Purpose. To establish correlation dependence of influence of such factors as seeding rate, sowing time and seeding methods on yield indicators, as well as individual response of winter wheat varieties to them in case of the ecological system of seed production, that would allow to form elements of intensive varietal technology and obtain the genetically determined productivity potential of the variety in the future. Methods. Weight measuring was used to determine seed yield; the reliability of the experiment results was identified by statistical evaluation, analysis of variance and regression procedure. Results. During the period of investigation, the weather conditions differed significantly both for the temperature regime and the amount of precipitation, but the stability of grain and seed yield over years was the main requirement to varieties, that allowed to study the intergenotypic correlation relationships of crop yield indices and the dynamics of their changes under the effect of ecological factors. In the course of investigation, winter wheat yield indices were fixed annually from 684 plots, which were grouped and analyzed for factors of influence in order to ensure the complete certainty. Conclusions. Variants of investigation were defined for the certified seed yield and environmental factors (sowing time and seeding method, seeding rate), that had strong positive correlation relationships. Seeding rate and seeding method had the greatest impact on 1000 kernel weight. For tille­ring coefficient, varieties depending on the variant of the investigation had a negative close correlation relationship, which was greatly affected by seeding rate. For correlation relationships, winter wheat varieties ‘Bohdana’ and ‘Slavna’ appeared to be the most stable, ‘Chorniava’ and ‘Astarta’ were the most plastic.

Purpose. To establish correlation dependence of influence of such factors as seeding rate, sowing time and seeding methods on yield indicators, as well as individual response of winter wheat varieties to them in case of the ecological system of seed production, that would allow to form elements of intensive varietal technology and obtain the genetically determined productivity potential of the variety in the future. Methods. Weight measuring was used to determine seed yield; the reliability of the experiment results was identified by statistical evaluation, analysis of variance and regression procedure. Results. During the period of investigation, the weather conditions differed significantly both for the temperature regime and the amount of precipitation, but the stability of grain and seed yield over years was the main requirement to varieties, that allowed to study the intergenotypic correlation relationships of crop yield indices and the dynamics of their changes under the effect of ecological factors. In the course of investigation, winter wheat yield indices were fixed annually from 684 plots, which were grouped and analyzed for factors of influence in order to ensure the complete certainty. Conclusions. Variants of investigation were defined for the certified seed yield and environmental factors (sowing time and seeding method, seeding rate), that had strong positive correlation relationships. Seeding rate and seeding method had the greatest impact on 1000 kernel weight. For tille­ring coefficient, varieties depending on the variant of the investigation had a negative close correlation relationship, which was greatly affected by seeding rate. For correlation relationships, winter wheat varieties ‘Bohdana’ and ‘Slavna’ appeared to be the most stable, ‘Chorniava’ and ‘Astarta’ were the most plastic.

Мета. Дослідити вплив грибних хвороб на продуктивність різних за стійкістю сортів пшениці озимої з використанням штучних інфекційних фонів. Методи. Польовий – оцінка стійкості сортозразків до грибних хвороб на інфекційних фонах. Лабораторний – структурний аналіз сортозразків. Математико-статистичний – оцінка результатів досліджень і аналіз кореляційних зв’язків між отриманими даними. Результати. Грибні хвороби, як найпоширеніші та шкідливі, уражують різні органи рослин та спричиняють недобір урожаю, погіршують товарну та насіннєву якість зерна. Наведено результати польових експериментальних досліджень за 2012–2017 рр. із вивчення впливу грибних хвороб на показники врожайності пшениці озимої. Встановлено, що ураження пшениці озимої септоріозом (Septoria tritici Rob.) та борошнис­тою росою (Erysiphe graminis DS. f. sp. tritici) негативно впливало на довжину колоса, кількість зерен у ньому, масу зерна з колоса та масу 1000 зерен. Однак, у досліджуваних сортозразків показники продуктивності змінювалися по-різному. Най­толерантнiшими проти грибних хвороб були високопродуктивні сорти пшениці озимої ‘Смуглянка’ та ‘Новокиївська’. У стійкого проти септоріозу сорту ‘Смуглянка’, за 75%-го ступеня ураження, зниження показників продуктивності становило від 1,4 до 12,2%, тоді як у сприйнятливого сортозразка ‘УК 1731’ – від 6,2 до 16,7%. Аналогічний стан спостерігався і на стійкому проти борошнистої роси сорті ‘Новокиївська’. Висновки. Відібрані два толерантні високопродуктивні сорти пшениці озимої ‘Смуглянка’ та ‘Новокиївська’ (стійкість 7–6 балів) можуть протистояти ураженню септоріозом і борошнистою росою без втрати продуктивності, а також бути перспективним джерелом стійкості проти цих хвороб та становити інтерес для подальшої селекційної роботи в Україні.

