The value of biological fixation of air molecular nitrogen in the nitrogen feeding of agricultural crops and enrichment of soils is considered. High priority is paid to the economic and environmental significance of biological nitrogen. The state and prospects of the study of biological fixation of air nitrogen were analyzed; advantages of modern microbial nitrogen fixing preparations in comparison with nitrogen fertilizers have been proved.

Purpose.To study the soft winter wheat varietal material for frost and drought resistance increasing during further breeding practice. Methods. Wheat resistance to frost was evaluated by the methods of plant freezing in seed boxes (for sprouts), low temperature chambers (for seedlings) and drought tolerance by sprouting in sucrose solution with the intensity of the electrolyte’s leakage determination and the root system growth measurement. Results. The most frost-resistant in the seed boxes were the varieties ‘Trudivnytsia Myronivska’, ‘Rozkishna’, ‘Hordovyta’, ‘Kokhana’, ‘Zira’, ‘Tsarivna’ and ‘Charodiika bilotserkivska’. The high seedling frost resistance was typical of the varieties ‘Kalynova’, ‘Voloshkova’, ‘Remeslivna’, ‘Yuviliar Myronivskyi’, ‘Pamiati Remesla’, ‘Myronivska storichna’, ‘Favorytka’, ‘Bohdana’, ‘Yasnohirka’. Among the varieties from other breeding institutions were ‘Kokhana’, ‘Kraievyd’, ‘Romantyka’ and ‘Donsimb’. As a result of laboratory evaluation of soft winter wheat drought tolerance the highest percentage of seed germination in conditions of high osmotic pressure was common for varieties ‘Horlytsia Myronivska’, ‘MIP Kniazhna’, ‘MIP Valensiia’, ‘Statna’, ‘Hordovyta’, ‘Shchedra Nyva’, ‘Zira’. According to the intensity of the electrolyte’s leakage majority of varieties showed tolerance to the moisture deficit at phase VI of organogenesis. The most tolerant were varieties ‘Hordovyta’, ‘Benefis’, ‘Hospodynia Myronivska’, ‘Svitanok Myronivskyi’, ‘Berehynia myronivska’ and some others. Among the varieties of Myronivka breeding, according to the intensity of the root system growth, the varieties ‘MIP Valensiia’, ‘Hospodynia myronivska’, ‘Horlytsia myronivska’, ‘Podolianka’ were marked. Conclusions. The varieties ‘Trudivnytsia Myronivska’, ‘Roz­kishna’, ‘Hordovyta’, ‘Tsarivna’, ‘Charodiika Bilotserkivska’, ‘Zira’ were identified as of higher frost resistance. The varieties ‘Horlytsia Myronivska’, ‘MIP Kniazhna’, ‘MIP Valensiia’, ‘Podolianka’, ‘Statna’, ‘Rozkishna’, ‘Hordovyta’, ‘Shched­ra Nyva’, ‘Zira’ were found as of high drought tolerance. The varieties ‘MIP Kniazhna’, ‘Rozkishna’, ‘Hordovyta’ and ‘Zira’ were identified as of high complex adaptive ability.

Purpose is to create and evaluate the combining ability of the new output material of sodent plasma at the outlet of maize hybrids’ selection for steppe zone of Ukraine. Metods. Field, matematical and statistical. Results. In our study one of the main selection criteria was the evaluation of combining ability of the new output material by the main economic characteristics, which is of great importance for selection process assessment. The results of the evaluation of self-pollinated families S5 and S6 of sister hybrids created by crossing the early-maturing constant lines of the genetic plasma Iodent FAO 180–250 selection of the R&D Institute of Grain Crops of NAAS: ‘DK714/195’, ‘DK744’, ‘DK555’, ‘DK237’, ‘DK216’, ‘DK213’, ‘DK1274’ and ‘DK234’ were represented. It was shown the dynamics of the best self-pollinated families’ selection and the relations between the different genotypes’ reaction on growing conditions and the genetic origin of the output material were analyzed too. On the base of analysis of the yields of testcrosses, created with the best self-pollinated families, the hybrids with significantly higher crop standards were selected, with the less harvest corn moisture. For the economic evaluation of testcrosses, the yield index has been determined as the relation between the corn yield and corn harvest moisture. For the best testcrosses it was within 0.60–0.68 while the yield index value for the hybrids of standards was within 0.34–0.45. Conclusions. The early self-pollinated families S6 (DK744 ´ DK216)211111, (DK744 ´ DK213)111211 and (DK744 ´ DK555)112111 with higher estimated GCA effect on the basis of “grain yield” in comparison with the line standard ‘DK744’, were selected. It was determined the dependence of the GCA level of self-pollinated families on the genotype of the source lines, on the basis of which they were created. In particular, the most of the best self-pollinated S6 families include ‘DK744’ and ‘DK555’ lines

