroe ovata Bruguiere, 1789 habitat expansion and control of invading Mnemiopsis leidyi Agassiz, 1865 in the Ponto-Caspian basin associated with climate change

The seas of Ponto-Caspian basin (Black, Azov and Caspian) are exposed to species invasions, including harmful ctenophore Mnemiopsis leidyi A. Agassiz, 1865 and its predator Beroe ovata Bruguière, 1789. Current environmental conditions of invasive ctenophores M. leidyi and B. ovata occurrence, development and variability in the Ponto-Caspian basin have been compiled, based on own field observations and published data. Analysis of climatological data on basic environmental parameters (water temperature, salinity, chlorophyll concentration) and modeling approach were used to predict favourable for both ctenophores conditions, and changes of those conditions, associated with the climate variations. The role of B. ovata as a bio-controller of M. leidyi population has been assessed. Several climate change scenarios have been considered in this study i.e., uniform increase/decrease of SST throughout the year by 2 °C and only spring temperatures increase/decrease by 2 °C. The most sensitive to increase in SST in terms of M. leidyi reproduction duration are the western coast of the Black Sea and the Southern and Middle Caspian. On the other hand, B. ovata reproduction duration is expected to increase in several areas, including the northern coast of the Black Sea and the Southern and Middle Caspian. The coastal areas of the Black Sea and the transitional regions between the Southern and Middle Caspian are exposed to an earlier start of M. leidyi reproduction during warmer springs. Regarding B. ovata, the whole Black Sea is vulnerable to spring SST changes, but in the Caspian Sea B. ovata extends its reproduction duration only in the Middle Caspian during warmer springs. Since B. ovata consumes mostly M. leidyi, it is an important biocontrolling agent of M. leidyi, harmless for the ecosystem.

Formation of yield and seed quality of linseed varieties (Linum humile Mill.) in the conditions of the Western Forest Steppe of Ukraine

Purpose. To determine the peculiarities of yield and seed quality formation of varieties of linseed (Linum humile Mill.) in the conditions of the Western Forest Steppe of Ukraine. Methods. The research was conducted in 2020–2021 at the experimental field of the Khmelnytskyi branch of the Ukrainian Institute for Plant Varieties Examination (Trebukhivtsi village, Letychivskyi district, Khmelnytskyi region). Sowing was carried out in the second decade of April, the sowing rate was 8.0 million seeds per hectare. Subjects of the research were oil flax varieties ‘Orfei’, ‘Svitlozir’ and ‘Vodohrai’. The experimental design, evaluation of material, phenological observations and biometric measurements of plants, harvesting were carried out in accordance with the “Methodology for the qualification examination of plant varieties of the technical and fodder group for suitability for distribution in Ukraine”. The quality indicators of linseed were determined according to the “Methodology of qualification examination of plant varieties for suitability for distribution in Ukraine”. Results. The optimal conditions of the Western Forest Steppe of Ukraine contributed to the timely onset of the phenological phases of growth and development, as well as to the insignificant variation in the duration of the vegetation period (from 96 to 99 days) of the flax plants. Productivity was assessed using indicators such as the number of pods and the weight of seeds per plant. Under the condition of sowing on 25 April and the sowing rate of 8.0 million seeds per hectare, the highest yield was characterised by the variety “Svitlozir” (1.45 t/ha), the lo­west – ‘Orfei’ (0.8 t/ha). The varieties ‘Orfei’, ‘Svitlozir’ and ‘Vodohrai’ were evaluated by biochemical indicators and the content of crude protein, oil and fatty acids (palmitic, stearic, oleic, linoleic, linolenic, gondoic, eicosapentaenoic and erucic) was determined. Thus, ‘Orfei’ was characterised by the highest amount of protein in the seeds – 24.15%; ‘Svitlozir’ had an indicator of 22.74%; ‘Vodohrai’ – 22.26%. A high percentage of oil in the total dry matter was found in ‘Vodohrai’ – 45.6%, which is 2.19% more than in ‘Orfei’. The content of linolenic acid varied from 45.703 (‘Orfei’) to 48.261% (‘Svitlozir’) and erucic acid was not detected in any of the varieties during the study. Conclusions. The varieties ‘Orfei’, ‘Svitlozir’ and ‘Vodohrai’ were characterised by more than 35% oil content in seeds, which meets the requirements of State Standard 7577:2014 and ensures the quality of marketable oil flax products.