Purpose. To investigate the effect of fungal diseases on the productivity of winter wheat varieties of various resis­tance using artificial infection backgrounds. Methods. Field one – assessment of the resistance of variety samples to fungal diseases on infection backgrounds. Laboratory one – structural analysis of variety samples. Mathematical-statistical one – evaluation of investigation results and analysis of correlations between the obtained data.Results. Fungal diseases as the most widespread and harmful affect various organs of plants and cause poor harvest, deteriorate commercial and seed quality of grain. The results of field experiments in 2012–2017 on the effects of fungal diseases on the yields of winter wheat in the collection are given. It is defined that the infection of winter wheat with fungus (Septoria tritici Rob.) and powdery mildew (Erysiphe graminis DS. F. sp. tritici) adversely affected the length of the ear, the number of grains in it, grain mass per ear and the thousand-kernel weight. However, productivity indices changed differently in investigated variety samples. The high-yielding wheat varieties ‘Smuhlianka’ and ‘Novokyivska’ were the most tolerant to the fungal diseases. In the Septoria-resistant variety ‘Smuhlianka’ at 75% of infestation the decrease in productivity was from 1,4 to 12,2%, whereas the in susceptible variety sample ‘UK 1731’ it was from 6,2 to 16,7%. A similar situation was observed in the variety ‘Novokyivska’ resistant to powdery mildew. Conclusions. Selected tolerant and highly productive varieties ‘Smuhlianka’ and ‘Novo­kyivska’ (grade 7–6) can resist to Septoria disease and powdery mildew without productivity loss, they are considered as a promising source of resistance to these diseases and be of interest for further breeding in Ukraine. | Цель. Исследовать влияние грибных болезней на продуктивность различающихся по устойчивости сортов пшеницы озимой с использованием искусственных инфекционных фонов. Методы. Полевой – оценка устойчивости сортообразцов к грибным болезням на инфекционных фонах. Лабораторный – структурный анализ сортообразцов. Математико-статистический – оценка результатов исследований и анализ корреляционных связей между полученными данными. Результаты. Грибные болезни, как самые распространенные и вредоносные, поражают разные органы растений и вызывают недоборы урожая, ухудшают товарное и семенное качество зерна. Приведены результаты полевых экспериментальных исследований в 2012–2017 гг. по изучению влияния грибных болезней на показатели урожайности озимой пшеницы. Установлено, что пораженность пшеницы озимой грибом (Septoria tritici Rob.) и мучнистой росой (Erysiphe graminis DS. F. sp. tritici) отрицательно влияла на длину колоса, количество зерен в колосе, массу зерна с колоса и массу 1000 зерен. Однако, у исследованных сортов по-разному изменялись показатели продуктивности. Наиболее толерантными к грибным болезням были высокопродуктивные сорта пшеницы озимой ‘Смуг­лянка’ и ‘Новокиевская’. В устойчивого к септориозу сорта ‘Смуглянка’, при степени поражения 75%, снижение показателей продуктивности составило от 1,4 до 12,2%, тогда как у восприимчивого сортообразца ‘УК 1731’ – от 6,2 до 16,7%. Аналогичные показатели наблюдались и в устойчивого к мучнистой росе сорта ‘Новокиевская’. Выводы. Отоб­раны два толерантных высокопродуктивных сорта пшеницы озимой ‘Смуглянка’ и ‘Новокиевская’ (устойчивость 7–6 баллов) могут противостоять поражению септориозом и мучнистой росой без потери продуктивности, а также быть перспективным источником устойчивости к этим болезням и представлять интерес для дальнейшей селекционной работы в Украине. | Мета. Дослідити вплив грибних хвороб на продуктивність різних за стійкістю сортів пшениці озимої з використанням штучних інфекційних фонів. Методи. Польовий – оцінка стійкості сортозразків до грибних хвороб на інфекційних фонах. Лабораторний – структурний аналіз сортозразків. Математико-статистичний – оцінка результатів досліджень і аналіз кореляційних зв’язків між отриманими даними.Результати. Грибні хвороби, як найпоширеніші та шкідливі, уражують різні органи рослин та спричиняють недобір урожаю, погіршують товарну та насіннєву якість зерна. Наведено результати польових експериментальних досліджень за 2012–2017 рр. із вивчення впливу грибних хвороб на показники врожайності пшениці озимої. Встановлено, що ураження пшениці озимої септоріозом (Septoria tritici Rob.) та борошнис­тою росою (Erysiphe graminis DS. f. sp. tritici) негативно впливало на довжину колоса, кількість зерен у ньому, масу зерна з колоса та масу 1000 зерен. Однак, у досліджуваних сортозразків показники продуктивності змінювалися по-різному. Най­толерантнiшими проти грибних хвороб були високопродуктивні сорти пшениці озимої ‘Смуглянка’ та ‘Новокиївська’. У стійкого проти септоріозу сорту ‘Смуглянка’, за 75%-го ступеня ураження, зниження показників продуктивності становило від 1,4 до 12,2%, тоді як у сприйнятливого сортозразка ‘УК 1731’ – від 6,2 до 16,7%. Аналогічний стан спостерігався і на стійкому проти борошнистої роси сорті ‘Новокиївська’. Висновки. Відібрані два толерантні високопродуктивні сорти пшениці озимої ‘Смуглянка’ та ‘Новокиївська’ (стійкість 7–6 балів) можуть протистояти ураженню септоріозом і борошнистою росою без втрати продуктивності, а також бути перспективним джерелом стійкості проти цих хвороб та становити інтерес для подальшої селекційної роботи в Україні.