Purpose. To study the complex resistance of winter wheat collection using productivity index – total weight of all grains in one ear; drought and heat resistances; resistance to pathogens – powdery mildew, brown rust and pyrenophorosis (tan spot). To select plants with complex resistance for breeding programs aimed to create a high-yielding and highly adaptable source material. Methods. Field, laboratory and statistical. Results. The winter wheat varieties were divided into 3 groups according to the level of productivity and the way of use. They included 136 varieties, 33% of which were from Institute of Plant Physiology and Genetics, NAS of Ukraine (Kyiv breeding), 19% from the southern regions of Ukraine (south-Ukrainian breeding), and 42% from the foreign collection (West European breeding). On the basis of productivity, the highest priority in 69% belongs to Kyiv breeding varieties with grain weight within 3.1–4.0 g/ear. South-Ukrainian breeding varieties are of highest drought tolerance at the rank ‘medium-resistant’ – 25.0%, at the rank ‘higher than medium-resistant’ – 17.9% and ‘highly resistant’ – 10.7%. Varieties of Kyiv breeding have the highest percentage at the rank of ‘medium heat resistant’ and the ‘heat resistant’ – 25.5%. According to pathogenic resistance, Western European breeding varieties have the highest percentage of the resistance to powdery mildew and pyrenophorosis at the rank ‘higher than medium resistant’ – 43%. Varieties of Kyiv and south-Ukrainian breeding have the steadily medium resistance to diseases of three pathogens within 53–82 %. Conclusions. The sources of complex resistance of winter wheat to the unfavorable environmental factors and pathogen diseases (mildew, brown rust and pyrenophorosis) were identified – ‘Natalka’, ‘Pereiaslavka’, ‘Podolianka’, ‘Darynka Kyivska’, ‘Zbruch’, ‘Kyivska ostysta’, ‘Smuh­lianka’, ‘Snihurka’ and ‘Favorytka’ varieties. Studied varieties were involved to the breeding programs on creation of highly productive and highly adaptive winter wheat.

Purpose. To estimate a correlation between SSR-markers and morphological features by genetic distances on the basis of polymorphism of potato varieties. Methods. PCR analysis, cluster and correlation-regression analysis. Results. The results of analysis of potatoes varieties polymorphism based on molecular genetic and morphological marker features are presented. Varieties polymorphism was assessed on four microsatellite markers: STM0019, STM3009, STM3012, STM5136 and 42 morphological markers. According to the results of PCR analysis, it was determined that the frequency of identified alleles ranged from 0.021 to 0.33, the index of polymorphism on the average for studied markers was 0.76. Using cluster analysis, the genetic distances between varieties based on SSR and morphological markers were determined, and similar varieties and varieties that differ among themselves were identified. According to the obtained distribution, the correlation between the genetic distances by Mantel test are estimated, namely, a regression, in which the variables are similarity matrices, summing the pairwise similar values between the sampling points was defined. As a result of the estimation of genetic distances between the investigated genotypes of potatoes, it was revealed that the varieties ‘Skarbnytsia’ and ‘Yavir’ were the most similar by markers STM0019, STM3009, STM3012, STM5136. The distance between these varieties was 2.45, while the greatest distance – 3.74 was found among the varieties ‘Levada’ and ‘Dovira’, ‘Fantaziia’ and ‘Dovira’. According to marker morphological signs, the least value of genetic distances was 8.9 for varieties ‘Slovianka’ and ‘Poliske Dzherelo’, the most distant ones were ‘Okolytsia’ and ‘Dovira’, with values of 18.2. It was revealed that the potato variety ‘Dovira’ with the value of genetic distances of 18.2 and 3.74 for morphological and SSR markers respectively was the most distant from other investigated genotypes. The correlations were not found by Mantel test as a result of the analysis of genetic distances based on SSR-markers and morphological signs. Conclusions. The use of a complex of studies containing a description of morphological features and microsatellite markers is promising for identifying potato varieties, creating collections of well-known varieties and determining their differences.