Formation of productivity of amaranth varieties in the Right Bank Forest Steppe of Ukraine under the influence of MaxiMarin absorbent

Purpose. To carry out an economic evaluation of amaranth varieties ‘Kharkivskyi­1’, ‘Helios’ and ‘Sem’ for the application of MaxiMarin absorbent used to compensate for lack of rainfall and uneven moisture in the forest steppe of Ukraine. Methods. During 2021–2023, three varieties of amaranth and MaxiMarin brand absorbent in the form of granules were studied in the field (Uman, 48°46¢N, 30°14¢E) at an application rate of 25 kg/ha. The varieties were evaluated according to the following parameters: weight of leaves, inflorescence and roots, yield of green mass in the flowering and full maturity phases. Amaranth grain yield, protein, fat and starch content were also determined. The methods of analysis of variance and correlation were used. Results. The absorbent applied had a significant effect on the productivity indicators, which were characterized by a significant difference between varieties. In particular, the average increase in the mass of leaves per plant for the studied varieties of amaranth was 12.2%, the mass of inflorescence – 8.9%, or 3.6 g/plant. The variety ‘Kharkivskyi­1’ responded best to the introduction of an absorbent that improved growth conditions, the weight of its inflorescence increased by 12.6%, or 5.3g/plant. The strengthening of growth processes was made possible by the improved deve­lopment of the root system and an increase in its mass, depending on the variety, of 12.3–24.6% (2.1–3.0 g/plant). At the same time, total plant weight increased by an average of 12.4% (11.2–13.3% in different varieties). Green mass yield increased by 13.6–16.5% (4.75–5.75 t/ha) due to the use of absorbent and was in the range of 33.0–40.0 t/ha. The highest values were characterized by the variety ‘Sem’ – 34.3 t/ha in the control and 40.0 t/ha in the experiments with added absorbent. Its application also caused an increase in the yield of different varieties of amaranth by 0.30–0.38 t/ha or 16.0–18.3% (the most productive was the variety ‘Sem’ – 2.08 and 2.46 t/ha, depending on the variant of the experiment) and a significant decrease in the concentration of protein (by 0.1–10.0%), fats (by 7.4–19.5%) and starch (by 3.2–8.2%). Conclusions. Absorbents are an effective tool for levelling moisture imbalances and ensuring maximum realization of the productive potential of amaranth, but improving the water regime has a negative effect on the accumulation of protein, fats and starch.

An individual with Sarmatian-related ancestry in Roman Britain

In the second century CE the Roman Empire had increasing contact with Sarmatians, nomadic Iranian speakers occupying an area stretching from the Pontic-Caspian steppe to the Carpathian mountains, both in the Caucasus and in the Danubian borders of the empire.1,2,3 In 175 CE, following their defeat in the Marcomannic Wars, emperor Marcus Aurelius drafted Sarmatian cavalry into Roman legions and deployed 5,500 Sarmatian soldiers to Britain, as recorded by contemporary historian Cassius Dio.4,5 Little is known about where the Sarmatian cavalry were stationed, and no individuals connected with this historically attested event have been identified to date, leaving its impact on Britain largely unknown. Here we document Caucasus- and Sarmatian-related ancestry in the whole genome of a Roman-period individual (126-228 calibrated [cal.] CE)-an outlier without traceable ancestry related to local populations in Britain-recovered from a farmstead site in present-day Cambridgeshire, UK. Stable isotopes support a life history of mobility during childhood. Although several scenarios are possible, the historical deployment of Sarmatians to Britain provides a parsimonious explanation for this individual's extraordinary life history. Regardless of the factors behind his migrations, these results highlight how long-range mobility facilitated by the Roman Empire impacted provincial locations outside of urban centers.