Purpose. To determine and substantiate practical aspects of statistical analysis application for management results of the morphological description of cutting lettuce (Lactuca sativa L.) varieties when identifying them during corresponding phenological phases of growth and development. Methods. Field study, analytical approach based on descriptive statistics and cluster analysis. Results. Quantitative values of display of such morphological characters as leaf rosette diameter, lettuce head size, leaf blade thickness and its venation were determined for the Lactuca sativa L. varieties. Statistical indices of four morphological characters of randomized sampling frame of seven cutting lettuce varie­ties were determined and the results of statistical analysis were interpreted. Cutting lettuce of loose leaf and capitate varieties was identified during corresponding phenological phases of growth and development. The most suitable method for clustering cutting lettuce varieties was defined. The results of clustering were interpreted. It was found that ‘Hodar’ variety differed greatly from others, ‘Dumka’ and ‘Olzhych’ varieties were the most similar. Conclusions. The results of the identification allowed to establish that capitate lettuce varieties were similar in the following combinations: ‘Bona’ and ‘Dyvohray’, ‘Olzhych’ and ‘Dumka’. According to the duration of interphase periods, it can be noted that such varieties as ‘Dumka’ and ‘Dyvohrai’ had the highest rate of maturation in comparison with ‘Bona’ and ‘Hodar’ varieties, and the lowest one as compared to the ‘Olzhych’ variety

Purpose. To determine and substantiate practical aspects of statistical analysis application for management results of the morphological description of cutting lettuce (Lactuca sativa L.) varieties when identifying them during corresponding phenological phases of growth and development. Methods. Field study, analytical approach based on descriptive statistics and cluster analysis. Results. Quantitative values of display of such morphological characters as leaf rosette diameter, lettuce head size, leaf blade thickness and its venation were determined for the Lactuca sativa L. varieties. Statistical indices of four morphological characters of randomized sampling frame of seven cutting lettuce varie­ties were determined and the results of statistical analysis were interpreted. Cutting lettuce of loose leaf and capitate varieties was identified during corresponding phenological phases of growth and development. The most suitable method for clustering cutting lettuce varieties was defined. The results of clustering were interpreted. It was found that ‘Hodar’ variety differed greatly from others, ‘Dumka’ and ‘Olzhych’ varieties were the most similar. Conclusions. The results of the identification allowed to establish that capitate lettuce varieties were similar in the following combinations: ‘Bona’ and ‘Dyvohray’, ‘Olzhych’ and ‘Dumka’. According to the duration of interphase periods, it can be noted that such varieties as ‘Dumka’ and ‘Dyvohrai’ had the highest rate of maturation in comparison with ‘Bona’ and ‘Hodar’ varieties, and the lowest one as compared to the ‘Olzhych’ variety