Purpose. To analyze the phytosanitary state of soybean crops in the conditions of the Southern Steppe of Ukraine and to determine the most resistant cultivars to the complex of diseases for further use in breeding practice. Methods. 35 soybean sorts of different origin from the collection of the Plant Breeding and Genetics Institute – National Center of Seed and Cultivar Study (NAAS) were under research. Resistance of soybean varieties to peronosporosis, phomopsis and ash rot was evaluated in the context of natural infectious process and to a fusariosis – on a provocative basis. Results. The species composition of soybean pathogenic diseases was determined during the planting in the conditions of the Southern Steppe of Ukraine. During the vegetation period the development of sprout fusariosis and root rot, on adult plants in the flowering phase – perenospores, in the phase of beans ripening – ash rot, stems and beans burn and other diseases were observed. The most common in soybean agrocenosis were representatives of mycoflora: Fusarium sp., Pevonospora manskurica (Naum.) Syd., Macro­phomina phaseolina (Tassi.) Goid., Diaporthe phaseolorum (Cke. Et Ell) Sacc. var. sojae Wehm. It is worth to note that the specific composition of pathogens varied in dependence of soy cultivar. The varieties ‘Lambert’, ‘Yurivka’ and ‘Yuvileina’ were dominated with the infection of Fusarium spp., and also a large number of plants was infected by P. manskurica perenosporosis. ‘Chernovytska 8’ variety stood out with intense ash rot infestation. In the pathogenic complex ‘Apolon’, ‘Odesa 150’, ‘Yurivka’ and ‘L-2’ varieties the emergence of ash rot and phomapsis were marked. ‘Apolon’, ‘Ustia’ and ‘L-2’ varieties were diagnosed with phomopsis. Conclusions. According to the analysis, the soybean varieties ‘Arkadiia Odeska’, ‘Chornobura’, ‘Yatran’, ‘Berehynia’, ‘Stepovychka’, ‘Znakhidka’, ‘Medeia’, ‘Mariana’, ‘Vasylkivska’, ‘Faeton’, ‘Selek­ta’ were characterized by the complex resistance to fusario­sis, peronosporosis, ash rot and phomopsis.

Purpose. To establish the varietal features of the generative organs and plant morphological parts development; oil linseed yield formation during the cultivation with diffe­rent sowing density, which is regulated by the width between the rows (row spacing) and sowing rate. Methods. Field research was carried out along 2016–2018 in the multifactorial stationary experiment at the National University of Life and Environmental Sciences of Ukraine, separate subdivision “Agronomic Research Station” (Kyiv Oblast). Scheme of the experiment: factor V – variety: ‘Aisberh’, ‘Liryna’; factor W – width between the rows: 12.5, 25 and 37.5 cm; factor S – sowing rate: 4, 6, 8 and 10 million seeds/ha. Results. The oil linseed yield on average (over the years of research) varied from 1.03 to 1.64 t/ha, depending on the variety, row spacing and sowing rates. On average, (reference) yield of the ‘Liryna’ variety is 1.03–1.57 t/ha, and in terms of experimental years – 0.88–1.97 t/ha. ‘Liryna’ forms the highest yield with the sowing rate in 8 million seeds/ha with the width between the rows in 25 or 12.5 cm – 1.81 and 1.71 t/ha correspondently, and 1.65 t/ha with the width between the rows 37.5 cm. The optimum width of the row spacing for ‘Liryna’ variety and for all sowing rates is 25 cm. The ‘Aisberh’ linseed yield varied from 1.09 to 1.64 t/ha, and in terms of experimental years – from 0.90 to 1.78 t/ha. ‘Aisberh’ forms the highest yield with the sowing rate in 6 million seeds/ha and 25 cm of row spacing – 1.64 t/ha. The variants with increased sowing density with rates in 8 and 10 million seeds/ha lead to yield decreasing. Anyway, over the years of research, the number of boxes on the one flax plant changed depending on the sowing rate and row spacing. At the same time, more boxes were formed on the plants of ‘Liryna’ variety (1.44–3.88 pp.) in comparison with ‘Aisberh’ variety, although the last one was more variable on this indicator within the experimental variants. The weight of 1000 seeds of ‘Aisberh’ variety, depending on the variant of the experiment, varied from 7.31 to 7.58 g and of the variety ‘Liryna’ – from 6.44 to 6.65 g. ‘Aisberh’ variety in the weight of 1000 seeds exceeded ‘Liryna’ variety by 0,56–1,02 g in 2016, by 0,56–1,25 g in 2017 and by 1,01–1,09 g in 2018. Conclusions. Changing the sowing rate and row spacing causes variability of the yield components formation – the number of boxes per plant, the number of grains in the box and the weight of 1000 seeds, which determine the individual productivity of the plant. The highest yield of the ‘Liryna’ variety is formed by sowing 6 and 8 million similar seeds per hectare with the row spacing in 25 cm. The ‘Aisberh’ variety provides higher yield at the sowing rate in 6 million seed per hectare and 25 cm of row spacing, while the sow thicke­ning to 8 and 10 million seeds per hectare leads to yield decreasing.

