Надійшла 14.06.2022 Мета. Визначити вплив густоти рослин та обробітку препаратом Ретенго® на масу 1000 зерен та врожайність насіння ліній -батьківських компонентів гібридів кукурудзи за умов зрошення. Методи. Дослідження проведено з використанням польових (визначення врожайності ліній -батьківських компонентів), лабораторних (маси 1000 зерен), аналітичних і математично-статистичних методів. Результати. Максимальна врожайність середньоранньої лінії ДК247 у середньому за фактором густотирослин 90 тис. росл./га становила 4,70 т/га, середньостиглої лінії ДК 205710 за густоти 80 тис. росл./га -5,42 т/га, середньопізньої лінії ДК 445 за густоти 70 тис. росл./га -7,08 т/га насіння. Найбільш продуктивна середньопізня лінія ДК445 -батьківський компонент гібридів Віра, Гілея, Арабат негативно реагує на загущеність посівів. Урожайність насіння за густоти 100 тис. росл./га знизилася на 1,03 т/га, або на 15% порівняно з урожайністю за оптимальної густоти 70 тис. росл./га. За обробки рослин препаратом Ретенго® збільшився показник маси 1000 зерен на 10 -12 г, або на 3,7 -5,4% порівняно з контролем без обробки. Обробка рослин рістрегулювальним фунгіцидним препаратом Ретенго® сприяла підвищенню Агроекологія, радіологія, меліорація

Goal. To determine the effect of method of irrigation and plant density on growth, development, and yield of seed lines of corn, which are the parental components of the innovative hybrids. Methods. Field, laboratory, comparison, generalization. The study had been carried out during 2016 -2018. Results. It is established that the main factor influencing the duration of the period «germination -flowering» of lines of corn was the ripening group. The duration of the period increased from 49 (in early-maturing lines) to 62 days (in late-maturing lines). The plant density was quite an effective factor influencing the timing of the flowering of female inflorescences. The greatest reaction to the thickening was observed in the mid, medium late and late maturing lines from FAO 380 -500. This reaction of the lines to stand can be used in hybridization areas for the synchronization of the flowering of parental components of hybrids. It is established that drip irrigation promotes the formation of a higher grain yield of corn. Compared with sprinkler irrigation, the yield increase due to drip irrigation was 0.56 t/ha or 12.1%. The highest increase in seed yield was fixed for lines FAO 300 -500 (from 0.88 to 1.18 t/ha). The parent line DK445 (FAO 420), on average for the period of the research, proved to be the most productive one -the average seed yield made 5.79 t/ha. Conclusions. The specific reaction is fixed of lines on the density of cenosis. For each parent form, there is an optimum plant density that should be considered in areas of hybridization to obtain the maximum yield of seeds. The obtained results show that for the planning seed production lines of corn, which are the parental components of hybrids, it is necessary to take into account their genotypic features, the reaction on the density of the growing and irrigation method.

The purpose. To determine optimum root formation in crop in vitrо of mediumearly cultivars of potato Nevskaya depending on acidity of nutrient medium(pH), intensity of illumination and photoperiod for increaseof production of the initial improved planting stock. Methods. Complex use of laboratory, mathematical and statistical, calculation-comparative methods and system analysis. Results. Experimental data concerning influence of acidity of nutrient medium (pH), intensity of illumination and photoperiod on induction of root formation are brought at microclonal reproduction of the improved initial material. It is fixed that рН of nutrient medium influences intensity of root formation. Conclusions. The maximum productivity indexes and economic efficiency of plants in vitro of medium-early cultivar Nevskaya are gained at рН=5,3, photoperiod of 16 h and illumination of 2500 l. Intensity of root formation made 92,7%, mass of average microtuber -667,7 mg, mass of microtubers for 1 plant -617,3 mg, amount of microtubers in mass more than 350 mg -79,1% at profitableness of production of 117 %, cost prices 7,37 hrn/microtuber, conditional net profit -8,63 hrn/microtuber. Key words: root formation, amount of interstitial sites, height of plants, acidity of nutrient medium, photoperiod, intensity of illumination, mass of microtubers.The necessary basis for the development of the technology for obtaining microand minibools is the knowledge of the mechanism of tuber formation as a physiological and biochemical process and its methods of regulation. It is established that tuber formation in a plant is induced by a system of factors, :excess of assimilants, hormonal state of the plant, photoperiod, temperature decrease, nitrogen deficiency, change of tragacanth centers due to the damping of the activity of the apical meristem of the stalk in the direction of soboles and tubers, ontogenetic state of the plant [1 , 2]