Purpose. To determine the effect of the basic organo-mineral fertilizer on the formation and stability of grain quality of winter wheat varieties in multiple crop rotation after black fallow as a predecessor. Methods. Field experiments were based on a multifactorial scheme using split-plot method with due regard to all requirements of the field experiment procedure, analysis of variance was used for statistical processing of the obtained results. Results. Investigation data was given concerning determination of grain quality indices in winter wheat varieties of diffe­rent ecotypes after black fallow as a predecessor depending on organo-mineral fertilizer application in the Left-Bank Forest-Steppe zone of Ukraine. In average for the period of investigation (2011–2015), the highest protein content in winter wheat grains was formed in no treatment variant [in such varieties as ‘Doridna’ (14.1%), ‘Dykanka’ (14.3%) and ‘Levada’ (14.2%)] and in case of organo-mineral fertilizer application [in the varieties ‘Hordovyta’ (14.0%), ‘Kalyta’ (14.0%), ‘Dykanka’ (14.7%) and ‘Levada’ (14.6%)]. The highest content of crude gluten in grains, without regard for the variant of the experiment, was found in the following varieties as ‘Dykanka’ (24.9–25.1%) and ‘Levada’ (23.7–25.4%). Conclusions. It was established that the content of protein and crude gluten in grains as well as the falling number of winter wheat was highly dependent on such factors as the variety and the year of cultivation as compared to the fertilizer background. The following varieties as ‘Hordovyta’, ‘Mulan’, Dykanka’ and ‘Levada’ were very sensitive to the application of organo-mineral fertilizer for the protein content, while ‘Hordovyta’ (2.4%), ‘Levada’ (1.7%), ‘Borvii’ (1.2%) and ‘Mulan’ (1.1%) – for the crude gluten content.

Purpose. To determine the effect of the basic organo-mineral fertilizer on the formation and stability of grain quality of winter wheat varieties in multiple crop rotation after black fallow as a predecessor. Methods. Field experiments were based on a multifactorial scheme using split-plot method with due regard to all requirements of the field experiment procedure, analysis of variance was used for statistical processing of the obtained results. Results. Investigation data was given concerning determination of grain quality indices in winter wheat varieties of diffe­rent ecotypes after black fallow as a predecessor depending on organo-mineral fertilizer application in the Left-Bank Forest-Steppe zone of Ukraine. In average for the period of investigation (2011–2015), the highest protein content in winter wheat grains was formed in no treatment variant [in such varieties as ‘Doridna’ (14.1%), ‘Dykanka’ (14.3%) and ‘Levada’ (14.2%)] and in case of organo-mineral fertilizer application [in the varieties ‘Hordovyta’ (14.0%), ‘Kalyta’ (14.0%), ‘Dykanka’ (14.7%) and ‘Levada’ (14.6%)]. The highest content of crude gluten in grains, without regard for the variant of the experiment, was found in the following varieties as ‘Dykanka’ (24.9–25.1%) and ‘Levada’ (23.7–25.4%). Conclusions. It was established that the content of protein and crude gluten in grains as well as the falling number of winter wheat was highly dependent on such factors as the variety and the year of cultivation as compared to the fertilizer background. The following varieties as ‘Hordovyta’, ‘Mulan’, Dykanka’ and ‘Levada’ were very sensitive to the application of organo-mineral fertilizer for the protein content, while ‘Hordovyta’ (2.4%), ‘Levada’ (1.7%), ‘Borvii’ (1.2%) and ‘Mulan’ (1.1%) – for the crude gluten content.