Purpose. To determine the productivity of spring barley according to varietal characteristics and plant nutrition optimization in the conditions of the Southern Steppe of Ukraine. Methods. The research was carried out during the years 2013–2017 on the experimental field of the Mykolaiv National Agrarian University with the spring barley varieties ‘Adapt’, ‘Stalker’ and ‘Enei’. Results. Productivity elements of spring barley (the number of grains in the ear and their mass) were analyzed according to the variety and type of plant nutrition. During the years of research, lightly larger amount of grains have been formed by the nutrition factor in the ear of ‘Enei’ barley variety – 22.0 +_ pcs, which exceeded other varieties by 0.3–1.0 +_pcs, or 1.4–4.8%. Under conditions of root background (N30P30) fertilization the mass of one ear grains increased by 9.4% 8.0% and 7.9%, in comparison with non-fertilized reference groups of ‘Adapt’, ‘Stalker’ and ‘Enei’ barley varieties correspondently. And under conditions of non-root fertilization the mass increased too by 11.9–17.7%; 10.6–15.5% and 10.2–14.7% correspondently for these barley varieties. The maximum productivity of barley varieties was formed during the growing with background N30P30 fertilization and non-root plant nutrition in the period of vegetation with Orhanik D2 and Escort-Bio preparations. On average, over the years of research and by variety factor, the grain yield was 3.37–3.41 t/ha, which exceeded the yield of reference plant group grown on unfertilized field by 0.71–0.75 t/ha (26.7–28.2%), and by 0.4 t/ha (15.4%) in comparison with background root mineral fertilization only. The highest grain yield by feed factor was formed by ‘Enei’ variety – 3.36 t/ha, which exceeded the ‘Stalker’ and ‘Adapt’ varieties by 0.21 t/ha (6.3%) and 0.32 t/ha (9.5%) correspondently. Conclusions. On ave­rage, over the years of research, the highest productivity has been obtained with the ‘Enei’ variety. At the same time, the maximum yields of all barley varieties were obtained on the background of moderate dose of mineral fertilizers and non-root plant nutrition with Escort-bio preparation in the vegetation period.