The purpose. To determine optimum regime for formation of tubers of grades of potato in vitro of different groups of ripeness depending on storey of cuttings of test glass plants and content of nutrient medium. Methods. Complex use of laboratory, mathematical-and-statistical, calculation-andcomparative methods and systems analysis. Results. Experimental data about influence of storey of cuttings of test glass plants and content of nutrient medium on induction of formation of tubers are resulted at reproduction of different by group of ripeness grades of potato in crop in vitro. Conclusions. The best productivity indexes are gained at growing microtubers of middle-ripening grade of potato Yavir on nutrient medium of Institute of irrigation farming agriculture of NAAS at plants from 1-3-rd storey of a cutting. So, the mass of average microtuber has made 502 mg, mass of microtubers for 1 plant -509,8 mg. Yield of microtubers in mass more than 350 mg -84,7%, intensity of formation of tubers made 101,5%.Key words: potato, grade, crop in vitro, storey of a cutting, microtuber, productivity.https://doi.org/10.31073/agrovisnyk201805-07Introduction. The main problem of potato growing in the south of Ukraine is the increased threat of the defeat of plants by viral, fungal and bacterial diseases, greatly complicates the management of seed production, reduces the quantity and quality of the crop [1-4], so the modern seed production of potatoes in this region, referred to as the zone of risky farming, is impossible without the improvement of existing methods of reproducing the healthy initial seed material in in vitro conditions. Analysis of recent research and publications. The effectiveness of the biotechnological method depends on a number of factors: the intensity of the illumination, the temperature regime, the duration of the photoperiod, and others [5][6][7][8][9].The basis of plant tissue cell culturing in in vitro condition is the composition of the nutrient medium, which includes micro-and macro salts, vitamins, stimulants, etc. [6, 8, 9-13]. Studies [14] show that even the plants parts which are spliting during the cutting are distinguished by the influence on the induction of microtuber formation and on the resistance of the plants against the viral infection [15]. It should be noted that various cultivars have their reaction to the same conditions of cultivation in in vitro conditions [16][17][18][19][20]. In addition, the complex influence of the differend tiers of steems, potato cultivars of different ripening groups and the composition of the nutrient medium is not well-studied, which means that their complex research acquires an urgency in solving the problem of optimizing the process of tuber formation in in vitro culture.The purpose of research. To determine the most optimal regimes of tuber formation of potato cultivars of different ripening groups depending of the parts of plants in vitro and the composition of the nutrient medium.Materials and methods of research. The studies were carried out under micr...

The purpose. To determine the optimum technological methods influencing heightening intensity of tuber-formation of potato of early ripening variety Kobza in crop of stolons in vitro. Methods. Complex use of laboratory, mathematical-statistical, calculation-comparative methods and system analysis. Results. Experimental data are resulted on influence of density of saccharose and aucsins in nutrient medium on induction of tuber-formation at reproduction of potato in crop of stolons in vitro. Conclusions. The maximum productivity and reward payment of holdings at determination of optimum elements of technique of growing of microtubers of early ripening variety of potato Kobza in crop of stolons in vitro is generated at adding in nutrient medium of saccharose in dose of 80 g/l and kinetin in dose of 0,5 mg/l. Mass of average microtuber is 53,2 mg, amount of stolons which have organized microtubers-87% at the cost price of microtuber 2,49 hrn and profitableness of production 141%.