Purpose. Analysis of the process of hexaploid triticale breeding for winter hardiness by intraspecific hybridization method using systemic ecological tests under contrasting conditions. Methods. Dialectical investigation, field experiments, laboratory testing and statistical evaluation. Results. The results of breeding winter and alternate triticale varieties possessing a complex of valuable traits by the method of intraspecific hybridization of forms of different types of development using systemic ecological tests under contrasting conditions (Forest-Steppe – extremely arid Steppe) and at low temperatures were presented. During the years of research (1980–2005), 18 varieties were developed and transferred to the state testing, 17 of them were registered. Conclusions. Thus, the effective selection of highly productive genotypes with increased and high winter hardiness is possible from populations obtained by crossing hexaploid triticale of different types of development (winter triticale with spring and alternate ones) and contrasting level of frost and winter hardiness. During the period of 1980–2015, medium-tall and dwarf varieties of winter (‘Amfidyploid 256’, ‘Garne’, ‘Kharroza’, ‘Rarytet’, ‘Timofey’, etc.) and alternate (‘Nikanor’, ‘Yaroslava’, ‘Plastun Volynskyi’) triticales were developed. They are superior to the standard varieties of soft winter wheat for the critical temperature of freezing by -0.5...- 2.0 °C, characterized by increased (up to 9–12 t/ha) grain yield of various quality depending on the purpose of use.

Purpose. Analysis of the process of hexaploid triticale breeding for winter hardiness by intraspecific hybridization method using systemic ecological tests under contrasting conditions. Methods. Dialectical investigation, field experiments, laboratory testing and statistical evaluation. Results. The results of breeding winter and alternate triticale varieties possessing a complex of valuable traits by the method of intraspecific hybridization of forms of different types of development using systemic ecological tests under contrasting conditions (Forest-Steppe – extremely arid Steppe) and at low temperatures were presented. During the years of research (1980–2005), 18 varieties were developed and transferred to the state testing, 17 of them were registered. Conclusions. Thus, the effective selection of highly productive genotypes with increased and high winter hardiness is possible from populations obtained by crossing hexaploid triticale of different types of development (winter triticale with spring and alternate ones) and contrasting level of frost and winter hardiness. During the period of 1980–2015, medium-tall and dwarf varieties of winter (‘Amfidyploid 256’, ‘Garne’, ‘Kharroza’, ‘Rarytet’, ‘Timofey’, etc.) and alternate (‘Nikanor’, ‘Yaroslava’, ‘Plastun Volynskyi’) triticales were developed. They are superior to the standard varieties of soft winter wheat for the critical temperature of freezing by -0.5...- 2.0 °C, characterized by increased (up to 9–12 t/ha) grain yield of various quality depending on the purpose of use.

Purpose. To evaluate hazelnut cultivars, species and hybrids from the genetic collection of Corylus spp. in the National Dendrological Park “Sofiyivka” of the NAS of Ukraine for the complex of economic characters. An attempt has been made to analyze the information on Corylus spp. identity, taxonomy and description, dissemination and ecological requirements of the species, possibilities to use the genetic potential for developing new cultivars. Methods. The value of the Corylus spp. collection representatives was investigated using conventional testing procedures. For summarizing information concerning phylogenetic reconstruction of the Corylus L. genus and hazelnut, a number of scientific publications to be proposed for discussion was analyzed. The oil content in hazelnut kernels and the fatty acid composition was determined using official methods. Results. The best samples of hazelnut genetic collection were included into the broad hybridization programme, and C. chinensis Franch. representatives as well. A number of hybrid seedlings was obtained including new hazelnut cultivars ‘Sofiyivsky 1’, ‘Sofiyivsky 2’ and ‘Sofiyivsky 15’ which were characterized by spherical or almost spherical fruits, high winter hardiness and drought resistance, as well as the absence of rhythmicity in fruiting. Conclusions. The collection of varieties, forms, cultivars and species of the Corylus L. genus created during the last years can be the base for hazelnut breeding in Ukraine.