Purpose. To study the varietal peculiarities of the buckwheat (Fagopyrum esculentum Moench) productivity formation in the conditions of unstable hydration of the Central Forest-Steppe zone of Ukraine, depending on the timing and methods of sowing. Methods. During 2015–2017, at the Ustymivka Experimental Station of Plant Production (Yuriev Plant Production Institute, NAAS of Ukraine) 6 varieties of buckwheat: ‘Yaroslavna’, ‘Slobozhanka’, ‘Ruslana’, ‘Ukrainka’, ‘Krupynka’, ‘SIN 3/02’ were studied. Buckwheat was sowed at a rate of 250 grains/m2 by wide (row spacing – 45 cm) and usual row (15 cm) methods into 3 steps with 5 days intervals: 5–6 May (soil temperature 14.5–16.6 °C), 10–11 and 15–16 May (16.4–19.1 and 16.9–17.3 °C correspondently). Results. The results of the three-year experiment indicate a significant impact of the factors (variety, timing and method of sowing) on the buckwheat productivity formation, which varied in a rather wide range: the number of grains on one plant varied from 2.8 to 17.4 pcs.; the weight of 1000 grains – up to 2.4 g; yield – from 0.1 to 1.2 t/ha; and in higher degree depended on the weather conditions in the spring period. The arid conditions at the beginning of the vegetation phase reduced the grain size and number on the plants that caused a decrease in yield, while more humid conditions increased these rates. At the same time, the varie­ties ‘SIN-3/02’ and ‘Krupynka’ in the dry conditions of 2017 showed increased yields in the case of sowing in the usual routine manner. In previous years they provided higher yields for wide-row sowing, while in unfavorable conditions for growth and development, the usual routine method was more suitable, and the term of sowing did not have a significant impact on this. The terms of sowing with the intervals in 5 days, can not mitigate the negative effects of weather conditions, in general. The method of sowing is an effective factor for high buckwheat productivity and yield formation that to a certain degree depends on biological characteristics of the variety. Conclusions. Among the studied buckwheat varieties, the ‘Yaroslavna’ variety characterized by the highest yield in case of wide-row sowing in the first decade of May (5–6.05). These elements of cultivation technology were better for the varieties ‘Slobozhanka’ and ‘Ruslana’. The second term of sowing (May 10–11) is more favorable for the varieties ‘SIN-3/02’ and ‘Ukrainka’ with the wide-row sowing. Buckwheat ‘Krupynka’ provided the highest yield with wide-row sowing in the first or second decade of May. In the case of sowing in the third term (15–16.05) all the varieties characterized by reduced productivity in comparison with other terms and methods of sowing

Purpose. To determine the optimal soil moisture conditions for intensive growth and high productivity of energy plantations of some willow cultivars in the conditions of Kyiv Polissya. Methods. The object of the study was the energy plantations of three willow cultivars: Salix viminalis L. cv. ‘Ternopilska’, S. triandra L. cv. ‘Yaroslava’ and S. dasyclados Wimm. cv. ‘Khors’. Plantations were created in 2009 in Boyarka forestry (Boyarka Forest Experimental Station). The soil is clayey-sandy. Plantations grew on three sites with different degrees of soil moisture: slightly-moisturized, well-moisturized and strongly-moisturized. Results. After two years of cultivation, the highest ‘plant survival rate’ was peculiar for well-moisturized soil. It was 98.5% for ‘Ternopilska’, 97.1% for ‘Yaroslava’, and 89.6% for ‘Khors’ varie­ties. The highest average height of two years old plants was observed on a well-moistened soil – 3.2±0.06 m (‘Yaroslava’ variety). ‘Ternopilska’ variety on less-wetted soil had the highest height. The plants of ‘Khors’ variety had near-the-same height, regardless of the level of soil moisture. Study of these plantations in the age of eight years, when the age of their above-the-ground part was of 5 years old, showed that ‘Yaroslava’ cultivar significantly exceeds the productivity of ‘Ternopilska’ and ‘Khors’, when grow on slightly- (122.0 t/ha) and well-moisturized soils (128.2 t/ha of raw biomass). The productivity of ‘Ternopilska’ and ‘Khors’ cultivars significantly decrease with the soil moisture increasing. ‘Ternopilska’ plantations produce 46.4 t/ha of raw cut mass after 5-year cultivation on slightly-moisturized soil, and only 19.8 t/ha on strongly-moisturized soil. ‘Khors’ variety characterized by the higher level of productivity on diffe­rent soil moistening (from 39.4 to 67.0 t/ha). Conclusions. Among the three studied cultivars of willow the highest growth and productivity indexes on clayey-sandy soils of the Kyiv Polissya has ‘Yaroslava’ cultivar. Optimal conditions for intensive growth of ‘Yaroslava’ cultivar peculiar to energy plantation on well-moisturized soils and for ‘Ternopilska’, and ‘Khors’ – on slightly-moisturized and well-moisturized soils. Over-moisturized, poorly drained soils are of little use for the efficient cultivation of energy willow raw materials.