Cytospora species are destructive canker and dieback pathogens of woody hosts in natural and agroecosystems around the world. In this genus, molecular identification has been limited due to the paucity of multi-locus sequence typing studies and the lack of sequence data from type specimens in public repositories, stalling robust phylogenetic reconstructions. In most cases a morphological species concept could not be applied due to the plasticity of characters and significant overlap of morphological features such as spore dimensions and fruiting body characters. In this study, we employed a molecular phylogenetic framework with the inclusion of four nuclear loci (ITS, translation elongation factor 1-alpha, actin, and beta-tubulin) to unveil the biodiversity and taxonomy of this understudied important genus of plant pathogens. Phylogenetic inferences based on 150 Californian isolates revealed 15 Cytospora species associated with branch and twig cankers and dieback of almond, apricot, cherry, cottonwood, olive, peach, pistachio, plum, pomegranate, and walnut trees in California. Of the 15 species recovered in this study, 10 are newly described and typified, in addition to one new combination. The pathogenic status of the newly described Cytospora species requires further investigation as most species were associated with severe dieback and decline of diverse and economically important fruit and nut crops in California.

Purpose. To create and study genotypes of the secondary triticale of the hexaploid level for their effective use in further breeding and plant growing. Methods. Field study, laboratory analyses, intraspecific hybridization with subsequent individual selection. Results. New genotypes of the secon­dary triticale of the hexaploid level have been created and characterized for economic characters and agroecological traits and properties. Series of short-stem winter triticale was represented by ‘Pshenychne’, ‘Chaian’ to be adapted to the conditions of both intensive and organic farming. They are characterized by high drought resistance and winter hardiness, resistance to lodging, grain shedding, grain germination in the spike and spike fragility as well as by immunity to fungal diseases providing a high level of yield and technological quality of grain. The following new constant forms of triticale as ‘ПС_1-12’, ‘ПС_2-12’, ‘ПС_3-12’, that have an average height of the stem and belong to the Polissia-Forest-Steppe and Forest-Steppe ecotypes, demonstrated high productivity and adaptability in organic farming, particularly in case of the use of biologized elements of agrotechnology. Conclusions. For the creation a new parent material during breeding of hexaploid triticale, the method of intraspecific hybridization is desirable with the use of parent material to be contrasting for eco-geographical origin and adapted local forms, followed by individual selection of genotypes with the desired characteristics and properties in cleavable hybrid populations. New genotypes of the secondary triticale have been created and characterized for breeding, genetic and agroecological traits and properties. In breeding practice, it is advisable to use a whole new approach of agroecological and genetic certification of genotypes for the effective solution of a number of theoretical and practical tasks facing modern ecological and adaptive breeding. New parent material of the secondary winter triticale and scientific support for its cultivation is proposed for further breeding and plant growing.

Purpose. To create and study genotypes of the secondary triticale of the hexaploid level for their effective use in further breeding and plant growing. Methods. Field study, laboratory analyses, intraspecific hybridization with subsequent individual selection. Results. New genotypes of the secon­dary triticale of the hexaploid level have been created and characterized for economic characters and agroecological traits and properties. Series of short-stem winter triticale was represented by ‘Pshenychne’, ‘Chaian’ to be adapted to the conditions of both intensive and organic farming. They are characterized by high drought resistance and winter hardiness, resistance to lodging, grain shedding, grain germination in the spike and spike fragility as well as by immunity to fungal diseases providing a high level of yield and technological quality of grain. The following new constant forms of triticale as ‘ПС_1-12’, ‘ПС_2-12’, ‘ПС_3-12’, that have an average height of the stem and belong to the Polissia-Forest-Steppe and Forest-Steppe ecotypes, demonstrated high productivity and adaptability in organic farming, particularly in case of the use of biologized elements of agrotechnology. Conclusions. For the creation a new parent material during breeding of hexaploid triticale, the method of intraspecific hybridization is desirable with the use of parent material to be contrasting for eco-geographical origin and adapted local forms, followed by individual selection of genotypes with the desired characteristics and properties in cleavable hybrid populations. New genotypes of the secondary triticale have been created and characterized for breeding, genetic and agroecological traits and properties. In breeding practice, it is advisable to use a whole new approach of agroecological and genetic certification of genotypes for the effective solution of a number of theoretical and practical tasks facing modern ecological and adaptive breeding. New parent material of the secondary winter triticale and scientific support for its cultivation is proposed for further breeding and plant growing.