Purpose. To provide the scientific basis for material costs, economic efficiency assess and bioenergy evaluation of “technological elements” of seed production of lettuce (Lactuca sativa L.) varieties in the conditions of Ukrainian Polissia. Methods. During the years 2013–2015 at the “Maiak” Research Station of the Institute of Vegetable and Melon Growing of the National Academy of Agra­rian Sciences of Ukraine, 12 salad varieties of different types were studied: leaf var. secalina (‘Snizhynka’, ‘Zorepad’, ‘Malakhit’, ‘Dublianskyi’), head var. capitata (‘Hodar’, ‘Smuhlianka’, ‘Dyvohrai’), romaine var. longifolia (‘Sovskyi’, ‘Scarb’) and stem var. angustana (‘Pohonych’, ‘Pastushok’, ‘Skrypal’). Results. The production of lettuce seeds is rather labour-intensive process. The largest share of expenditures in its overall structure (15–26%) takes crops care and harvesting, remunerations and costs for petrol and oil. The lettuce seed productivity (according to the varieties) was: 0,34–0,49 t/ha (leaf var.); 0.31–0.54 t/ha (head var.); 0.36–0.43 t/ha (romaine var.); 0,38–0,45 t/ha (stem var.). The highest value of the seed croppage provided the ‘Dyvohrai’ variety. The first cost for 1 kilogram of lettuce seed production varied from 36.67 to 63.87?. The highest cost was for ‘Hodar’ variety (63.87 ?/kg), ‘Snizhynka’ (58.24 ?/kg) and ‘Sovskyi’ (55.0 ?/kg), the lowest – for ‘Dyvohrai’ (36.67 ?/kg) and ‘Dublianskyi’ (40.41 ?/ha) varieties. The varieties, which formed a sufficiently high yield, ensured a high level of profitability: ‘Dublianskyi’ – 167%, ‘Dyvohrai’ – 142%, ‘Skarb’ – 108%, and ‘Skrypal’ – 123%. The coefficient of bioenergy efficiency of seed production of all lettuce varieties, for the non-seedling method of cultivation, was 1.2 on average, in particular for var. secalina – 1.1, var. capitata and var. longifolia – 1,2, var. angstana – 1.3. Conclusions. Calculated indicators of economic efficiency and bioenergy estimation of lettuce seed production confirm the expediency of all Lactuca sativa L. varieties cultivation for seed production purposes in the conditions of Ukrainian Polissia.

Purpose. To provide the scientific basis for material costs, economic efficiency assess and bioenergy evaluation of “technological elements” of seed production of lettuce (Lactuca sativa L.) varieties in the conditions of Ukrainian Polissia. Methods. During the years 2013–2015 at the “Maiak” Research Station of the Institute of Vegetable and Melon Growing of the National Academy of Agra­rian Sciences of Ukraine, 12 salad varieties of different types were studied: leaf var. secalina (‘Snizhynka’, ‘Zorepad’, ‘Malakhit’, ‘Dublianskyi’), head var. capitata (‘Hodar’, ‘Smuhlianka’, ‘Dyvohrai’), romaine var. longifolia (‘Sovskyi’, ‘Scarb’) and stem var. angustana (‘Pohonych’, ‘Pastushok’, ‘Skrypal’). Results. The production of lettuce seeds is rather labour-intensive process. The largest share of expenditures in its overall structure (15–26%) takes crops care and harvesting, remunerations and costs for petrol and oil. The lettuce seed productivity (according to the varieties) was: 0,34–0,49 t/ha (leaf var.); 0.31–0.54 t/ha (head var.); 0.36–0.43 t/ha (romaine var.); 0,38–0,45 t/ha (stem var.). The highest value of the seed croppage provided the ‘Dyvohrai’ variety. The first cost for 1 kilogram of lettuce seed production varied from 36.67 to 63.87?. The highest cost was for ‘Hodar’ variety (63.87 ?/kg), ‘Snizhynka’ (58.24 ?/kg) and ‘Sovskyi’ (55.0 ?/kg), the lowest – for ‘Dyvohrai’ (36.67 ?/kg) and ‘Dublianskyi’ (40.41 ?/ha) varieties. The varieties, which formed a sufficiently high yield, ensured a high level of profitability: ‘Dublianskyi’ – 167%, ‘Dyvohrai’ – 142%, ‘Skarb’ – 108%, and ‘Skrypal’ – 123%. The coefficient of bioenergy efficiency of seed production of all lettuce varieties, for the non-seedling method of cultivation, was 1.2 on average, in particular for var. secalina – 1.1, var. capitata and var. longifolia – 1,2, var. angstana – 1.3. Conclusions. Calculated indicators of economic efficiency and bioenergy estimation of lettuce seed production confirm the expediency of all Lactuca sativa L. varieties cultivation for seed production purposes in the conditions of Ukrainian Polissia.