Purpose. To investigate features of commercial head quality formation in varieties of cutting lettuce (Lactuca sativa var. capitata L.) for different growing methods. To study the influence of growing methods for cutting lettuce plants on the weight of commercial heads, indices of yield and quality of freshly harvested products. Methods. Field study, laboratory testing and statistical evaluation. Results. The results of studying peculiarities of head formation in such cutting lettuce varieties as ‘Godar’ (control), ‘Smuhlianka’, ‘Olzhych’ and ‘Dyvohrai’ were shown. Based on the results of phenological observations, the duration of interstage periods of growth and development of cutting lettuce plants was determined for the different growing methods. The model of cutting lettuce of capitata variety for different growing methods was presented in terms of biochemical parameters (content of dry matter, vitamin C, nitrates, amount of sugars). The influence of growing methods for cutting lettuce plants on the commercial head weight, indices of yield and quality of freshly harvested products was studied. Obtained results confirmed that in early ripening varie­ti­es the heads were smaller (150 g) and not dense, in late ripening varieties they were large and dense, weight was 150–500 g. Freshly harvested commercial products of head lettuce in case of seedling cultivation was characterized by a slight increase in dry matter content by 0.15–0.29%. The corresponding pattern was observed for the total sugar content. Its amount was slightly higher: 1.3–1.9% in case of direct sowing and 1.6–1.9% – for seedlings cultivation. The content of ascorbic acid (vitamin C, mg/100 g) was the highest in the ‘Dyvohrai’ variety despite of the method of growing. The largest quantity of nitrates in lettuce heads was in the inner stem (480 mg/kg), while in the middle of the head it was reduced to 110 mg/kg. Conclusions. Freshly harvested heads of cutting lettuce were analyzed for the content of such basic biochemical indices as dry matter, vitamin C, protein, nitrates, amount of sugars. Biochemical characteristics of freshly harvested products of heading lettuce in case of direct sowing and non-seedling methods of growing were within the error being almost identical with minor deviations. According to the study results, a typical model of capitate lettuce variety was designed which will have practical application in qualification examination of plant varieties.

Purpose. To investigate features of commercial head quality formation in varieties of cutting lettuce (Lactuca sativa var. capitata L.) for different growing methods. To study the influence of growing methods for cutting lettuce plants on the weight of commercial heads, indices of yield and quality of freshly harvested products. Methods. Field study, laboratory testing and statistical evaluation. Results. The results of studying peculiarities of head formation in such cutting lettuce varieties as ‘Godar’ (control), ‘Smuhlianka’, ‘Olzhych’ and ‘Dyvohrai’ were shown. Based on the results of phenological observations, the duration of interstage periods of growth and development of cutting lettuce plants was determined for the different growing methods. The model of cutting lettuce of capitata variety for different growing methods was presented in terms of biochemical parameters (content of dry matter, vitamin C, nitrates, amount of sugars). The influence of growing methods for cutting lettuce plants on the commercial head weight, indices of yield and quality of freshly harvested products was studied. Obtained results confirmed that in early ripening varie­ti­es the heads were smaller (150 g) and not dense, in late ripening varieties they were large and dense, weight was 150–500 g. Freshly harvested commercial products of head lettuce in case of seedling cultivation was characterized by a slight increase in dry matter content by 0.15–0.29%. The corresponding pattern was observed for the total sugar content. Its amount was slightly higher: 1.3–1.9% in case of direct sowing and 1.6–1.9% – for seedlings cultivation. The content of ascorbic acid (vitamin C, mg/100 g) was the highest in the ‘Dyvohrai’ variety despite of the method of growing. The largest quantity of nitrates in lettuce heads was in the inner stem (480 mg/kg), while in the middle of the head it was reduced to 110 mg/kg. Conclusions. Freshly harvested heads of cutting lettuce were analyzed for the content of such basic biochemical indices as dry matter, vitamin C, protein, nitrates, amount of sugars. Biochemical characteristics of freshly harvested products of heading lettuce in case of direct sowing and non-seedling methods of growing were within the error being almost identical with minor deviations. According to the study results, a typical model of capitate lettuce variety was designed which will have practical application in qualification examination of plant varieties.